A self-correcting loop for joint estimation-calibration in adaptive radar

It is well known that pointing and random angle errors degrade the performance of adaptive radar quickly. A joint adaptive estimation-calibration (JEC) algorithm is proposed to provide on-line look direction corrections and array calibration. The new algorithm is presented in the context of a generalized sidelobe canceler (GSC). The proposed algorithm uses the array output to generate a control signal for steering vector corrections, which in turn yield higher signal-to-noise and interference ratio (SNIR) at the array output. A Doppler technique is used to provide cleaner reference of target signal, which results in better correction of the steering vector. A simple case is investigated to explain how the scheme works and a steady state condition analysis is provided. For an 8-element antenna array, the new algorithm is demonstrated by simulations, which show that the output SNIR is improved by the correction of pointing and random angle errors