A study on coherently combining sparse-multiband processing

The authors proposed Coherently Combining Sparse-Multiband Processing (CCSMP) [1], which coherently combines signals of the separated multi-band obtained by the stepped multiple frequency method [2]. CCSMP implements the Recursive Signal Subtraction Frequency Estimation Method [3], which iteratively estimates the range of each target while separating the signals one by one from the observed signals from multiple targets obtained in each band. Hence, CCSMP can improve the range estimation performance in multiple-target situations where the main lobes of the targets overlap and interfere with each other. In this letter, we derive the Cramer-Rao Lower Bound (CRB) for the target range estimation by combining the separated multi-band signals, and the performance of CCSMP is discussed by comparing the derived CRB values with statistical evaluations by simulation.