Element-space spatially waveform diverse FMCW radar distributed on naval formation

Large antenna arrays are very costly and, in particular in the case of shipborne platforms, array dimensions are limited. In order to overcome these constraints for the naval application of a High-Frequency Surface Wave Radar (HF SWR) we propose to make use of multiple ships sailing together within a naval formation. This distributed array will be sparse and we apply the concept of effective aperture to avoid gratinglobes. In order to satisfy both, fast azimuth scan within the coherent integration time and dynamic transmit array beamforming-which is essential for the concept of effective aperture-we further propose to apply of the concept of transmit beamsteering on receive using time shifted Frequency Modulated Continuous Wave (FMCW) signals for the individual elements of the transmit array.