Study on non-linear stepped chirp radar system

The linear stepped chirp radar suffers from (a) signal-to-noise ratio (SNR) losses due to amplitude weighting used to suppress nominal range sidelobes both in sub-pulse and inter-pulse compression and (b) range ambiguities due to periodicities in the inverse discrete Fourier transform (IDFT). The paper analyses the root cause of range sidelobes and proposes a new easily realizable non-linear stepped chirp waveform which achieves low sidelobes without incurring the SNR loss associated with conventional sidelobes suppression techniques. An alternatively DFT processing is introduced which can achieve both unambiguous velocity and high resolution ranging under HPRF mode. Simulation results have been given to prove this scheme.