A General FRI Sampling System for Pulse Streams and the Multichannel Synchronization Method

Pulse streams are a kind of finite rate of innovation (FRI) signal that widely exist in many engineering applications. According to the FRI theory, nonconsecutive sampled Fourier coefficients (FCs) have better parameter estimation effects than the consecutive ones. In this brief, we propose a general FRI sampling system for pulse streams based on multichannel random modulation (MRM). Jointly using multichannel samples, multiple sets of consecutive FCs of distinct frequency bands can be analytically calculated by solving the least-squares problems. The minimum sampling rate for each channel is determined by the number of pulses rather than the pulse bandwidth. The proposed sampling system is general for pulses of distinct frequency bands, and we extend it to the frequency-agile radar (FAR). Besides, the multichannel synchronization problem is analyzed, and a calibration method when the pseudo-random sequences (PRSs) are not synchronized is proposed. Simulation experiments demonstrate the effectiveness of the proposed sampling system.