Waveform design based on phase conjugation and time reversal

The recent development of the full digital array technology paves the way to the design of multistatic RADAR systems relying on agile waveforms at emission. This new paradigm fits perfectly with the concept of phase conjugation (or time reversal if applied to large-band data). This technique allows indeed to adaptively build a wave focusing onto a target, leading to an improvement in detection range or in search time as compared to classical approaches. The DORT method, issued from phase conjugation, even permits to detect multiple targets from the knowledge of the multistatic matrix of the antenna array. Based on both a theoretical analysis and an experimental proof provided here, it appears that these methods appear as very promising, especially for cueing and ultra-fast reacquisition modes where the phase conjugation/DORT SNR requirements are more easily fulfilled.