EVALUATION OF THE MARCONI PERSONAL ROLE RADIO

Transcription

1 DRDC-Toronto CR EVALUATION OF THE MARCONI PERSONAL ROLE RADIO by: David W. Tack and Edward T. Nakaza Humansystems Incorporated 111 Farquhar St., 2 nd floor Guelph, ON N1H 3N4 Project Director: David W. Tack (519) PWGSC Contract No. W /001/TOR Call-Up HSI SIREQ Item #88 On behalf of DEPARTMENT OF NATIONAL DEFENCE as represented by Defence Research and Development Canada - Toronto 1133 Sheppard Avenue West Toronto, Ontario, Canada M3M 3B9 DRDC Toronto Scientific Authority LCol Linda Bossi (416) May 2005 This document contains information that may not be passed or shared, even in confidence, with foreign military, research and development representatives or civilian contractors of any nationality without the expressed prior permission of the Exploitation Manager of SIREQ TD. The scientific or technical validity of this Contract Report is entirely the responsibility of the contractor and the contents do not necessarily have the approval or endorsement of Defence R&D Canada Her Majesty the Queen as represented by the Minister of National Defence, 2005 Sa Majesté la Reine, représentée par le ministre de la Défense nationale, 2005

2 Abstract This experiment investigated the differences between the current in-service Tactical Command Control and Communications System (TCCCS) radio condition versus the Personal Role Radio (PRR) in situation awareness, mental workload, teamwork, coordination, communication effectiveness and mission performance. It also assessed the tactical feasibility and usability issues specific to the PRR product and whether the PRR should be acquisitioned for the Canadian Armed Forces. The findings from our SIREQ 1 experiments have concluded that a small unit radio enhanced successful information transfer in a timely manner, better coordinated attacks within Section and within Platoon, increased flow of communication, increased mission tempo, improved ammunition consumption as a result of more effective fire control, improved cueing of indirect fire support resulting from the faster dissemination of information, and increased individual and collective situational awareness. In conclusion, lessons learned (LL) and tactics, techniques and procedures (TTP s) based on findings from past and present Fort Benning Experimentation Series (FBES), and drawn extensively from the United States Marine Corps, Marine Corps Warfighting Laboratory (MCWL), UK Government, and non-military publications are discussed. 1 SIREQ TD stands for Soldier Information REQuirements Technology Demonstration project. This is a 4- year research effort, led by DRDC Toronto, to scientifically validate the information and display capabilities that will dramatically improve the situation awareness, target acquisition and command execution performance of the Canadian dismounted soldier of the future (Tack and Nakaza, 2002). Humansystems Incorporated PRR Evaluation Page i

3 Résumé Dans le cadre de cette expérience, on a étudié les différences entre le poste radio Système tactique de commandement, de contrôle et de communication (STCCC) utilisé actuellement en service et le poste radio personnel (PRP) dans les cas suivants : connaissance de la situation, charge de travail mental, travail d équipe, coordination, efficacité de la communication et le rendement pendant la mission. On a également évalué les questions de faisabilité tactique et d utilisation propres au produit PRP et on a déterminé s il faut faire l acquisition du PRP pour les Forces canadiennes. Les résultats des expériences SIREQ 2 ont révélé qu un petit poste radio permettait d accélérer le transfert de l information, de mieux coordonner les attaques au sein de la Section et du peloton, d accroître la transmission des messages et la cadence opérationnelle, d améliorer la consommation de munitions par suite d une conduite de tir plus efficace ainsi que la signalisation de l appui-feu indirect grâce à la diffusion plus rapide de l information et d accroître la connaissance individuelle et collective de la situation. En somme, on a analysé les leçons retenues (LR) ainsi que les tactiques, techniques et procédures (TTP) basées sur les résultats de la série d expérimentations antérieures et actuelles menées à Fort Benning et tirées de documents non militaires et de documents publiés par le United States Marine Corps, le Marine Corps Warfighting Laboratory (MCWL) et le gouvernement du R.-U. 2 Dirigé par RDDC Toronto, SIREQ TD, ou Projet de démonstration de technologie des besoins des soldats en matière d information, est un projet d une durée de quatre ans. Il vise à valider scientifiquement les capacités en matière d informations et de présentations qui permettront d améliorer considérablement la connaissance de la situation, l acquisition de cibles et le rendement du futur soldat débarqué canadien en ce qui concerne l exécution des commandes. (Tack et Nakaza, 2002). Humansystems Incorporated PRR Evaluation Page ii

4 Executive Summary The SIREQ 3 cognitive task analyses identified the abilities to transfer information and to communicate between members in dismounted infantry Sections as critical requirements for mission success. In the case of a typical execution phase of any mission, soldiers currently whisper or use hand signals, passed from person to person, during stealthy actions or use yelled voices during engagement actions. Both methods have their shortcomings. To overcome these current deficiencies in intra and inter-section communications, most soldier modernization programmes have adopted an intra and inter-section radio as part of their hardware ensemble (Tack and Adams, 2002). Therefore this current experiment investigated the differences between the current in-service Tactical Command Control and Communications System (TCCCS) radio condition versus the Personal Role Radio (PRR) in situation awareness, mental workload, teamwork, coordination, communication effectiveness and mission performance. It also assessed the tactical feasibility and usability issues specific to the PRR product and whether the PRR should be acquisitioned for the Canadian Armed Forces. A troop trial and a series of two PRR experiments were completed over the course of 2002 and 2003 at Fort Benning, Georgia, U.S.A. with eighty-nine Canadian Forces (CF) infantry soldiers. The most recent experiment built upon previous findings and required three Sections and a Weapons Detachment (Det.) to maneuver independently through wooded terrain to an objective rendezvous. The Platoon then advanced to engage a Section of enemy force soldiers occupying a defensive position in the MOUT village. Forty-seven regular force infantry soldiers undertook force-on-force tactical assault missions through wooded terrain to the urban environment. Subjective evaluations from questionnaire data included information transfer, within section abilities, within platoon abilities, overall acceptance, acceptance of radio statements, importance of radios, important radio features, and the acceptability of PRR equipment features: radio, headset, remote PTT. Participants ranked all radio conditions upon completion of the experiment. A focus group discussion with all participants following the testing allowed key issues to be reviewed. The findings from our SIREQ experiments have concluded that a small unit radio enhanced successful information transfer in a timely manner, better coordinated attacks within Section and within Platoon, increased flow of communication, increased mission tempo, improved ammunition consumption as a result of more effective fire control, improved cueing of indirect fire support resulting from the faster dissemination of information, and increased individual and collective situational awareness. When compared to the current in-service TCCCS only condition, a highly statistically significant effect was observed where soldiers were unanimously in favour of the PRR. While the overall acceptance of the PRR condition was significantly 3 SIREQ TD stands for Soldier Information REQuirements Technology Demonstration project. This is a 4- year research effort, led by DRDC Toronto, to scientifically validate the information and display capabilities that will dramatically improve the situation awareness, target acquisition and command execution performance of the Canadian dismounted soldier of the future (Tack and Nakaza, 2002). Humansystems Incorporated PRR Evaluation Page iii

5 higher than for the current in-service TCCCS only condition, a number of specific design shortcomings have been identified with the PRR. Chief among these concerns were the transmission cut-outs with the PTT, headset cord length, and the need for a right ear headset for left eye shooters. Soldiers also felt the need for a PRR standard operating procedure (SOP) in order to ensure effective communications can be maintained. In conclusion, lessons learned (LL) and tactics, techniques and procedures (TTP s) based on findings from past and present Fort Benning Experimentation Series (FBES), and drawn extensively from the United States Marine Corps, Marine Corps Warfighting Laboratory (MCWL), UK Government, and non-military publications are discussed. The listed LL and TTP s are particulars, which have been discovered during laboratory testing and field experiments and may be combined with the current CF doctrine, which will provide best practices for this new item of soldier equipment. Humansystems Incorporated PRR Evaluation Page iv

