OUSD (R&E) CRITICAL TECHNOLOGY AREA(S): Integrated Sensing and Cyber The technology within this topic is restricted under the International Traffic in Arms Regulation (ITAR), 22 CFR Parts 120-130, which controls the export and import of defense-related material and services, including export of sensitive technical data, or the Export Administration Regulation (EAR), 15 CFR Parts 730-774, which controls dual use items. Offerors must disclose any proposed use of foreign nationals (FNs), their country(ies) of origin, the type of visa or work permit possessed, and the statement of work (SOW) tasks intended for accomplishment by the FN(s) in accordance with the Announcement. Offerors are advised foreign nationals proposed to perform on this topic may be restricted due to the technical data under US Export Control Laws. OBJECTIVE: Develop a system capable of increasing the range to up to 50 miles of an air-to-air or air-to ground data connection of at least 1mb/s while using a mobile ad hoc network (MANET) commercially available radio operating in the S-band on a large (>300 lbs GTOW) unmanned aerial system (UAS). DESCRIPTION: Numerous government and commercial groups have experienced the multitude of benefits of MANET radios operating in the S-band to control and communicate with other systems and operators. Unfortunately, the current range of the systems these types of radios are currently integrated into limit their operational capabilities. Currently most operations are conducted at a range of less than five miles, but the capability of something like air launched small UAS exceed this by orders of magnitude. They are unable to exercise this range because of this limitation and have been mostly relegated to close-in surveillance roles where their loiter time is still useful. For several existing current and future operations, a greater stand-off between a small UAS or a ground system and a larger airborne asset it is communicating with is greatly desired. The operational benefits of MANET radios are enough to continue utilizing them, but the government needs to develop a system to increase their range to meet emerging needs. The technical challenges include the limitations of staying in the S-band for data transmission, integration into existing UAS where size, weight, power, and drag penalties can cause issues, and the difficulties of receiving and transmitting signals from a moving airborne platform that is constantly changing in orientation with what it is attempting to connect to. Previous efforts to address this problem have mostly utilized off the shelf omni-directional antennas in systems that are designed to provide an excellent (>10mb/s) link at a short range. The actual requirements for command and control or streaming surveillance video require a much smaller rate and the need is to develop a system to focus on range instead of a higher data rate than is actually required for a mission. A number of larger systems are integrating beyond line-of-sight systems that use other communications networks to pass data between MANET nodes but that cannot be a solution for this problem because the other air and ground based units are already fielding S-band radios. Any technological approach to increase the range of an S-band radio is welcome, with the only restriction being a requirement for all transmitted data to be encrypted in accordance with AES 256. The contracting timeline for this effort would follow along behind an internal AFRL effort to build and test a prototype on an operational MQ-9 with the current state of the art antenna and benchmarking its capabilities. The feedback from the operational user as well as the technical results would be used to scope the Phase 2 to address the shortcomings of those tests and expand the capability. PHASE I: This is a Direct to Phase 2 (D2P2) topic. Phase 1 like proposals will not be evaluated and will be rejected as nonresponsive. For this D2P2 topic, the Government expects that the small business would have accomplished the following in a Phase I-type effort via some other means (e.g. IRAD, or other funded work). It must have developed a concept for a workable prototype or design to address at a minimum the basic capabilities of the stated objective above. Proposal must show, as appropriate to the proposed effort, a demonstrated technical feasibility or nascent capability to meet the capabilities of the stated objective. Proposal may provide example cases of this new capability on a specific application. The documentation provided must substantiate that the proposer has developed a preliminary understanding of the technology to be applied in their Phase II proposal to meet the objectives of this topic. Documentation should include all relevant information including, but not limited to technical reports, test data, prototype designs/models, and performance goals/results. PHASE II: Develop and demonstrate a system to communicate data reliably over a commercial S-band MANET radio air-to-air from a large UAS to another airborne system or a ground-based operator at a range of at least 50 miles. i. Develop and demonstrate a system, compromised of one or more pieces of equipment, that is capable transmitting data at 1mb/s from a large UAS to a ground-based operator or another small UAS over S-band ii. The system should account for differing orientations between the airborne asset it is installed on and the ground-based asset or small UAS it is communicating with iii. Develop matrix of operational tradeoffs relating to employing the new system that includes impacts of power consumption, cost, weight, and size iv. Generate Interface Control Document (ICD) and overview descriptions in parallel with the system development. v. System needs to be encrypted or easily capable of being encrypted using AES 256. Complete the design of the system, demonstrate performance of a prototype system through field testing, and deliver the prototype for subsequent evaluation by the government. PHASE III DUAL USE APPLICATIONS: The Government has an interest in transition of the demonstrated concept to large UAS operations for both surveillance and strike missions. Solutions may also have applications to commercial crop survey operations and disaster or forest fire response. REFERENCES: 1. Perez, Mariano Negron, SAR Image Formation with embedded QPSK communications in LFM guardbands and UAV antenna characterization https://apps.dtic.mil/sti/citations/AD1173453 2. Paula Paloma Sanchez Dancausa, Jose Luis Masa-Campos, Pablo Sanchez Olivares, and Eduardo Garcia Marin, "Omnidirectional Conformal Patch Antenna at S-Band with 3D Printed Technology," Progress In Electromagnetics Research C, Vol. 64, 43-50, 2016. 3. J. Peng, W. Tang and H. Zhang, "Directional Antennas Modeling and Coverage Analysis of UAV-Assisted Networks," in IEEE Wireless Communications Letters, vol. 11, no. 10, pp. 2175-2179, Oct. 2022 KEYWORDS: antennas, conformal antennas, directional antennas, S-band, MANET, UAV, communications, command and control, long range, small UAS
