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arXiv · 2509.13287

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

Nandan Sriranga·Haodong Yang·Venkata Gandikota·Pramod K. Varshney
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Abstract

We address target detection in a single Delay-Doppler cell using spatially distributed two-channel passive radars. An unknown illuminator of opportunity (IO) is assumed to emit a waveform lying in a known low-dimensional subspace (e.g., OFDM). Each receiver transforms its reference and surveillance signals onto the IO subspace after noise-whitening, to obtain cross-correlation (CC) measurements. To save bandwidth, receivers collaboratively exchange and linearly combine the CC output, and only a subset transmits them to a fusion center (FC) over a multiple-access channel (MAC). Collaboration weights are designed using the moments of the FC measurement to enhance detection performance.

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Nandan Sriranga, Haodong Yang, Venkata Gandikota, Pramod K. Varshney. 2025-09-16. Target Detection in Two-Channel Passive Radars with Inter-Receiver Collaboration. https://arxiv.org/abs/2509.13287

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