6 Sommaire Les analyses cognitives des tâches associées au SIREQ 4 ont révélé que la capacité de transférer des informations et de communiquer avec d autres militaires dans des sections d infanterie débarquées était essentielle au succès d une mission. Lors d une phase d exécution traditionnelle d une mission donnée, les soldats communiquent actuellement à voix basse ou par des signes de la main, durant les missions discrètes, ou en criant, durant les engagements. Les deux méthodes comportent des lacunes. Afin de corriger les lacunes actuelles liées à la communication intrasection ou intersection, les responsables de la plupart des programmes de modernisation du soldat ont adopté un poste radio intrasection et intersection et l ont ajouté à leur ensemble de matériel (Tack et Adams, 2002). Par conséquent, on a étudié dans le cadre de cette expérience les différences entre le poste radio Système tactique de commandement, de contrôle et de communication (STCCC) utilisé actuellement en service et le poste radio personnel (PRP) dans les cas suivants : connaissance de la situation, charge de travail mental, travail d équipe, coordination, efficacité de la communication et le rendement pendant la mission. On a également évalué les questions de faisabilité tactique et d utilisation propres au produit PRP et on a déterminé s il faut faire l acquisition du PRP pour les Forces canadiennes. Un essai en unité et une série de deux expériences mettant en jeu le PRP ont été effectués en 2002 et 2003, à Fort Benning, en Géorgie, aux É.-U. Quatre-vingt-neuf soldats d infanterie des Forces canadiennes (FC) y ont participé. Dans le cadre de la plus récente expérience qui s est fondée sur des résultats obtenus antérieurement, trois sections et un détachement d armes devaient traverser indépendamment un terrain forestier pour se rendre à un point de rendez-vous à l objectif. Le peloton s est avancé par la suite pour engager le combat contre une section de forces ennemies en position de défense dans le village où se déroule l Op ZB. Quarante-sept soldats d infanterie de la Force régulière ont mené des missions tactiques d assaut de force contre force avançant à travers un terrain pour atteindre le milieu urbain. Des évaluations subjectives réalisées à partir de données de questionnaire portaient sur le transfert d informations, que la section et le peloton ont eu la capacité d effectuer, l acceptation générale, l acceptation des énoncés communiqués par radio, l importance des radios, les éléments importants du poste radio et l acceptabilité des composantes du PRP : radio, casque d écoute, PTT à distance. Les participants ont évalué tous les éléments du poste radio à la fin de l expérience. Après l essai, un groupe de discussion a rencontré tous les participants pour analyser des points clés. Les résultats des expériences SIREQ ont révélé qu un petit poste radio permettait d accélérer le transfert de l information, de mieux coordonner les attaques au sein de la Section et du peloton, 4 Dirigé par RDDC Toronto, SIREQ TD, ou Projet de démonstration de technologie des besoins des soldats en matière d information, est un projet d une durée de quatre ans. Il vise à valider scientifiquement les capacités en matière d informations et de présentations qui permettront d améliorer considérablement la connaissance de la situation, l acquisition de cibles et le rendement du futur soldat débarqué canadien en ce qui concerne l exécution des commandes. (Tack et Nakaza, 2002). Humansystems Incorporated PRR Evaluation Page v

7 d accroître la transmission des messages et la cadence opérationnelle, d améliorer la consommation de munitions par suite d une conduite de tir plus efficace ainsi que la signalisation de l appui-feu indirect grâce à la diffusion plus rapide de l information et d accroître la connaissance individuelle et collective de la situation. Lorsqu on a comparé ce poste radio au STCCC en usage actuellement en service, on a remarqué que tous les soldats s étaient unanimement prononcés en faveur du PRP, ce qui est très significatif. Certes le STCCC, qui est en service actuellement, est beaucoup moins populaire que le PRP, si l on juge par l acceptation générale de celui-ci, mais certains défauts de conception ont été décelés chez le PRP, dont les plus importants étaient les coupures de la transmission, la longueur du cordon du casque d écoute et le manque d un casque d écoute qui se porte dans l oreille droite pour les tireurs qui visent avec l œil gauche. Les soldats ont également noté qu il était nécessaire d élaborer des instructions permanentes d opération (IPO) pour le PRP afin de maintenir l efficacité des communications. En somme, on a analysé les leçons retenues (LR) ainsi que les tactiques, techniques et procédures (TTP) basées sur les résultats de la série d expérimentations antérieures et actuelles menées à Fort Benning et tirées de documents non militaires et de documents publiés par le United States Marine Corps, le Marine Corps Warfighting Laboratory (MCWL) et le gouvernement du R.-U. Les LR et les TTP énumérées sont précises puisqu elles sont le fruit d essais en laboratoire et d expériences sur le terrain. Elles peuvent être intégrées à la doctrine actuelle des FC, ce qui fournira des pratiques exemplaires pour ce nouvel article de l équipement du soldat. Humansystems Incorporated PRR Evaluation Page vi

8 Table of Contents ABSTRACT...I RÉSUMÉ... II EXECUTIVE SUMMARY...III SOMMAIRE... V TABLE OF CONTENTS... VII LIST OF TABLES...VIII LIST OF FIGURES...IX 1 BACKGROUND AIMS METHOD OVERVIEW PARTICIPANTS QUESTIONNAIRE RATING SCALE MATERIALS Marconi Radio PROCEDURE Approach LIMITATIONS RESULTS SUBJECTIVE PERFORMANCE MEASURES Exit Questionnaire for Information Transfer Exit Questionnaire for Within Section Use of Information Exit Questionnaire for Within Platoon Use of Information Overall Acceptance Statements of Importance Importance of a Radio for Mission Phase Importance of a Radio for Mission Features Acceptability of PRR Equipment Features LESSONS LEARNED Setup Operation Security Additional Constraints and Recommendations Method of Destruction Warnings!!!: DISCUSSION REFERENCES APPENDIX A: EXIT QUESTIONNAIRE...A-1 Humansystems Incorporated PRR Evaluation Page vii

9 List of Tables TABLE 1: STATEMENTS OF IMPORTANCE TABLE 2: MISSION PHASES TABLE 3: MISSION FEATURES TABLE 4: PRR RADIO FEATURES TABLE 5: PRR HEADSET FEATURES TABLE 6: PRR REMOTE PUSH-TO-TALK FEATURES Humansystems Incorporated PRR Evaluation Page viii

10 List of Figures FIGURE 1: CF SOLDIER USING MARCONI PRR... 2 FIGURE 2: MCKENNA MOUT SITE... 4 FIGURE 3: STANDARD RATING SCALE... 5 FIGURE 4: MARCONI PRR RADIO AND ANCILLARIES... 7 FIGURE 5: OVERALL INFORMATION TRANSFER (LEADERS) FIGURE 6: OVERALL INFORMATION TRANSFER (NON LEADERS) FIGURE 7: OVERALL WITHIN SECTION (LEADERS) FIGURE 8: OVERALL WITHIN SECTION (NON LEADERS) FIGURE 9: OVERALL WITHIN PLATOON (LEADERS) FIGURE 10: OVERALL WITHIN PLATOON (NON LEADERS) FIGURE 11: OVERALL ACCEPTANCE (LEADERS) FIGURE 12: OVERALL ACCEPTANCE (NON LEADERS) FIGURE 13: OVERALL ACCEPTANCE (LEADERS VS. NON LEADERS) FIGURE 14: STATEMENT OF IMPORTANCE FIGURE 15: IMPORTANCE OF A RADIO FOR MISSION PHASE FIGURE 16: IMPORTANCE OF A RADIO FOR MISSION FEATURES FIGURE 17: PRR RADIO FEATURE ACCEPTABILITY FIGURE 18: PRR HEADSET FEATURE ACCEPTABILITY FIGURE 19: PRR REMOTE PTT FEATURE ACCEPTABILITY Humansystems Incorporated PRR Evaluation Page ix

11 1 Background Dominance in effective communications has been a fundamental factor in warfare success but the prolific advances in information and computing dissemination technology in the past century, will provide the infantry soldier with resources that were beyond everyone s imagination only a decade ago. (global-defence.com, 2003) The SIREQ cognitive task analyses identified the abilities to transfer information and to communicate between members in dismounted infantry Sections as critical requirements for mission success. In the case of a typical execution phase of any mission, soldiers currently whisper or use hand signals, passed from person to person, during stealthy actions or use yelled voices during engagement actions. Both methods have their shortcomings: hand signals require a line of sight between the sender and receiver and good visibility, and raised voices indicate the speaker s location to the enemy, reveal your intent to the English speaking enemy, and risk intelligibility problems or the message being unheard in noisy battle conditions. To overcome these current deficiencies in intra and inter-section communications, most soldier modernization programmes have adopted an intra and inter-section radio as part of their hardware ensemble (Tack and Adams, 2002). Accepting the deficiencies in our current methods of intra and inter-section communication, the choice of a radio still raises a number of issues and opportunities for investigation. While the provision of a radio would seem intuitively attractive for addressing the transfer of information within and between the Section, SIREQ needs to determine which performance parameters are enhanced by the use of a radio and how these enhancements affect measures of mission outcome. For example, does the provision of a radio enhance individual and/or collective situation awareness, reduce individual mental workload, and/or improve team coordination and execution? If some or all of these enhancements are realized by the addition of a radio, are these enhancements sufficiently large enough to increase the likelihood and degree of mission success (e.g. fewer errors in execution, faster mission execution, fewer friendly casualties, more enemy casualties, fewer resources expended)? It is likely that providing a radio will enhance some elements of individual and/or collective performance and that some of these enhancements will improve some aspects of mission outcome (Tack and Adams, 2002). To overcome these current deficiencies, this experiment investigated the above limitations and factors using the Personal Role Radio (PRR) during close-in warfare, by empirically comparing the subjective performance of soldiers at the Fort Benning McKenna MOUT 5 site over the course of Fort Benning Experimentation Series #5 (FBES#5). The H4855 PRR, developed by Marconi Kominikasyon A.Ş, provides short-range communication for the dismounted infantry soldier. The PRR includes a ruggedized, wireless LAN radio (2.4 GHz), wireless push-to-talk (PTT), integrated headset with boom microphone, ensures that the system has a low probability of interception (LPI) and low probability of 5 MOUT stands for Military Operations in Urban Terrain. The current Canadian Forces (CFs) equivalent terminology is FIBUA (Fighting in Built-Up Areas) although there is a move to rename to Urban Operations. Humansystems PRR Evaluation Page 1

