Abstract
Multiple-input multiple-output (MIMO) synthetic aperture radar (SAR) has received significant attention to radar communities recently. However, only few attempts on compressed sensing based MIMO SAR have been reported. This paper presents a novel scheme for wide-swath and high-resolution SAR based on MIMO ultra-wideband (UWB) orthogonal frequency division multiplexing (OFDM) system using compressed sensing (CS) technique. The swath is increased based on a new approach for orthogonal pulse-shaping and MIMO wide-swath stripmap SAR topology. The resolution is improved by using UWB-OFDM waveforms and the computational complexity is reduced by adopting the CS approach. CS based sparse imaging method is developed to deal with MIMO UWB-OFDM SAR using orthogonal matching pursuit (OMP) algorithm. Super-resolution property and image reconstruction ability are demonstrated using simulated data. Simulation results are provided to demonstrate the performance improvement of the proposed methods. Results show that the presented CS method outperforms the conventional matched filter (MF) based SAR imaging algorithm even though small amount of samples from SAR echo is used. Simulation results of conventional MF based SAR are also provided for fair comparisons. Performance is further enhanced using image fusion techniques to benefit from the potentials of multi-sensor imagery such as noise level reduction.