Doppler ambiguity resolution using random slow-time code division multiple access MIMO radar with sparse signal processing

In this article a novel waveform, Random Slow-Time Code Division Multiple Access (ST-CDMA) for MIMO radar is presented and investigated. ST-CDMA means that the waveforms of the different transmitters are orthogonal per burst, while conventional CDMA implies orthogonal waveforms of the different transmitters per pulse. In particular, the Doppler ambiguity performance of the proposed Random ST-CDMA waveform is compared to that of the well-known Doppler Division Multiple Access (DDMA) waveform, which is a specific type of ST-CDMA. Both in combination with conventional processing (based on matched filters) and with Sparse Signal Processing (SSP) the DDMA waveform yields a reduction in unambiguous Doppler range as compared to other MIMO waveforms, such as CDMA. Instead, the Random ST-CDMA waveform together with SSP yields no reduction in unambiguous Doppler Range and improved side lobe suppression.