12 detection (LPD), and gives the soldier a dedicated system to meet the full range of front line communication requirements. Reference Figure 1. PRR Headset PRR Radio Figure 1: CF Soldier Using Marconi PRR Both the Director Land Requirements 5 (DLR 5) and SIREQ were interested in investigating the issues and opportunities afforded by such a product at both the Section and Platoon levels. Humansystems PRR Evaluation Page 2

13 2 Aims This experiment evaluated the suitability of the PRR for small unit missions according to the following aims: Investigate the differences in situation awareness, mental workload, and mission performance between radio conditions. Compare teamwork, coordination, and communication effectiveness between radio conditions. Assess the tactical feasibility and usability issues specific to the PRR product. Humansystems PRR Evaluation Page 3

14 3 Method 3.1 Overview The following description provides a general overview of the trial method. Further details are provided in subsequent sections. This most recent experiment built upon previous findings and investigated the suitability of the PRR for small unit missions by empirically comparing the subjective performance of soldiers during the course of platoon missions. An eight-day field trial over the period of 7-17 March 2003, was undertaken at Ft. Benning, Georgia. Forty-seven regular force infantry soldiers were required to undertake force-on-force tactical assault missions through wooded terrain to assault and secure a small village. The assaulting force comprised a Company HQ, two Platoon HQs, three dismounted infantry Sections, and a Weapons Detachment (Det.) to assault one defending Section in the McKenna MOUT. Reference Figure 2. Figure 2: McKenna MOUT Site The analyses reported in this report are based on the results from this most recent trial, however, the accompanying lessons learned (LL) and the tactics techniques and procedures (TTPs) documented in this report were based on findings from this trial as well as the following previous trials. Troop Trial: A six-day field troop trial was undertaken at Fort Benning, Georgia over the period 3-15 November, Twenty-six regular force infantry soldiers were required to participate in simulated field missions, during daytime section and platoon attacks. Field Trial: A four-day field trial was also undertaken at Fort Benning, Georgia over the period of 4-8 November Two groups of eight regular force infantry soldiers were required to participate in MOUT clearing tactics as members of an assault group during day and nighttime operations. Humansystems PRR Evaluation Page 4

15 Soldiers were required to complete missions in each of the following radio assignment conditions. 1. TCCCS (Tactical Command, Control and Communications Systems) Only: This condition comprised the current in-service assignment of TCCCS radios to the Section Comd, Pl Comd, and Coy Comd. No other soldiers were equipped with radios. 2. PRR All: All members of the assaulting force were provided with PRR s. During the PRR All radio condition, each Section and Weapons Det. Commander was able to speak to his Section on an all informed net. Each Section and Weapons Det. Commander also had the ability to switch to any other Section net and had the ability to contact the Platoon Leader. Commanders at all levels had the two-pressel combat net radio (CNR) switch allowing them to operate the TCCCS (521 and 522) on the PRR handset. During each experimentation session, the presentation of PRR conditions was balanced to minimize order effects amongst participants. Questionnaires, focus group comments, and Human Factor (HF) observer assessment data was collected and analyzed. Statistical differences were determined using a balanced, repeated-measures analysis of variance for the exit questionnaire results. Differences were identified at p 0.05 and n=13 for all the Leader conditions (n=8 for the Within Section data), and n=17 for all the non Leader conditions and n=30 for the combined data. Duncan s post-hoc analyses were conducted on significant exit questionnaire results. 3.2 Participants Forty-seven regular force infantry soldiers were recruited from the Princess Patricia Canadian Light Infantry (3PPCLI), to participate in this study. The mean age of the participants was 25.8 years (SD=5.5, max=38, min=18). The mean service in the regular forces was 5.1 years (SD=0.7, max=17, min=1). The group consisted of one Major (2.1%), two Lieutenants (4.3%), one Warrant Officer (2.1%), four Sergeants (8.5%), five Master Corporals (10.6%), nine Corporals (19.1%), and twenty-five Privates (53.2%). 3.3 Questionnaire Rating Scale Participants rated Information Transfer, Within Section and Within Platoon acceptability using the seven-point scale shown in Figure 3. Figure 3: Standard Rating Scale Humansystems PRR Evaluation Page 5

16 3.4 Materials Marconi Radio Main Features The PRR uses advanced wireless LAN technology incorporating spread spectrum techniques at 2.4 GHz, to ensure that the system has a low probability of interception and detection, and minimizes interference between co-located PRR s. Two variants of the Push-to-Talk (PTT) switch assembly are provided for single or dual radio operation. The headset is developed from in-service designs and is both rugged and flexible being compatible with all standard military headgear. A wireless hands-free PTT is also incorporated into the system. Operating at 435 MHz, the uniquely encoded PTT can operate the PRR PTT from a few meters, giving users the freedom to concentrate on primary tasks. Reference Figure 4. Other Features: Up to 500 m Range Compatibility with all military clothing and protective head gear Simple user interface 256 Channel capability (16 directly available to the user) Easily mounted on the user small and unobtrusive Operates in a wide range of military scenarios Operates independently of any infrastructures Operates from 2 standard AA size batteries Humansystems PRR Evaluation Page 6

17 Figure 4: Marconi PRR Radio and Ancillaries The Radio The radio is simple to operate, small and lightweight (0.5 kg or 1.1 lbs with batteries and ancillaries) and does not require any other communications infrastructure. It uses two standard AA size battery cells and can operate with most primary and secondary battery technologies including alkaline and lithium. The radio requires no support in the field beyond the replacement or recharging of battery cells and can be rapidly deployed to become part of the soldier s personal equipment. The radio transmissions utilize a proprietary form of Direct Sequence Spread Spectrum, which, to an eavesdropper, will appear like noise. The radio thus has good resistance against interfering signals and provides a LPI and LPD. The Ancillaries The earpiece and microphone are mounted on common webbing which has a headband plus an over the head strap to ensure that the microphone and headset remain in position after adjustment by the wearer. In particular, it will not slip during exertion or body movement. The microphone has been shaped in order to ensure that it does not impede the peripheral vision of the wearer, especially when using a standard Army infantry weapon. In addition, the microphone will be worn outside an NBC mask, in conjunction with an extension tube, to provide clear and intelligible voice. This offers significant improvements over standard fitted equipment. Humansystems PRR Evaluation Page 7

18 Technical Characteristics Operating Frequency Transmit Power Modulation 2, MHz 256 Channels available 50 Mw Direct Sequence Spread Spectrum Voice Coding CVSD Data Protocol Modified IEEE Battery 2 AA primary cells provide typically 24 hour use (1:7:16 Tx/Rx/S BY Ratio) Range 500 meters (Rural Terrain) transmission through up to three floors (Urban Terrain) Microphone Electret Noise Canceling Respirator NBC Compatible Ear Piece Custom Molded design Compatibility VHF Combat Radio UHF Combat Radio HF Combat Radio Hands Free Operation 435 MHz wireless operation 128 Bit Unique Coding Simple Code Learn Mode (Marconi.com, 2001) 3.5 Procedure Approach Participants were given an orientation briefing verbally, and in writing, on the overall study, its objectives, test activities, mission structure, and the protocol for the experiment. This experiment offered minimal risk to the participant s health and wellbeing. There were anticipated risks with this experiment, which were normally associated with the activities conducted during field exercises including: trips, falls or sprains, and exertion-related heat illness or injury. All participants were required to read and sign an ethics approved consent form. One Platoon assault was performed every afternoon for eight days. For any one mission, the Platoon assault started with each of the three Sections, the Weapons Det., and the Platoon head quarter (HQ) being deployed to separate initiation points about 500 m from the objective village. The initiation point locations were balanced and randomized to minimize order effects amongst participants. Each Section and Weapons Det. maneuvered independently through wooded terrain Humansystems PRR Evaluation Page 8

19 to an objective rendezvous (ORV). Following a quick reconnaissance of the MOUT, the Platoon Commander updated his plan of attack and briefed his Section Commanders. The Platoon then advanced to engage a Section of enemy soldiers occupying a defensive position in the MOUT village. The enemy force soldiers were not subjects in the PRR experiment. Radios were used to coordinate movements, actions, and fire at both the Platoon and Section levels. HF measures included assessments of mission performance, situation awareness, workload, communication measures and teamwork factors, as well as the subjective utility and usability assessments of the PRR s. Data collection included questionnaires, focus group comments, and HF observer assessments. 3.6 Limitations This study had several limitations. Although the experimenters tried to balance and randomize the initiation points and objective buildings, the soldiers had become very familiar with the wooded terrain and MOUT village after experience with several attacks. This may have inclined the soldiers to a better cognitive map of the environment and thereby requiring less PRR use to acquire sufficient situational awareness. Due to the nature of the PRR, the size of the participant sample, and the difficulty in capturing communication data with this system, the results reported in this experiment were limited to subjective questionnaire and focus group data collected in a controlled field environment. Humansystems PRR Evaluation Page 9

