No abstract

The growing interest in adopting pulse compression waveforms to non-coherent radar and radar-like systems (e.g. lidar) invites this update and review. The authors present different approaches of designing on-off {1, 0} coded envelopes of transmitted waveforms whose returns can be envelope detected and non-coherently processed. Two approaches are discussed for the aperiodic case: (a) Manchester encoding and (b) mismatched reference. For the periodic case, on-off sequences are described, which produce perfect periodic cross-correlation when cross-correlated with one or more integer number of periods of a two-valued reference sequence {1, −b}. This study provides comprehensive rules for designing periodic on-off waveforms and their references. The periodic waveform's highaverage duty cycle (over 50%) makes it a 'quasi continuous wave (CW) non-coherent waveform', which avoids the pulse-train conflict between average power and unambiguous range. Good experimental results with a laser range finder are presented. Reports on other uses are quoted.

No abstract

In monostatic continuous wave (CW) radar the dominant waveform is periodic linear frequency modulation, mostly because its stretch processing requires sampling rate much lower than the bandwidth. In a bistatic scene a clean copy of the transmitted signal, required in stretch processing, is not available to the receiver. That opens the competition for other periodic waveforms. The authors study describes and demonstrates, through bistatic field trials, the good performances of bi-phase and tri-phase CW waveforms. Among their advantages are sidelobe-free range response, availability at all prime lengths and ease of synchronisation. Successful bistatic operation is a prerequisite for multistatic systems.