Resource-efficient parametric recovery of linear time-varying systems

This paper presents a novel, resource-efficient method of identifying the parametric description of linear, time-varying (LTV) systems, consisting of time shifts, frequency shifts, and complex amplitude scalings. Linear Frequency Modulation (LFM) waveforms are used to probe the system, and the returns are used to identify the parametric description. The number of samples required for perfect recovery is shown to scale linearly in the number of descriptive parameters K, and the sampling rate required is sub-Nyquist when compared to the bandwidth of the LFM waveforms. The time-bandwidth product of the LFM waveforms scales quadratically in K. Numerical examples demonstrate perfect recovery of closely spaced targets in the delay-Doppler space.