20 4 Results 4.1 Subjective Performance Measures Due to the mixed distribution of the radio conditions between the Leaders and non Leaders during the course of this experiment, the subjective data was divided into Leader and non Leader groupings for Information Transfer, Within Section, Within Platoon, and Overall Acceptance, and analyzed. To determine the interaction effects between the radio conditions, planned comparisons were performed investigating the conditions on specific Exit Questionnaire parameters. Statistical analyses consisted of repeated measures ANOVA between conditions for the Exit Questionnaire data and Duncan s post-hoc analyses were conducted on significant results for further interrogation. In addition, the combined results from both the Leaders and non Leaders acceptance of radio statements, importance of radios, important radio features, and acceptability of PRR equipment features(radio, Headset, Remote PTT) were examined. Significant differences were identified at p 0.05 and n=13 for all the Leader conditions (n=8 for the Within Section data), and n=17 for all the non Leader conditions and n=30 for the combined data. Unless otherwise noted on the following graphs, a geometric shape denotes the subjective means, the box denotes ± 1 standard error, and the error bars denote ± 1 standard deviation Exit Questionnaire for Information Transfer Infantry Leaders and non Leaders rated the acceptability of the Information Transfer abilities of the experimentation conditions with the statements, Amount of Information that can be Passed, Time Required to Pass Information, Timeliness for Initiating Comms, Ease of Passing Information, Ease of Requesting Information, Ease of Receiving Information, Ease of Getting Acknowledgement of Information Received, Ease of Getting Acknowledgement of Information Understood, Accuracy of Information Passed, and Message Detail Possible. The scaled ratings of the Leaders and non-leaders (1 to 7) were tabulated, and means computed for each condition separately Overall Information Transfer (Leaders) When comparing the Leader s response to all ten information transfer variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 12)=21.0, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all ten information transfer questions versus the TCCCS only radio condition. Reference Figure 5. The Leader s mean acceptability ratings demonstrate that the PRR s were better accepted than the current in-service option for the overall transfer of information. Humansystems PRR Evaluation Page 10

21 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only Radio Condition PRR Amnt Info Pass Tme Info Pass Tme Init Comm Ease Pass Info Ease Rqst Info Ease Rcve Info Ease Ackn Info Rcve Ease Ackn Undstd Accuracy Info Mssge Detail Figure 5: Overall Information Transfer (Leaders) Amount of Information that can be Passed (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the amount of information that can be passed, F(1, 12)=39.41, p<.001, with the PRR being more acceptable in the amount of information passed than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Time Required to Pass Information (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the time required to pass information, F(1, 12)=11.64, p=.005, with the acceptability of the PRR higher than compared to the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable. Humansystems PRR Evaluation Page 11

22 Timeliness for Initiating Comms (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the timeliness for initiating comms, F(1, 12)=14.34, p=.003, with the PRR being more acceptable in the timeliness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Passing Information (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of passing information, F(1, 12)=9.72, p=.01, with the PRR being more acceptable in the passing of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Requesting Information (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of requesting information, F(1, 12)=9.04, p=.01, with the PRR being more acceptable in the requesting of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Receiving Information (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of receiving information, F(1, 12)=15.70, p=.002, with the PRR being more acceptable in the receiving of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Getting Acknowledgement of Information Received (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of getting acknowledgement of information received, F(1, 12)=14.63, p=.002, with the PRR being more acceptable in getting acknowledgement of information received than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Getting Acknowledgement of Information Understood (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of getting acknowledgement of information understood, F(1, 12)=7.80, p<.02, with the PRR being more acceptable in getting acknowledgement of information understood than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Humansystems PRR Evaluation Page 12

23 Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Accuracy of Information Passed (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the accuracy of information passed, F(1, 12)=8.35, p<.02, with the PRR being more acceptable in passing accurate information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Message Detail Possible (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the message detail possible, F(1, 12)=11.93, p<.005, with the PRR being more acceptable in terms of possible detail than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Overall Information Transfer (Non Leaders) When comparing the non Leader s response to all ten information transfer variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 16)=39.12, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all ten information transfer questions versus the TCCCS only radio condition. Reference Figure 6. Similar to the Leader s mean acceptability ratings, the non Leader s mean acceptability ratings demonstrate that the PRR s were better accepted than the current in-service option for the overall transfer of information. Humansystems PRR Evaluation Page 13

24 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only Radio Condition PRR Amnt Info Pass Tme Info Pass Tme Init Comm Ease Pass Info Ease Rqst Info Ease Rcve Info Ease Ackn Info Rcve Ease Ackn Undstd Accuracy Info Mssge Detail Figure 6: Overall Information Transfer (Non Leaders) Amount of Information that can be Passed (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the amount of information that can be passed, F(1, 16)=34.00, p<.001, with the PRR being more acceptable in the amount of information passed than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Time Required to Pass Information (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the time required to pass information, F(1, 16)=30.16, p<.001, with the acceptability of the PRR higher than compared to the TCCCS. The mean acceptability rating for the TCCCS radio was less than Borderline, while the PRR was rated between Reasonably Acceptable and Completely Acceptable. Humansystems PRR Evaluation Page 14

25 Timeliness for Initiating Comms (Non Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the timeliness for initiating comms, F(1, 16)=12.36, p<.002, with the PRR being more acceptable in the timeliness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Passing Information (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of passing information, F(1, 16)=26.24, p<.001, with the PRR being more acceptable in the passing of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Ease of Requesting Information (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of requesting information, F(1, 16)=29.33, p<.001, with the PRR being more acceptable in the requesting of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Ease of Receiving Information (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of receiving information, F(1, 16)=29.33, p<.001, with the PRR being more acceptable in the receiving of information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Ease of Getting Acknowledgement of Information Received (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of getting acknowledgement of information received, F(1, 16)=21.84, p<.001, with the PRR being more acceptable in getting acknowledgement of information received than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Ease of Getting Acknowledgement of Information Understood (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of getting acknowledgement of information understood, F(1, 16)=25.91, p<.001, with the PRR being more acceptable in getting acknowledgement of information understood than with the TCCCS. The mean acceptability rating for the TCCCS radio was Humansystems PRR Evaluation Page 15

26 between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Accuracy of Information Passed (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the accuracy of information passed, F(1, 16)=50.26, p<.001, with the PRR being more acceptable in passing accurate information than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Message Detail Possible (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the message detail possible, F(1, 16)=25.52, p<.001, with the PRR being more acceptable compared to the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Exit Questionnaire for Within Section Use of Information Infantry Leaders and non Leaders rated the acceptability of the Within Section use of information with the statements, Coordination of Movement, Coordination of Fire, Coordination of Action, Issuing/Receiving Orders, Designating Targets, Ease of Distributing Message Within Section, Awareness of Location of Your Section Members, Awareness of Casualties Among Your Section Members, and Awareness of Ammunition Usage of Your Section. The scaled ratings of the Leaders and non-leaders (1 to 7) were tabulated, and means computed for each condition separately Overall Within Section Use of Information (Leaders) When comparing the Leader s response to all nine Within Section variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 7)=37.36, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all Within Section questions versus the TCCCS only radio condition. Reference Figure 7. The Leader s mean acceptability ratings demonstrate that overall the PRR s were better accepted than the current in-service option for the communication of information within Sections. Humansystems PRR Evaluation Page 16

27 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only PRR Coord mvt Coord fire Coord action Issue/rcve order Design trgts Ease distr mssg Aware loctn Sectn Aware casualties Aware ammo use Radio Condition Figure 7: Overall Within Section (Leaders) Coordination of Movement (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of movement, F(1, 7)=11.67, p=.01, with the PRR being more acceptable in coordinating than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated Reasonably Acceptable Coordination of Fire (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of fire, F(1, 7)=8.79, p=.02, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable. Humansystems PRR Evaluation Page 17

28 Coordination of Action (Leaders) There was no significant difference found between the two radio conditions in terms of the coordination of action within the section, F(1, 7)=3.32, p=.11. The participants mean acceptability rating for both the TCCCS radio and the PRR was between Barely Acceptable and Reasonably Acceptable Issuing/Receiving Orders (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of issuing/receiving orders, F(1, 7)=15.91, p=.005, with the PRR being more acceptable in the issuing/receiving orders than with the TCCCS. The mean acceptability rating for the TCCCS radio was less than Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Designating Targets (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of designating targets, F(1, 7)=14.00, p=.007, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was less than Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Ease of Distributing Message Within Section (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of distributing messages, F(1, 7)=58.33, p<.001, with the PRR being more acceptable in the distribution of messages than with the TCCCS. The mean acceptability rating for the TCCCS radio was Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable Awareness of Location of Your Section Members (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of location of Section members, F(1, 7)=24.65, p<.002, with the PRR being more acceptable in location awareness of Section members than with the TCCCS. The mean acceptability rating for the TCCCS radio was Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Awareness of Casualties Among Your Section Members (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of casualties among Section members, F(1, 7)=31.50, p<.001, with the PRR being more acceptable in casualty awareness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable. Humansystems PRR Evaluation Page 18

