A system and method are provided for estimating bearing of a target based on RF signals received by an array of antenna elements. The system comprises first and second input channels that are configured to receive analog signals that correspond to first and second antenna elements. The system also includes an analog to digital converter module for converting each of the analog signals to digital data samples and outputting separate streams of digital data samples corresponding to each of the first and second antenna elements as first and second data streams. An in-phase and quadrature detector module includes a phase shift module for shifting each of the first and second data streams by a predetermined amount of time to form first and second phase shifted data streams. A surveillance module determines a bearing of the target based on in-phase and quadrature data.