无人机集群组网高精度测距技术研究

Study on highly precise ranging method in UAV cluster network system

针对无人机组网系统机间测距精度受限于时域采样周期时延估计的问题,本文提出一种联合正交频分复用(OFDM)前导序列和导频序列进行高精度测距估计的方法,利用最大似然估计和双向测距法将参与计算的序列测距估计结果按比例进行加权平均。同时,仿真分析了联合测距估计方法性能。结果表明:联合估计方法的前导与导频序列差分自相关间隔长度取典型值时测距精度能达到0.1 m以下,可在较低信噪比下实现厘米级测距精度,提升了集群组网测距的稳定性。

Aiming at the problem that the accuracy of ranging within UAV cluster networking system is limited by the time delay estimation of sampling period in time domain,this paper proposes a method of high precision ranging estimation by combining OFDM preamble sequence and pilot sequence.The maximum likelihood estimation and two-way ranging method are used to carry out weighted average of the estimated results of the sequence ranging.At the same time,the performance of joint ranging estimation method is analyzed by simulation.The simulation results show that the ranging accuracy of the joint estimation method can reach below 0.1 m when the typical values of the difference autocorrelation interval length of the preamble and pilot sequences are taken,and the centimeter-level ranging accuracy can be achieved at a low signal-to-noise ratio,which improves the stability of the ranging of the UAV cluster network.