29 Awareness of Ammunition Usage of Your Section (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of Section ammunition usage, F(1, 7)=15.91, p=.005, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Overall Within Section Use of Information (Non Leaders) When comparing the non Leader s response to all nine Within Section variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 16)=27.50, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all Within Section questions versus the TCCCS only radio condition. Reference Figure 8. Similar to the Leader s mean acceptability ratings, the non Leader s mean acceptability ratings demonstrate that the PRR s were better accepted than the current in-service option for the communication of information within Sections. Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only Radio Condition PRR Coord mvt Coord fire Coord action Issue/rcve order Design trgts Ease distr mssg Aware loctn Sectn Aware casualties Aware ammo use Figure 8: Overall Within Section (Non Leaders) Humansystems PRR Evaluation Page 19

30 Coordination of Movement (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of movement, F(1, 16)=29.07, p<.001, with the PRR being more acceptable in coordinating than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was greater than Reasonably Acceptable Coordination of Fire (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of fire, F(1, 16)=22.75, p<.001, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was less than Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Coordination of Action (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of action within the section, F(1, 16)=20.47, p<.001, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Issuing/Receiving Orders (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of issuing/receiving orders, F(1, 16)=22.28, p<.001, with the PRR being more acceptable in the issuing/receiving orders than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Designating Targets (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of designating targets, F(1, 16)=16.66, p<.001, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Ease of Distributing Message Within Section (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of distributing messages, F(1, 16)=32.00, p<.001, with the PRR being more acceptable in the distribution of messages than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Reasonably Acceptable and Completely Acceptable. Humansystems PRR Evaluation Page 20

31 Awareness of Location of Your Section Members (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of location of Section members, F(1, 16)=16.82, p<.001, with the PRR being more acceptable in location awareness of Section members than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Awareness of Casualties Among Your Section Members (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of casualties among Section members, F(1, 16)=18.00, p<.001, with the PRR being more acceptable in casualty awareness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Awareness of Ammunition Usage of Your Section (Non Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of Section ammunition usage, F(1, 16)=15.62, p=.001, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Exit Questionnaire for Within Platoon Use of Information Infantry Leaders and non Leaders rated the acceptability of the Within Platoon use of information with the statements, Coordination of Platoon Movement, Coordination of Platoon Fire, Coordination of Platoon Action, Issuing/Receiving Orders, Designating Targets, Ease of Distributing Message Within Platoon, Awareness of Location of the Other Sections, Awareness of Casualties of the Other Sections, and Awareness of Ammunition Usage of the Other Sections. The scaled ratings of the Leaders and non-leaders (1 to 7) were tabulated, and means computed for each condition separately Overall Within Platoon Use of Information (Leaders) When comparing the Leader s response to all nine Within Platoon variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 12)=40.95, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all Within Platoon questions versus the TCCCS only radio condition. Reference Figure 9. Overall, the Leader s mean acceptability ratings demonstrate that the PRR s were better accepted than the current in-service option for the communication of information within the Platoon. Humansystems PRR Evaluation Page 21

32 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only Radio Condition PRR Coord Plt mvt Coord Plt fire Coord Plt action Issue/rcve order Design trgts Ease distr mssg Aware loctn Sectn Aware casualties Aware ammo use Figure 9: Overall Within Platoon (Leaders) Coordination of Platoon Movement (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of Platoon movement, F(1, 12)=29.67, p<.001, with the PRR being more acceptable in coordinating than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Coordination of Platoon Fire (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of fire, F(1, 12)=32.88, p<.001, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated Reasonably Acceptable. Humansystems PRR Evaluation Page 22

33 Coordination of Platoon Action (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of action within the Platoon, F(1, 12)=16.56, p<.002, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Issuing/Receiving Orders (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of issuing/receiving orders, F(1, 12)=10.29, p<.008, with the PRR being more acceptable in the issuing/receiving orders than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Designating Targets (Leaders) There was no significant difference found between the two radio conditions in terms of the designating of targets, F(1, 12)=2.86, p=.12. The participants mean acceptability rating for both the TCCCS radio and the PRR was between Borderline and Reasonably Acceptable Ease of Distributing Message Within Platoon (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of distributing messages, F(1, 12)=7.50, p<.02, with the PRR being more acceptable in the distribution of messages than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Awareness of Location of the Other Sections (Leaders) A significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of location of other Sections, F(1, 12)=15.70, p<.002, with the PRR being more acceptable in location awareness of other Sections than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Awareness of Casualties of the Other Sections (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of casualties among other Sections, F(1, 12)=36.75, p<.001, with the PRR being more acceptable in casualty awareness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Barely Unacceptable and Borderline, while the PRR was rated Barely Acceptable. Humansystems PRR Evaluation Page 23

34 Awareness of Ammunition Usage of the Other Sections (Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of ammunition usage of other Sections, F(1, 12)=24.24, p<.001, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Barely Unacceptable and Borderline, while the PRR was rated between Borderline and Barely Acceptable Overall Within Platoon Use of Information (Non Leaders) When comparing the non Leader s response to all nine Within Platoon variables between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 16)=41.10, p<.001. Duncan s post-hoc analyses showed that the PRR condition was rated significantly higher in all Within Platoon questions versus the TCCCS only radio condition. Reference Figure 10. Similar to the Leader s mean acceptability ratings, the non Leader s mean acceptability ratings demonstrate that the PRR s were better accepted than the current in-service option for the communication of information within the Platoon. Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only Radio Condition PRR Coord Plt mvt Coord Plt fire Coord Plt action Issue/rcve order Design trgts Ease distr mssg Aware loctn Sectn Aware casualties Aware ammo use Figure 10: Overall Within Platoon (Non Leaders) Humansystems PRR Evaluation Page 24

35 Coordination of Platoon Movement (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of Platoon movement, F(1, 16)=48.67, p<.001, with the PRR being more acceptable in coordinating than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Coordination of Platoon Fire (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of fire, F(1, 16)=41.09, p<.001, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Coordination of Platoon Action (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the coordination of action within the Platoon, F(1, 16)=33.80, p<.001, with the acceptability of the PRR higher than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Issuing/Receiving Orders (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of issuing/receiving orders, F(1, 16)=27.74, p<.001, with the PRR being more acceptable in the issuing/receiving orders than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated Reasonably Acceptable Designating Targets (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the designating of targets, F(1, 16)=23.87, p<.001, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable Ease of Distributing Message Within Platoon (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the ease of distributing messages, F(1, 16)=31.11, p<.001, with the PRR being more acceptable in the distribution of messages than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Borderline and Barely Acceptable, while the PRR was rated greater than Reasonably Acceptable. Humansystems PRR Evaluation Page 25

36 Awareness of Location of the Other Sections (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of location of other Sections, F(1, 16)=30.19, p<.001, with the PRR being more acceptable in location awareness of other Sections than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Barely Unacceptable and Borderline, while the PRR was rated greater than Reasonably Acceptable Awareness of Casualties of the Other Sections (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of casualties among other Sections, F(1, 16)=35.96, p<.001, with the PRR being more acceptable in casualty awareness than with the TCCCS. The mean acceptability rating for the TCCCS radio was between Barely Unacceptable and Borderline, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Awareness of Ammunition Usage of the Other Sections (Non Leaders) A highly significant difference was observed between the TCCCS and PRR radio conditions in terms of the awareness of ammunition usage of other Sections, F(1, 16)=28.51, p<.001, with the PRR being more acceptable than the TCCCS. The mean acceptability rating for the TCCCS radio was between Barely Unacceptable and Borderline, while the PRR was rated between Barely Acceptable and Reasonably Acceptable Overall Acceptance Infantry Leaders and non Leaders rated the overall suitability of the PRR and TCCCS only radio conditions with the statement, Overall Acceptance. The scaled ratings of the Leaders and non Leaders (1 to 7) were tabulated, and means computed for each condition separately. A factoral ANOVA was also conducted on the combined overall acceptability for the Leaders and non Leaders Overall Acceptance Between Radio Conditions (Leaders) When comparing the Leader s response to the Overall Acceptance between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 12)=29.67, p<.001. Overall, the Leader s mean acceptability rating of the PRR s (between Barely Acceptable and Reasonably Acceptable ) demonstrate that the PRR s were better accepted than the current in-service option which was rated between Borderline and Barely Acceptable. Reference Figure 11. Humansystems PRR Evaluation Page 26

