A weighted detector for mismatched subspace signals

This paper investigates the problem of detecting a multichannel signal when subspace signal mismatch occurs. A new detector is proposed, which is obtained by weighting two existing detectors, namely, the subspace-based adaptive matched filter and adaptive subspace detector. The proposed weighted detector has flexibility in controlling its capability of rejection mismatched subspace signals. Specifically, its robustness (or selectivity) for mismatched subspace signals improves as the weight value increases (or decreases). Closed-form expressions for the probabilities of detection and false alarm are derived. The theoretical results are confirmed by Monte Carlo simulations.