Multirate processing using nested sampling

This paper describes the multirate processing of random signals sampled on nested intervals. Nested sampling intervals consist of nonuniformly spaced samples formed by concatenating two or more smaller intervals each with uniform sampling. By filtering a vectorized version of the signal power spectral density matrix, the input-output behavior of conventional filter banks can be replicated. This type of processing is especially useful in multifunction radars that must perform multiple tasks simultaneously but lack the capability to form multiple beams on receive. By performing Doppler processing for a given mainbeam pointing direction using only a sparse subset of uniformly transmitted pulses, the radar is able to point the mainbeam in other directions and execute different tasks in a time-multiplexed fashion. Simulated examples are presented which describe the application of the proposed technique.