37 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only PRR Radio Condition Mean ±SE ±SD Figure 11: Overall Acceptance (Leaders) Overall Acceptance Between Radio Conditions (Non Leaders) When comparing the non Leader s response to the Overall Acceptance between the two radio conditions (TCCCS only vs. PRR), a highly statistically significant effect was observed, F(1, 16)=46.23, p<.001. Overall, the non Leader s mean acceptability rating of the PRR s (between Reasonably Acceptable and Completely Acceptable ) demonstrate that the PRR s were better accepted than the current in-service option which was rated between Borderline and Barely Acceptable. Reference Figure 12. Humansystems PRR Evaluation Page 27

38 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only PRR Radio Condition Mean ±SE ±SD Figure 12: Overall Acceptance (Non Leaders) Overall Acceptance (Leaders vs. Non Leaders) When comparing the Overall Acceptance ratings between the Leaders and non Leaders, no significant result was observed, F(1, 56)=.02, p=.89. When combining the results for the Leader s and non Leader s Overall Acceptance for the two radio conditions, a highly statistically significant effect was observed, F(1, 56)=59.44, p<.001. Where the no radio condition was rated between Borderline and Barely Acceptable, and the PRR condition was rated greater than Reasonably Acceptable. Therefore both groups of participants (Leaders and non Leaders) rated the Overall Acceptance similarly. Reference Figure 13. Humansystems PRR Evaluation Page 28

39 Completely Acceptable Reasonably Acceptable Barely Acceptable Acceptability Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable TCCCS Only PRR Radio Condition Mean Mean±SE Mean±SD Figure 13: Overall Acceptance (Leaders vs. Non Leaders) Statements of Importance Participants (Leaders and non Leaders) rated their agreement of importance on the following five statements on a progressive scale of 1 to 7 (Strongly Disagree=1, Reasonably Disagree=2, Barely Disagree=3, Neutral=4, Barely Agree=5, Reasonably Agree=6, and Strongly Agree=7). See Table 1. Table 1: Statements of Importance We were more effective as a team with the radio communication system than with the no-radio system. We were more aware of our situation with the no-radio system than with the radio comms system. Command and control were improved with the radio comms system, over the no-radio system. Command and control were improved with the no-radio system, over the radio comms system. All members of a dismounted infantry section should be provided with radio comms during a mission. Overall, participants were in reasonable agreement (greater than Barely Agree but less than Strongly Agree ) to the radio condition in terms of team effectiveness, and command and control tactics versus the no radio condition (less than Barely Disagree ). As well, participants Humansystems PRR Evaluation Page 29

40 were in reasonable agreement that all members of a dismounted infantry section should be provided with a radio during a mission. Reference Figure 14. Strongly Agree Reasonably Agree Acceptability Barely Agree Neutral Barely Disagree Reasonably Disagree Strongly Disagree Effective Tm w/ Radio Effective Tm w/ No Radio Cmnd/Cntrl w/ Radio Statements Cmnd/Cntrl w/ No Radio All Sldr Shld Hve Radio Mean ±SE ±SD Figure 14: Statement of Importance Importance of a Radio for Mission Phase Participants (Leaders and non Leaders) recorded their judgment of importance on the following five mission phases on a progressive scale of 1 to 7 (No Importance=1, Slight Importance=2, Little Importance=3, Some Importance=4, Moderately Important=5, Very Important=6, and Extremely Important=7). See Table 2. Table 2: Mission Phases Pre-Mission Briefing Advance to RV Approach Objective Assault Objective Consolidation Humansystems PRR Evaluation Page 30

41 Overall, the importance of a radio in the pre-mission briefing phase was judged less than the other four mission phases. Reference Figure 15. Participants felt that the radio was less than of Little Importance during the pre-mission briefing phase, but during the Advance to RV, Approach Objective, Assault Objective, and the Consolidation phases radios were judged to be greater than Moderately Important. Similar findings were observed in past PRR trials. Extremely Important Very Important Judgment of Importance Moderately Important Some Importance Little Importance Slight Importance No Importance Pre-Mission Apprch Obj Consolidatn Advnce RV Asslt Obj Mission Phase Mean ±SE ±SD Figure 15: Importance of a Radio for Mission Phase Importance of a Radio for Mission Features Participants (Leaders and non Leaders) recorded their judgment of importance on the following thirteen mission features on a progressive scale of 1 to 7 (No Importance=1, Slight Importance=2, Little Importance=3, Some Importance=4, Moderately Important=5, Very Important=6, and Extremely Important=7). See Table 3. Humansystems PRR Evaluation Page 31

42 Table 3: Mission Features Awareness of Friendly Forces Awareness of the Battle Situation Coordination within the Section Teamwork Issuing/Receiving Orders Passing Information Requesting Information Tempo of Mission Achieving Mission Timings Ability to Maintain Stealth Ability to Adapt to Unexpected Changes in Mission Minimizing Casualties Overall Mission Success Overall, participants rated the 'Awareness of Friendly Forces, Awareness of the Battle Situation, Passing Information, Requesting Information, Ability to Adapt to Unexpected Changes in Mission, and Overall Mission Success as the features most benefiting from the use of an intra-section radio. Reference Figure 16. Participants felt that the importance of a radio for these mission features was quite high: greater than or equal to Very Important. Humansystems PRR Evaluation Page 32

43 Extremely Important Very Important Judgment of Importance Moderately Important Some Importance Little Importance Slight Importance No Importance Awre Friend F Awre Bttle Sit Coord w Sectn Tmwork Issue/Rcve Ordr Passng Info Rqst Info Tmpo Missn Achve Missn Tme Maintn Stlth Mission Feature Adpt to Chnge Min Casualties Ovrall Succss Mean Mean±SE Mean±SD Figure 16: Importance of a Radio for Mission Features Acceptability of PRR Equipment Features Infantry Leaders and non-leaders rated the acceptability of PRR equipment features used in this experiment: the Radio, Headset and Remote Push-to-Talk (PTT) Acceptability of the PRR Radio With respect to the PRR Radio, participants rated on the following eighteen features listed in Table 4. All of the participant s scaled ratings (1 to 7) were tabulated, and means computed and analyzed. Humansystems PRR Evaluation Page 33

44 Table 4: PRR Radio Features PRR Radio Features Mean ± SD Acceptability Network Control Knob 5.9 ± 0.9 > Barely Acceptable Volume Control Knob 6.0 ± 0.8 Reasonably Acceptable Size 6.3 ± 0.7 > Reasonably Acceptable Weight 6.4 ± 0.7 > Reasonably Acceptable Carry Pouch 6.2 ± 0.6 > Reasonably Acceptable Antenna 6.1 ± 0.9 > Reasonably Acceptable Ability to Attach to Webbing 6.0 ± 1.1 Reasonably Acceptable Ability to Mount in Preferred Location 6.0 ± 1.2 Reasonably Acceptable Connection to Headset 6.0 ± 0.9 Reasonably Acceptable Connection to Commander Radio (if applicable) Ease of Changing Network Configuration (if applicable) Ease of Changing User Switches (Single or Dual) (if applicable) 5.8 ± 0.9 > Barely Acceptable 5.6 ± 1.4 > Barely Acceptable 6.0 ± 0.6 Reasonably Acceptable Ease of Operation of Radio PTT (if applicable) 5.9 ± 1.0 > Barely Acceptable Reliability of Radio System 5.2 ± 1.3 > Barely Acceptable Integration with Existing Kit 5.7 ± 0.9 > Barely Acceptable Range of Radio in Open Ground 5.3 ± 1.4 > Barely Acceptable Range of Radio in Wooded Areas 4.6 ± 1.7 > Borderline Range of Radio in Urban Areas 4.8 ± 1.8 > Borderline Overall, participants rated the acceptability of the PRR radio features greater than Borderline but less than Completely Acceptable. See Table 4 for a summary of the results. The PRR radio Network Control Knob, Volume Control Knob, Size, Weight, Carry Pouch, Antenna, Ability to Attach to Webbing, Ability to Mount in Preferred Location, Connection to Headset, Connection to Commander Radio, Ease of Changing Network Configuration, Ease of Changing User Switches (Single or Dual), Ease of Operation of Radio PTT, and Integration with Existing Kit were rated high in acceptability. Conversely the Reliability of the Radio System, Range of Radio in Open Ground, and Range of Radio in Urban Areas tended to be rated lower in acceptability. Reference Figure 17. This finding was reinforced by soldier comments where they found the PRR to be ineffective over undulating topography and in areas where clear line of sight could not be achieved (i.e. wooded terrain less than 50 m separation). Several soldiers also Humansystems PRR Evaluation Page 34

