Impact of PRF design on GMTI performance of MIMO-SAR for hypersonic platform with curved trajectory

Abstract

Compared with the conventional single-channel sampling or azimuth multichannel sampling of SAR system, the multiple-input multiple-output (MIMO) sampling has the potential to realise the high-resolution wide swath (HRWS) imaging and the ground moving target indication (GMTI) simultaneously. As a key parameter in the design of SAR system, the pulse repetition frequency (PRF) has important impacts on the performances of HRWS and GMTI. From this perspective, the impacts of PRF design on GMTI performance of MIMO-SAR for hypersonic platform with curved trajectory have been analysed here. Specifically, the steering vectors of the ambiguous clutter and moving target are derived first under the curved trajectory model. Furthermore, according to MIMO-SAR system parameters, the optimum PRF design is simulated from the aspects of the blind velocity, the spatial ambiguity, and the detection probability. Finally, the real clutter data are further used to verify the effectiveness of PRF design on GMTI performance optimisation.

Keywords

• synthetic aperture radar
• radar signal processing
• spaceborne radar
• radar antennas
• geophysical signal processing
• radar resolution
• radar imaging
• radar clutter
• pulse repetition frequency
• important impacts
• HRWS
• hypersonic platform
• curved trajectory model
• MIMO-SAR system parameters
• optimum PRF design
• GMTI performance optimisation
• single-channel sampling
• azimuth multichannel sampling
• multiple-input multiple-output sampling
• high-resolution wide swath imaging
• ground moving target
• key parameter