A New Method of Integrated Radar-Communication System Waveform Design and Signal Processing Based on OFDM Block Subcarrier Allocation

In the context of the Internet of Vehicles (IoV) and sixth-generation (6G) wireless communication, wireless radar and communication (RadCom) systems face the dual challenges of improving spectrum utilization efficiency and lowering interference levels. The use of orthogonal frequency division multiplexing (OFDM) signals in a shared waveform system has the potential to mitigate mutual interference between communication and radar while also meeting the need for improved range resolution. Some researchers have proposed using the odd and even carriers of OFDM signals to modulate radar and communication functions, intending to achieve integration. Nevertheless, this methodology presents several concerns, such as the potential for interference between radar carriers and communication carriers and the negative impact caused by the cyclic prefix (CP) on radar performance. This study presents a new method that leverages OFDM and block subcarrier allocation techniques to enhance the integration of radar and communication system performance. The primary objective is to mitigate interference by consolidating radar and communication subcarriers while minimizing the detrimental effects of CP on radar performance by utilizing zero padding (ZP) as a replacement for CP. Furthermore, this method reduces pilot tone costs by utilizing radar data to estimate Doppler frequency offsets. It can dynamically adjust the number of radar and communication subcarriers to accommodate evolving performance demands. Simulation results indicate that in the presence of residual frequency offset, this solution enhances communication performance while slightly degrading radar performance.