45 commented that radio communication within the urban village was intermittent. This may have been due to the concrete and metal building structures which impeded radio signal. Completely Acceptable Reasonably Acceptable Acceptability Barely Acceptable Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable Ntwrk Cntrl Knob Vol Cntrl Knob Size Wt Carry Pch Ant Attch Web Mnt Pref Locatn Cnnct Hdset Cnnct Cmmd Radio Ease Chnge Ntwrk Ease Chnge Swtch Ease Op PTT Reliability PRR Integrate w Kit Rnge Open Grnd Rnge Wooded Rnge Urban PRR Radio Feature Mean ±SE ±SD Figure 17: PRR Radio Feature Acceptability Acceptability of the PRR Headset With respect to the PRR headset, participants rated acceptability on the following seventeen features listed in Table 5. All of the participant s scaled ratings (1 to 7) were tabulated, and means computed and analyzed. Humansystems PRR Evaluation Page 35

46 Table 5: PRR Headset Features PRR Radio Features Mean ± SD Acceptability Fit of Earpiece 5.8 ± 0.9 > Barely Acceptable Comfort of Earpiece 5.7 ± 1.1 > Barely Acceptable Clarity of Earpiece Sound 6.0 ± 0.8 Reasonably Acceptable Ability to Adjust Headband 5.9 ± 0.9 > Barely Acceptable Comfort of Headband 5.8 ± 1.2 > Barely Acceptable Ability to Adjust Microphone 6.2 ± 0.7 > Reasonably Acceptable Ease of Microphone Use 6.2 ± 0.7 > Reasonably Acceptable Quality of Microphone Sound (calm) 6.1 ± 0.8 > Reasonably Acceptable Quality of Microphone Sound (wind) 5.9 ± 0.8 > Barely Acceptable Sensitivity of Microphone 5.9 ± 0.8 > Barely Acceptable Weight 6.4 ± 0.6 > Reasonably Acceptable Cabling 5.3 ± 1.5 > Barely Acceptable Size 6.1 ± 0.9 > Reasonably Acceptable Sound Quality 6.1 ± 0.8 > Reasonably Acceptable Ability to Maintain Local Situation Awareness 6.0 ± 0.7 Reasonably Acceptable Reliability of Headset System 6.0 ± 1.0 Reasonably Acceptable Compatibility with Helmet 5.6 ± 1.3 > Barely Acceptable Overall, participants rated their acceptability of the PRR headset features greater than Barely Acceptable but less than Completely Acceptable. The PRR headset cabling was rated lower in acceptability than all of the other PRR headset features. During focus group discussions, soldiers voiced concern over the short length of the PRR headset cable, as some soldiers preferred to place the PRR in other locations on the body rather than on the chest. As well, another concern was raised from some participants with respect to the fit of the earpiece and difficulties in achieving a comfortable fit under the CF helmet. Acceptability ratings from the Exit Questionnaire also reflected this trend, with the Fit of Earpiece, Comfort of Earpiece, Comfort of Headband, and Compatibility with Helmet features being rated slightly lower in acceptability than the other features. Reference Figure 18. Humansystems PRR Evaluation Page 36

47 Completely Acceptable Reasonably Acceptable Acceptability Barely Acceptable Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable Fit Earpiece Cmfrt Earpiece Clarity Sound Adjst Hdbnd Cmfrt Hdbnd Adjst Mic Ease Mic Use Qlty Mic Snd_calm Qlty Mic Snd_wind Sensitiv Mic Wt Cabling Size Snd Qlty Maintain Sit Aware Reliability Compat w Helmt PRR Headset Feature Mean ±SE ±SD Figure 18: PRR Headset Feature Acceptability Acceptability of the PRR Remote Push-to-Talk (PTT) With respect to the PRR remote PTT, participants rated their acceptability on the following four features listed in Table 6. Table 6: PRR Remote Push-to-Talk Features PRR Remote Push-to-Talk Features Mean ± SD Acceptability Ease of Operation 6.0 ± 1.1 Reasonably Acceptable Functionality of Attachment Strap 5.5 ± 1.6 > Barely Acceptable Reliability of PTT 4.8 ± 1.7 > Borderline Compatibility with Existing Kit 5.7 ± 1.3 > Barely Acceptable Overall, participants rated their acceptability of the PRR remote PTT features greater than Borderline but equal to or less than Reasonably Acceptable. Ease of Operation, Humansystems PRR Evaluation Page 37

48 Functionality of Attachment Strap, and Compatibility with Existing Kit tended to be rated higher in acceptability than the Reliability of PTT, which was rated less than Barely Acceptable. Reference Figure 19. The low reliability of the remote PTT was further reinforced by soldier comments during focus group discussions. Soldiers frequently reported that the PRR would intermittently cut-out transmission during the delivery of a message (every 2-3 s), and then the transmission would return to normal and then cut-out again in a predictable cycle. As well, the C9 gunners found the attachment strap of the remote PTT to be too short in length. Completely Acceptable Reasonably Acceptable Acceptability Barely Acceptable Borderline Barely Unacceptable Reasonably Unacceptable Completely Unacceptable Ease Op Reliable PTT Attchmnt Strap Compat w Kit PRR Remote PTT Features Mean ±SE ±SD Figure 19: PRR Remote PTT Feature Acceptability Humansystems PRR Evaluation Page 38

49 4.2 Lessons Learned The following lessons learned (LL), tactics, techniques and procedures (TTP s), and Soldier recommendations in this summary are based on findings from past and present SIREQ TD experiments, and also draw extensively on the United States Marine Corps, Marine Corps Warfighting Laboratory (MCWL), UK Government, and non-military publications. These findings may be combined with the current CF doctrine to provide best practices for this new item of Soldier equipment. The LL, TTP s, and recommendations are just that, experimentation findings and Soldier suggestions that will provide guidance in the operational employment of the PRR. Many more LL, TTP s, and recommendations will arise in the near future as Soldiers are deployed with the PRR Setup The following setup procedures are recommended to maintain effective communication with the PRR Radio: Mounting the PRR: It is recommended that the PRR be worn on the frontal torso on the left shoulder affixed to your inservice tactical vest. The radio should be placed vertically on the shoulder to allow for the maximum antenna transmittance and clearance (FBES 2002, 2003). The higher an unobstructed antenna, the better the signal transmission. Headset cord length: Several Soldiers suggested that the length of the headset cord should be increased to prevent it from snagging on equipment or to enable the PRR to be located elsewhere on the Soldier. However, the short cord length maintains good antenna transmittance and reduces the occurrence of signal shielding by the wearers own body (FBES, 2003). Humansystems PRR Evaluation Page 39

50 Channel Display Visibility: Initially the radio should be mounted in a manner where the channel dial will be visible to the Soldier. However, individuals should familiarize changing channels without visual feedback especially during night operations (FBES 2002, 2003). Microphone positioning: PRR waterproof specifications: The Electret noise-canceling microphone should be positioned 1 (max 2 ) away from the mouth in order to provide clear and intelligible communication. Stealth through whispered speech is best achieved with the microphone close to the mouth (FBES 2002). Position the microphone boom close to your cheek and mouth to minimize snagging and being seen in your peripheral vision (FBES 2002, 2003). The molded case provides protection against environmental hazards such as impact and immersion. Excluding the headset, the radio is fully functional after immersion in water for duration of 20 minutes (UK MoD, 2001) Remote PTT: Affixing the Remote PTT: The remote PTT switch should be positioned on the weapon so that Soldiers can transmit while keeping their hands on the weapon. Mounting to the forestock of the C7 rifle has proven to be the most effective position (see the figure to the left) (FBES 2002, 2003). Humansystems PRR Evaluation Page 40

51 Remote PTT Affiliation: Do not attempt to affiliate several radios within close proximity to one another at the same time. Ensure that a minimum 5 m separation is maintained so that the signal transmitted during affiliation will not be received by any other PRR. To ensure successful affiliation adhere to the following steps: Only program/associate one PRR at a time when within a close vicinity to another user. Make sure all other nearby PRR s are turned off when a user is performing an affiliation (FBES, 2002, 2003, UK MoD, 2001, and MCWL, 2003). Affiliating more than one radio at a time or having more than one radio turned on during the affiliation process will: Create cross-affiliations because several radios may become affiliated with one wireless PTT; or Radios will be affiliated with the wrong PTT Operation As previously stated the explicit intent of the PRR is as an intra-section radio. When establishing comms between Section Commanders and the Platoon Commander the TCCCS radio should still be used. The PRR is not appropriate for use above the Platoon level Channel Assignment: Net assignment: Net assignment is adjusted through the selector located behind the PTT switch assembly unit and is typically pre-set by communications personnel in accordance with the Commander s plan for PRR usage. Prior to mating the PRR PTT switch housing to the radio body and initial deployment, the group selection has to be readied. There are 256 possible channels (16 Groups while there are 16 channels in each Group). Normally individual Soldiers will not need to change the net selector setting but will rely on the range of 16 channels within the channel selection dial (FBES 2002, 2003, MCWL, 2003) Humansystems PRR Evaluation Page 41

