TDC Based Radar Signal Reconstruction from Periodic Nonuniform Samples

For the universal radar signal acquisition system design, to solve the problem of nonuniform sampling resulted from the fact that sample clock can´t be divided exactly by radar pulse repetition frequency (PRF), a TDC (time-to-digital converter) based radar signal reconstruction method was presented. First, this paper proves that the nonuniform sampling can be modeled as periodic nonuniform sampling (PNS) process. Then assuming the time offsets are known, a new PNS reconstruction algorithm is derived. The new algorithm has the advantage that it can be used to perfectly reconstruct both even and odd order PNS signal. Besides, the algorithm can be calculated faster because it has a Hermitian Toeplitz matrix A. By integrating the TDC circuit in universal radar signal acquisition system, the sampling time offsets can be recorded, thus the real radar signal can be perfectly reconstructed from original non-uniform samples. Finally, the method is validated by computer simulation.