Using DCFT for Multi-Target Detection in Distributed Radar Systems with Several Transmitters

TL;DR

This paper proposes a DCFT-based scheme for detecting multiple targets in distributed radar systems using pseudo-orthogonal waveforms, effectively addressing the near-far problem and improving detection of weak signals.

Contribution

The work introduces a novel successive cancellation method in the DCFT domain for multi-target detection in distributed radar with pseudo-orthogonal waveforms, enhancing weak target detection.

Findings

Effective detection of weak targets demonstrated through simulations

Successive cancellation improves detection accuracy in near-far scenarios

DCFT-based approach efficiently handles multiple targets with pseudo-orthogonal signals

Abstract

In distributed radar systems, when several transmitters radiate simultaneously, the reflected signals need to be distinguished at the receivers to detect various targets. If the transmit signals are in different frequency bands, they require a large overall bandwidth. Instead, a set of pseudo-orthogonal waveforms derived from the Zadoff-Chu (ZC) sequences could be accommodated in the same band, enabling the efficient use of available bandwidth for better range resolution. In such a design, special care must be given to the 'near-far' problem, where a reflection could possibly become difficult to detect due to the presence of stronger reflections. In this work, a scheme to detect multiple targets in such distributed radar systems is proposed. It performs successive cancellations (SC) starting from the strong, detectable reflections in the domain of the Discrete Chirp-Fourier Transform (DCFT) after compensating for Doppler shifts, enabling the subsequent detections of weaker targets which are not trivially detectable. Numerical simulations corroborate the efficacy and usefulness of the proposed method in detecting weak target reflections.