Performance Bounds for Adaptive Coherence of Sparse Array Radar

To achieve high signal-to-noise ratios (SNR) while maintaining moderate sensor size, an architecture is proposed to combine several independent radar apertures into a coherently functioning unit. The proposed system utilizes several distinct apertures which are to be adaptively cohered based on observed target returns. Two operating modes are presented (in addition to each aperture operating as an independent radar). In the first, a Multiple Input Multiple Output (MIMO) mode, each aperture transmits a distinct waveform. The independent, multi-static returns allow the estimation of several coherence parameters. These estimates may then be used to produce a fully coherent transmit/receive mode, wherein all of the apertures cooperatively transmit a waveform which allows the system to perform as a fully coherent, sparse array.