摘要
对于近地轨道飞行器与卫星之间的通信链路,信号收发两端之间的相对运动导致载波存在高动态的多普勒频偏。另外,信号的远距离传输使得信号很微弱,这就极大地降低了信噪比。为了解决低信噪比和高动态环境下的多普勒频偏估计问题,提出一种多累积周期估计方法,提高多普勒频偏检测概率。该方法利用多个信号累积周期来缩小下一个累积周期内谱峰检测的频率区间,进而提高多普勒估计性能。理论分析和仿真结果表明,与现有方法相比,提出的多累积周期估计方法不仅可以提高检测概率而且可以减小估计误差。
For the communication link between the low earth orbit(LEO) aircraft and satellite,the relative movement between the signal receiving and transmitting ends may cause the high-dynamic Doppler-shift of the carrier.The long-distance transmission of signal makes the signal weak,and reduces the signal-to-noise ratio(SNR) greatly.In order to improve the SNR and accuracy of the Doppler-shift estimation in high-dynamic environment,an estimation method based on multiple accumulation cycles is proposed to improve the detection probability of the Doppler-shift.The multiple accumulation cycles of the signal are used in the method to shorten the frequency section of spectrum-peak detection in the next accumulation cycle,and improve the performance of Doppler estimation.The theoretical analysis and simulation results show that,in comparison with the available methods,the proposed method can improve the detection probability,and reduce the estimation error.
出处
《现代电子技术》
北大核心
2018年第3期36-40,共5页
Modern Electronics Technique
基金
国家自然科学基金(71161006)~~
