Comparison of Alamouti Space-Time Coding over FMCW and OFDM Radar Waveforms

Inhalt:
This paper presents a novel approach to enhance the performance of radar systems operating in conjunction with wireless communication systems through the integration of Alamouti space-time coding in frequency modulated continuous wave (FMCW) radar signals. The integration aims to leverage the benefits of both radar and communication systems while addressing the challenges posed by Ricean fading channels. The study emphasizes the trade-off between line-of-sight requirements for radar applications and the advantages of multipath propagation for transmit diversity in wireless communication. The data rate for communication can be modified between a slow symbol rate (one symbol per FMCW chirp) and a fast symbol rate mode (e.g., ten samples per chirp). However, the fast symbol rate degrades range/speed estimation. For comparison, the Alamouti space-time coding is also applied to OFDM radar. This offers the opportunity for much higher data rates but with disadvantages such as high peak-to-average power ratio.