Target Detection in Two-Channel Passive Radars with Inter-Receiver Collaboration

We address the problem of target detection using spatially distributed two-channel passive radars. The transmitter is assumed to be an unknown illuminator-of-opportunity (IO), which transmits a waveform lying in a known low-dimensional subspace (e.g., OFDM). Each receiver transforms its reference and surveillance signals into the IO-subspace, to obtain cross-correlation (CC) measurements. To save bandwidth, receivers collaboratively exchange and linearly combine the CC outputs, after which only a subset of the receivers transmit to a fusion center (FC), over a multiple-access channel (MAC). The collaboration weights are designed to enhance detection performance. Simulation results are provided to illustrate the performance of the proposed framework.