Structure-Aware Bayesian Compressive Sensing for Frequency-Hopping Spectrum Estimation with Missing Observations

In this paper, we address the problem of spectrum estimation of multiple frequency-hopping (FH) signals in the presence of random missing observations. The signals are analyzed within the bilinear time-frequency (TF) representation framework, where a TF kernel is designed by exploiting the inherent FH signal structures. The designed kernel permits effective suppression of cross-terms and artifacts due to missing observations while preserving the FH signal auto-terms. The kernelled results are represented in the instantaneous autocorrelation function domain, which are then processed using a re-designed structure-aware Bayesian compressive sensing algorithm to accurately estimate the FH signal TF spectrum. The proposed method achieves high-resolution FH signal spectrum estimation even when a large portion of data observations is missing. Simulation results verify the effectiveness of the proposed method and its superiority over existing techniques.Comment: 14 pages, 11 figures, to appear in IEEE Transactions on Signal Processin

Hop Timing Estimation for Noncoherent Frequency Hopped M-FSK Intercept Receivers

The optimum hop timing estimator (based on likelihood-ratio (LR) theory) is derived for noncoherent slow and fast frequency-hopped intercept receivers. Such receivers have no a priori knowledge of the hopping code and thus the solution to this estimation problem differs considerably from the more commonly considered case of the friendly receiver. The implementation and performance of the LR hop timing structures are presented and compared with that of other schemes that have been discussed in the literature. `This work was performed by the Jet Propulsion Laboratory, California Institute of Technology, under a contract with the National Aeronautics and Space Administration sponsored by the U.S. Army Intelligence & Electronic Warfare Directorate and in part by the University of Southern California, sponsored by the Joint Services Electronics Program, Contract No. F49620-91-C- 0028, Hop Timing Estimation for Noncoherent FrequencyHopped Intercept Receivers Marvin K. Simon, Fellow IEEE..