Using sources of opportunity to estimate digital compensation for receiver mismatch in HF arrays

The spatial processing performance of adaptive sensor arrays is often limited by the non-identical frequency responses of the receivers in the array over the passband of interest, This paper addresses the problem of estimating digital compensation for mismatches between receiver passbands in high frequency (HF) antenna arrays using interference sources of opportunity. A mathematical model of multipath HF interference is developed and an adaptive algorithm based on this model is proposed to estimate the receiver frequency response corrections. The effectiveness of the proposed algorithm is demonstrated and compared against a commonly used adaptive technique and a highly accurate calibration system using experimental data collected by the receiving antenna array of the Jindalee over-the-horizon (OTH) radar