TECHNOLOGY AREA(S): ElectronicsOBJECTIVE: To design, fabricate, and demonstrate a radar early warning receiver for the dismounted soldier's uniform, armor or battle kit that identifies and locates a Ground Surveillance Radar (GSR) threat.DESCRIPTION: In the modern operating theater the dismounted warfighter faces a network of sensors searching from fixed and mobile ground and air platforms. Ground Surveillance Radar (GSR) or Battlefield Surveillance Radar (BSR) are long range sensor threats that can identify and track ground movement over kilometer scale distances, posing a threat of the maneuverability, survivability and ultimately the lethality of dismounted units. The ability to detect a GSR at a distance greater than its maximum range will turn the squad into a distributed sensor to locate advisory assets and take appropriate action.Commercial GSR systems advertise single dismount detection ranges up to 23km [1]. With smaller man portable systems able to detect 12km with traditional pulse Doppler [2] or 9km with low probability of intercept (LPI) frequency modulated continuous wave (FMCW) [3]. Systems are also available coupled with day/night electro-optical sensors [4]. Threat systems are line of sight and maximum ranges assume systems are placed at sufficient elevation.To contour the availability of these long-range systems the Government requires a radar early warning receiver for the individual dismounted soldier. Due to the ever-growing number of threats and potential technological capabilities for the dismounted warfighter, the Government must manage the total soldier burden of adding additional equipment to the battle kit. The Government therefore requires that this radar early warning receiver be a low profile integrated part of the uniform, armor or kit rather than an additional item mounted on the warfighter. The design should consider options such as wearable antennas and flexible electronics while considering associated challenges with these technologies for X and Ku Band (8-18 GHz) operation. The system shall intercept and identify a GSR threat at a distance greater than its maximum range for detecting a single dismounted person. The system should also be capable of finding the angle of arrival of the GSR signal and estimate the location of the emitter. Output will integrate with the Android Tactical Assault Kit (ATAK), a government owned mapping application, for communicating with the soldier. All members of a squad of 9 soldiers will have the receiver and will be networked through Bluetooth.PHASE I: Phase I must show the feasibility of the technical approach through a demonstration of the preliminary designs including breadboard or demonstration board of electronic components, signal processing, electronic integration with uniform, armor, or soldier kit, and detailed plans for placement as well as size, weight and power. The sensor should capture sufficient information to identify the GSR system from a library of waveforms. It must also be able to find angle of arrival and estimate of the location relative the user. The system must perform for signals in the X and Ku Bands (8-18 GHz). It is not necessary to demonstrate the integration of the technology into a complete system, however, the planned technical approach and feasibility for system integration for Phase II must be included. Phase I deliverables will include, (1) a final report detailing technical approach, design, implementation, tests, data analysis, conclusions, and proposed path for integration with the soldier's kit. (2) All test data. (3) A working breadboard prototype with software. Phase I deliverables do not have to be implemented on ATAK but this will be a requirement of subsequent phases.PHASE II: Phase II will produce a prototype of a soldier worn radar early warning receiver that identifies and locates a Ground Surveillance Radar (GSR) threat. The system shall discriminate the threat from other radio frequency (RF) sources. The system shall be a low profile integrated part of the soldier's kit rather than an additional item mounted on the warfighter. The system shall intercept and identify a GSR threat at a distance greater than its maximum range of detection for a single dismounted person. The system shall find the angle of arrival of the GSR signal and estimate the location of the emitter. Assume that the system is worn by all members of a 9 soldier squad. Location estimations shall improve as successive samples are collected and from aggregation of data from the detectors worn by all members of the squad. Software shall be implemented on the ATAK mapping platform and display to the user an estimation of the GSR location and detection range. The system must be ruggedized to operate in all operationally relevant environments, -30 125oF high and low humidity, rain, dust, fog, etc. However, it must still be a low profile integrated part of the uniform, armor or kit rather than an additional item mounted on the warfighter. The system must operate in a cluttered RF environment with many signals and sources of electromagnetic interference. The final deliverable must also include an assessment of viability of producing the developed technology including an estimated system price.Phase II deliverables will include, (1) a critical design review in which the contractor will provide in depth details on the design or their prototype system. (2) 4 copies of the prototype soldier worn radar detector system implemented on a smart phone running ATAK. (3) Source code for the ATAK application. (4) A final report detailing technical approach, design, implementation, tests, data analysis, and conclusions. (5) All test data.PHASE III: Phase III will demonstrate the operability, and reliability in field tests. It will be used to warn soldiers of the presence of a GSR threat, identify the threat while discriminating it from other RF signals, estimate location and range of the GSR source, arrogate data from sensors worn by all members of a 9 soldier squad to refine location estimation, display threat information to the user through an ATAK application, and relay information back to higher level command and control. The result of this research will be the integration of counter radar technology into the soldier's existing uniform, armor or kit which will improve their survivability and lethality through a multifunctional materials that minimize additional burden.KEYWORDS: Radar, Radar Detector, Radar Early Warning Receiver, Wearable ElectronicsReferences:1. THALES Observer 80, https://www.thalesgroup.com/sites/default/files/database/document/2019-03/2019_GO80_leaflet.pdf;2. SR Hawk Ground Surveillance Radar , https://www.srcinc.com/pdf/Radars-and-Sensors-SRHawkV2E.pdf;3. THALES SQUIRE Ground Surveillance Radar, https://www.thalesgroup.com/sites/default/files/database/d7/asset/document/03_p185749_thales_squire_leaflet.pdf
