低载噪比条件下小型无人机直扩信号的快速粗同步设计

Fast Synchronization Acquisition Algorithm Design for DSSS in Low CNR for Small UAV

在小型侦察型无人机军事应用领域,一般扩频信号的粗同步技术已经难以达到目前低速低动态低载噪比的作战需求,本文针对该应用需求,设计了一种适用于小型侦察无人机直扩信号粗同步的二次FFT与自相关累积结合的方法,在低载噪比条件下相关峰明显,不受残留载波和累积时间影响,底噪干扰小,频偏估计准确,有效保障小型无人机低载噪比军事应用上的信号接收稳定性。

In the military application field of small reconnaissance UAV(Unmanned Aerial Vehicle),general synchronization acquisition technology of DSSS has been difficult to meet the current requirements of low speed and low CNR(Carrier to Noise Ratio).In this paper,a synchronization acquisition algorithm named Double FFT Combine with Autocorrelation for Small UAV is designed and simulated for this application.The correlation peak is obvious,and it is not affected by the residual carrier and accumulation time.The noise interference is small and the frequency estimation is accurate.This effectively promotes the signal reception stability of small UAV in military applications.