基于导频辅助的高动态信号捕获技术研究

Research on high dynamic signal capture technology based on guide frequency assistance

摘要:

针对卫星-高动态终端相对移动过程中速度和加速度高，造成多普勒频移跨度大、变化率高的问题，提出了一种导频辅助的高动态突发信号捕获技术；对卫星-终端通信链路的信道特性进行了研究，该技术采取基于FFT算法、频偏预补偿的对抗措施，构建了链路发送端和接收端的多普勒频移补偿信道模型；并设计了多帧头同步、导频辅助的新型架构，有效降低了低信噪比下帧传输的错误率；仿真结果表明：该算法达到1e-5误码率指标时接收灵敏度提高了3dB左右，满足高动态终端接入卫星移动通信系统的需求。

Abstract:

Aiming at the problems of high speed and acceleration during the relative movement of satellite and high dynamic terminal, which cause large Doppler frequency shift span and high variation rate, a pilot-assisted high dynamic burst signal capture technique is proposed; the study investigates the channel characteristics of the satellite-terminal communication link, and the technology adopts countermeasures based on the FFT algorithm and frequency bias pre-compensation, which constructs the Doppler frequency shift compensated channel models for the transmitter and receiver；and designs a new architecture of multi-frame header synchronization and pilot-assisted architecture, which effectively reduces the error rate of the frame transmission under the low signal-to-noise ratio; the simulation results show that: the algorithm achieves a 1e-5 BER index with an improvement in the reception sensitivity of approximately 3 dB, which meets the demand of high dynamic terminal access to the satellite mobile communication system.