52 PRR Channel Assignment: Low visibility operation: Depending on the mission, channel assignments could vary. For example, each Section could be assigned only one channel on the PRR for intra- Section communication between all Section members. One channel per Section works well for maneuvering in non-complex terrain and low tempo operations. In complex terrain and high tempo (e.g. urban CQB), one channel could be assigned to each assault group in order to support closer fire team coordination. The Section would then have two channels. The Section Commander should use the TCCCS radio system to coordinate actions between Sections and the Platoon Comd. The PRR should be used only as a backup for communicating outside of the Section (FBES 2002, 2003). Soldiers should become familiar with changing the channels without visual feedback. This will be an important skill especially during night operations (FBES 2002, 2003) Voice protocol: Voice procedure: The PRR procedures should follow the conventions of voice procedure on an insecure net. As well the noise-canceling microphone does not require any special instruction. As with any radio, do not shout into the microphone. Remember, an intra-section radio offers the Section the new advantage of verbal stealth, even in situations where there is no line-ofsight between sender and receiver. Yelling gives away your position and often your intentions (FBES 2002, 2003). Humansystems PRR Evaluation Page 42

53 Voice transmission: Soldiers need to be encouraged to use the PRR, become familiar with sound quality, and self voice transmission, especially in the initial practice stage. Inevitably, soldiers want to chatter on the new radios, so let them. With practice and experience, the soldiers quickly get familiar with the device, net traffic diminishes, and transmissions improve in both clarity and conciseness (FBES 2002, 2003). This practice is critical. Where possible Section practice should include two channels one channel for each assault group. The Section Comd and 2IC should be encouraged to become familiar with switching between the two Section channels. As well, the Section should practice protocols for signaling all section members to switch to one channel and then back to the assault group channels, as dictated by the tactical situation Range: PRR Communication Range: Urban Operations The following figure outlines communication range when 7-8 PRR s are deployed in and around a FIBUA building. Numbers indicated in the photos below correspond to spots where Soldiers can be located within a building while still maintaining communications to other Section members. Transmission can be made/received up to 150 m verified through 5 dwellings. Transmission can be made/received up through 3 floors in building. Humansystems PRR Evaluation Page 43

54 Using a Radio Relay: LL #1 Range (Defensive position) LL #2 Range (Range: <500 m) On many occasions intra-section communications were not effective due to range, terrain, physical obstacles and the PRR antenna being too close to the ground. When this occurs, try shifting from the prone position to kneeling, move away from obstacles if the situation permits, or turn to the direction of the person/unit with whom you are trying to communicate to establish maximal signal strength. If this approach still fails, use another fire team or Section member as a relay, and keep the message short and clear. If communications over out-of-range distances becomes mission essential, you can use the TCCCS radio to re-establish comms (FBES, 2002, 2003, and MCWL, 2003). Soldiers reported that a major tactical benefit of the PRR was the improvement in the capability of the Section and Platoon to remain concealed during information exchanges, thereby being less detectible to the enemy. For example, during the all-around defensive at an ORV, the PRR enabled Soldiers to clearly, and consistently, hear their commander s orders while being more widely dispersed and better concealed, while still retaining their battlefield situational awareness and continuing to observe their arcs. Section commanders did not need to walk from Soldier to Soldier passing information, resulting in faster passage of information, better comprehension by all soldiers, and a faster overall mission tempo (FBES 2002, 2003). Commanders need to practice using the PRR s for routine passage of information and reserve face-to-face interactions for essential situations only. In deadfall there was no problem with the radio signal reaching fire teams, but when there was no line of sight/bad terrain, PRR range was more constrained (sometimes the range was less than 50 m especially in wooded undulating terrain). In a dense wood line, even if you did have eyes on, Soldiers were occasionally able to see who they were trying to contact before they could transmit a message (FBES 2002, 2003). Humansystems PRR Evaluation Page 44

55 Improving transmission: TCCCS compatibility: Soldiers had difficulty plugging the PRR into the 521 and 522 however, some leaders found that they had to fiddle with the radios and it finally became functional when the 521 and 522 was switched onto high power (i.e. whisper mode) (FBES 2002, 2003). Call Waiting Feature with Dual Interface PRR s: Tips to Optimize Dual Interface PRR Communication: On dual switch PRR s operating with a Combat Net Radio (CNR): if a signal is received via the CNR while transmitting via the PRR, a call waiting signal comprising three medium length tones (- - -) repeated every 5 seconds will alert the operator until the PRR PTT is released. Only when the PRR PTT is released is the attached radio signal heard. To talk on the CNR, press the CNR PTT (UK MoD, 2001). if a signal is received from the CNR and the PRR is not transmitting, then the CNR signal will override the PRR signal even if there is communication traffic on the PRR. (This is based on the assumption that the attached radio has communication traffic from higher and is therefore more important. This may not be the case in some situations (MCWL, 2003). Establish SOPs to best use the dual interface PRR capability. One way of handling this situation is to have a vacant channel next to the operating channel on the attached radio so the user can switch to that channel if the communication on the PRR channel is more urgent than the attached radio channel (FBES, 2003, MCWL, 2003). Humansystems PRR Evaluation Page 45

56 Batteries: Batteries: Power consumption ratio Radio: 24 hours of operation at 1:7:16 (Tx/Rx/S BY) Remote PTT: Li-ion battery providing not less than 3000 hours use (UK MoD, 2001) LL #1 Batteries LL #2 Batteries PRR batteries under ideal conditions are rated for 24 hours of use. However, Soldiers should switch out the batteries before you think you need to (FBES, 2003). In cold weather, the duration of battery use will diminish further. Soldiers should always carry a spare set of AA batteries on their person (FBES 2002, 2003). Low Batt. Indicator: _ _ When the PRR tone indicator was disabled, there was no method in verifying the battery consumption level. User trials conducted by the UK MoD (2003) also reported problems with the low battery indicator. The time between battery low warning and battery failure was inadequately short (FBES 2002, 2003). Low visibility operation: Soldiers should become familiar with changing the batteries without looking at the radio. This will be an important skill especially during night operations (FBES 2002, 2003) PTT Issues: Remote PTT concern: Cutouts Soldiers observed that the remote PTT would transmit for approximately 3 seconds, cut out for a few seconds, and then transmit again for another 3 seconds. Similar to the findings by the UK PRR user trials (2003), the PTT is ideal and the preferred method as it eliminates problems relating to wire entanglement. However, in this particular case, the PTT does pose problems during continuous and prolonged transmissions (FBES 2002, 2003). Humansystems PRR Evaluation Page 46

57 Adjustability for C9 gunners: PTT band may require a supplementary strap (longer) in order to affix to the C9. The PTT band also needs to be more durable (FBES 2002, 2003) Security As with any piece of equipment, especially those employing voice/data transfer, proper SOP s should be strictly adhered to. The following is not a comprehensive list of security issues, but were items that were gathered from past and present trials, user recommendations, and various government and non-military publications. Security related to content of transmission: Encryption: As with any radio, you should restrict the nature of traffic over the PRR to guard against the following threats: Information collected from a number of channels used in the same unit may be combined to produce useful information. Recorded transmissions could be used as part of a deception plan. If many channels are used in a particular area, operational security may be compromised, particularly if radio silence has been imposed. Operational security may be compromised if information passed over a secure net is repeated over a PRR channel (MCWL, 2003 & UK MoD, 2001). The PRR does not have encryption but it uses Direct Sequence Spread Spectrum (IEEE at 2.4 GHz) technology, which sounds like garbled noise to an eavesdropper. The radio has good resistance against interfering signals and provides a Low Probability of Intercept (LPI) and Low Probability of Detection (LPD) (Flagship Training Limited, 1999). Short range: The limited range of the PRR (500 m rural terrain) provides security to some extent, although detection and interception may still be possible. (UK MoD, 2001) Humansystems PRR Evaluation Page 47

58 Information transfer: NOTE: To maintain transmission security, information of a sensitive nature should not be sent using the PRR: Orders of Battle HQ/unit locations (grids/location names) Areas of operation, boundaries, or demarcation lines Future intentions and plans Organizational names (UK MoD, 2001, and MCWL, 2003) Enemy capture:!! PRR communications are highly vulnerable if the enemy captures one of them. As with any radio, assume that any lost PRR is being used for passive interception and exploitation (MCWL, 2003) Additional Constraints and Recommendations The following list of additional PRR performance constraints and soldier recommendations is divided into several categories: Transmission, Remote PTT, Headset and Body PRR Transmission Priority cut off switch: With the TCCCS radio the Soldier in command always has priority and will cut into any transmission (ICS or intercom system). The PRR was not fitted with this capability so the transmitting of information was sometimes not effective. The PRR should have a capability where the Commanding Soldier always has transmission priority. Increase Range: >500 m As previously discussed, when there was no line of sight/bad terrain, PRR range was more constrained. The solution may be to allow the soldier to alter the signal strength by increasing the output in non-ideal terrain to improve signals (similar to TCCCS). Compatibility with CF radio: As previously mentioned, Soldiers had difficulty plugging the PRR into the 521 and 522. The UK MoD PRR trials (2003), also reported dual role problems, however, did not further elaborate. This may be a function of compatibility and should be further addressed. Humansystems PRR Evaluation Page 48