DETECTION AND TRACKING OF MULTIPLE TARGETS USING DUAL-FREQUENCY INTERFEROMETRIC RADAR

Multiple-target tracking (MTT) usually requires either a network of distributed radars at different locations or single radar installed with expensive phased arrays. The moving targets with small radial velocity cannot be localized/tracked in 2-D space using single Doppler radar without an antenna array. To overcome this problem, we propose a new MTT method using dual-frequency interferometric radar. Targets’ detection is performed based on the range-Doppler map, while tracking is accomplished by extracting radial and angular velocities from time-varying Doppler and interferometric spectrogram, respectively. However, the presence of multiple moving targets in radar field-of-view (FoV) generates nuisance intermodulation terms in the interferometric response. The dual-frequency interferometric radar is capable of resolving this issue by transmitting high frequency waveforms for radial velocity extraction and low frequency waveforms to extract angular velocity while suppressing intermodulation terms. The correct association between 2-D velocities of each target is performed by determining initial direction of arrival (DOA). The Global Nearest Neighbor (GNN) method for measurement-to-track association is followed by modified gain extended Kalman filter (MGEKF) to estimate the state of each target separately. The proposed algorithm is simple to implement in practice and removes the need of radar network and complex array processing techniques. Extensive simulation results have been presented to evaluate the performance of the proposed algorithm in terms of root mean square error (RMSE) in state and trajectory estimation.