Maximum Unambiguous Frequency Of Random Pri Radar

The echo signal of random PRI(pulse repetition interval) radar is sampled nonuniformly in pulse dimension. Aimed at the maximum unambiguous frequency of random PRI radar, we study the periodicity of nonuniform sampling spectrum and provide a formula to compute the aliasing frequency for nonuniformly sampled data which is equivalent to maximum unambiguous frequency of random PRI radar. Besides, we prove that because of the nonuniformity of sampling, the aliasing frequency is greater than or equal to mean sampling frequency. The equality holds when the sampling time distributes uniformly. It means that the aliasing frequency is "enlarged" because of the nonuniformity and the aliasing frequency in uniform sampling is a special case of the nonuniform sampling. After that, we discuss the characteristics of random PRI radar coherent processing including aliasing-free detection in Doppler domain and selection of Doppler channel. Numerical results are provided to illustrate the correctness of the conclusions above.