Multiple-input multiple-output over-the-horizon radar beamforming with uniform circular arrays

Multiple-input Multiple-output (MIMO) radar is a new radar system which utilizes multiple antennas at both the transmitting side and the receiving side. In order to suppress the spread-Doppler sea clutter and eliminate the multipath and multimode clutter when detecting slow-moving ships, some OTHR researchers began to propose that applying the technology of MIMO radar to the next generation of sky-wave OTHR. It reaches this by MIMO beamforming which can be formed on both transmit with non-causal adaptive beamforming and receive and uses this transmit and receive 2D selectivity as the basis of a strategy for minimizing spread-Doppler sea clutter and the multipath and multimode clutter. Uniform linear arrays (ULA) can only use one-dimension in azimuth which is the main array in current generation OTHR systems. This paper considers introducing uniform circular arrays (UCA) in OTHR and we apply MIMO adaptive non-causal beamforming to UCA to achieve elevation filtering capability. Theoretical analysis and simulation results have been presented.