Joint Range and Doppler Estimation with Amplitude Weighted Linearly Constrained Minimum Variance Method for OFDM-based RadCom Systems

Recently, the joint operation of radar and communication (RadCom) systems becomes popular and an orthogonal frequency division multiplexing (OFDM) signal can be used to realize this system. In order for an OFDM-based RadCom system with high performance, accurate range and Doppler estimation needs to be achieved. For this purpose, the DFT method, which can be implemented very fast, is used commonly. However, this method greatly suffers from high sidelobes such that the weak target could get masked. The estimation results become even worse in the strong clutter case. To deal with this problem, an amplitude weighted linearly constrained minimum variance (AW-LCMV) method is proposed. In our proposed AW-LCMV method, the problem of high sidelobes is well handled by fully exploiting the target information in the range-Doppler domain and adding a regularization term on the range dimension. In turn, much better estimation results can be obtained by the AW- LCMV method. Finally, excellent simulation results are used to demonstrate the effectiveness of our proposed method.