TDS-OFDM雷达通信共享信号波形设计

在使用正交频分复用(Orthogonal Frequency Division Multiplexing, OFDM)信号的雷达通信一体化系统中,循环前缀(Cyclic Prefix, CP)和导频的存在,使得共享信号在自相关运算中出现较高的副瓣电平,严重影响雷达检测性能。针对这个问题,提出一种新的基于时域同步OFDM(Time Domain Synchronization OFDM, TDS-OFDM)的共享信号形式,该信号利用训练序列填充保护间隔,同时完成同步与信道估计,从而避免了CP副瓣和导频副瓣的出现。首先分析TDS-OFDM共享信号的模糊函数,然后通过训练序列的优化设计,有效降低TDS-OFDM信号的距离峰值副瓣,同时保持训练序列自身良好的自相关性能。理论分析与仿真表明,相对于CP-OFDM,TDS-OFDM共享信号更加适用于雷达通信一体化系统。

Waveform design of integrated radar and communication signals based on TDS-OFDM

In the IRCS(integrated radar and communication system), which uses OFDM(orthogonal frequency division multiplexing) signals, the CP(cyclic prefix) and pilots can cause the problem of high peak to side lobe level in autocorrelation operation, which deteriorates the radar detection performance seriously. To solve this problem, a new RadCom signal based on TDS-OFDM(time domain synchronization OFDM) was proposed. The TDS-OFDM adopts TS(training sequence) for guard interval, as well as synchronization and channel estimation, so that the CP and pilots can be avoided. First, the ambiguity function of TDS-OFDM RadCom signal was analyzed. And then, TS was optimized to suppress the range side lobe of TDS-OFDM signal and maintain the autocorrelation properties of TS simultaneously. Theoretical derivation and simulation results show that TDS-OFDM signals are more suitable than CP-OFDM signals for IRCS.