Didtributed Aperture Demonstration

Compared to conventional radars, distributed aperture radars (DAR¡_s) have the potential to provide significantly improved detection, tracking and discrimination performance in severe EMI and clutter environments. Realizing this greater capability will require unique waveform selection and signal processing approaches. The objectives of this research project are: (1) to complete the development and validation of a computer simulation capability that will permit the analysis of these waveforms and interference rejection algorithms for DAR systems and (2) to experimentally validate the EMI simulation of Phase I. For example, DAR¡_s can potentially provide significantly improved target tracking accuracy because of the large baseline between the various apertures. The resulting angular resolution can be orders of magnitude better than the resolution of a monolithic system (single large radar). The same angular resolution can provide improved interference rejection. In Phase I, a high-fidelity sensor simulation was developed and was employed to investigate EMI rejection for various DAR concepts. A waveform/processing approach using simultaneous orthogonal waveforms was shown to effectively reject EMI from all angles. Phase II will extend that simulation capability to investigate adaptive processing for rejection of interference in EMI, clutter and joint EMI/clutter environments. The ability of orthogonal waveforms and adaptive processing to reject EMI near the target will be demonstrated by a ¡°rooftop¡± experiment. This experiment will be performed at the Air Force Research Laboratory¡_s Rome Research Site (AFRL/RRS) using their facilities where appropriate to achieve our objectives in a cost-effective manner. This experiment will also support AFRL/SNRT¡_s waveform diversity technology program. A letter from AFRL/SNRT affirming the use of GFE for this demonstration is included in the proposal.