GLRT detection of broadband signals using an array of electromagnetic vector sensors

The problem of detecting a point-source, broadband signal originating from a known direction is addressed using an array of vector sensors. The signal is accompanied by zero-mean noise with an unknown covariance. The broadband detector is constructed by transforming each narrowband snapshot in the frequency domain into a rank one subspace. This reduces the broadband problem into a generalization of the narrowband detection problem and yields results formerly associated only with the narrowband detection problem. Consideration is also given to a subspace extension, called a `sparse subspace´, that exploits the symmetry inherent in the received electromagnetic field