Co-Site Interference Mitigation for Wideband Receivers
Navy SBIR 2014.2 - Topic N142-118
ONR - Ms. Lore-Anne Ponirakis - email@example.com
Opens: May 23, 2014 - Closes: June 25, 2014
N142-118 TITLE: Co-Site Interference Mitigation for Wideband Receivers
TECHNOLOGY AREAS: Information Systems, Sensors, Electronics
ACQUISITION PROGRAM: Future EW programs including SIRFSUP FNC, an FY15 start
RESTRICTION ON PERFORMANCE BY FOREIGN NATIONALS: This topic is "ITAR Restricted". The information and materials provided pursuant to or resulting from this topic are restricted under the International Traffic in Arms Regulations (ITAR), 22 CFR Parts 120-130, which control the export of defense-related material and services, including the export of sensitive technical data. Foreign nationals may perform work under an award resulting from this topic only if they hold the "Permanent Resident Card", or are designated as "Protected Individuals" as defined by 8 U.S.C. 1324b(a)(3). If a proposal for this topic contains participation by a foreign national who is not in one of the above two categories, the proposal may be rejected.
OBJECTIVE: Provide >50 dB of steep skirted spectral rejection, tunable over many octaves, and ideally of tunable bandwidth to reject signals that would otherwise desensitize the receiver.
DESCRIPTION: Enemy jammers and co-site interferers impair the ability of wide band, sensitive receivers to operate effectively. These receivers are essentially needed for continuously monitoring the entire radio frequency (RF) spectrum (DC to >100 GHz) by our military. Significant advances have been made recently to increase the receiver's instantaneous bandwidth and sensitivity. However, their dynamic range is still insufficient to withstand these unwanted signals. A solution will enable STAR, simultaneous transmission and reception. A "system on a chip" combination of a set of tunable analog band-reject filters with sensitive and wide band RF digitizers is sought. The analog filters should have variable rejection bandwidth and minimal passband attenuation so as not to deteriorate the overall receiver sensitivity. The desired tuning speeds are < 1 microsecond. Integration of the filters with the digitizers will improve their performance and decrease size, weight and power (SWaP), but they also must match the linearity of the RF digitizers. If subspectral channelization is proposed, the ideal channels would span approximately 0-6 GHz, 6-20 GHz, and 20-110 GHz.
PHASE I: Determine the technical feasibility of the approach defined in the Phase I proposal to meet the performance requirements listed in the description for at least one of the indicated sub-channels. This feasibility could be demonstrated by actually making an integrated chip and measuring that. Alternatively and more likely, the parts that would be combined in the actual chip would be combined by either full numerical simulation using calibrated empirical models of the devices or first principle analytical models of their performance. The Phase II proposal must define the design concepts to be used and key component technological milestones, and relate these to the projected performance for all the proposed spectral channels. Assuming Phase I base is successful, during the Phase I option move the design of the first channel unit toward experimental reality and begin testing as time and funding allows.
PHASE II: Produce prototype hardware based on Phase I work that delivers the wideband tuning performance indicated in the description. Design, manufacture, integrate, and demonstrate the operation of a prototype in order to establish its performance parameters through experimentation at the contractor facility. Offer a test demonstration at a CONUS government facility to US Government researchers and user representatives. The prototype must include provision of a mechanism for determining the desired location of the notch filter and for achieving tuning of the filter to that spectral location. It is possible that the Phase II will include some classified work.
PHASE III: Complete design optimization across the entire spectrum while simultaneously integrating the Phase II developed co-site interference rejection system prototype into a military transceiver/receiver system of wide band character. Demonstrate its improved jamming resistance against narrowband, inherently wideband, and a combination of such jammer types, bursty and continuous wave in operation. Transition into an FNC or directly into a program of record would follow.
PRIVATE SECTOR COMMERCIAL POTENTIAL/DUAL-USE APPLICATIONS: As the density of commercial wireless signals continues to increase, spectral sharing schemes such as Dynamic Spectral Allocation will become more ubiquitous and the time allowed to respond to a forced carrier center move will drop. While changing spectral positions, the proposed tunable filters will allow continued data through-put rather than requiring suspension of service ("Make then break"). The wide bandwidth of the tuning range will allow a single unit to service the multiple bands required to provide service worldwide at a low system assembly cost.
2. IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, Vol. 61, No. 9, September 2013.
KEYWORDS: Tunable filters; wide band RF systems; adaptive systems; reconfigurable analog filters; co-site interference; jamming