Frequency-Switching Sparse Arrays

In this paper, we propose high-resolution target direction-of-arrival (DOA) estimation using frequency-switching sparse arrays which implement multi-frequency sparse arrays in a low-complexity manner. Unlike multi-frequency sparse arrays which require processing of wideband signals comprising multiple frequency components, the proposed frequency-switching sparse arrays only need to process a single-frequency component at any time instant, thereby eliminating such hurdles and significantly reducing the system complexity. A frequency-switching sparse array achieves the same number of degrees-of-freedom as a multi-frequency counterpart with comparable DOA estimation performance. Numerical results on the DOA estimation performance and Cramer- Rao bounds are provided to illustrate the effectiveness of the proposed frequency-switching sparse arrays.