一种应用于车地无线通信系统的干扰检测方法  

Interference detecting method for wireless communication system between vehicle and ground

作　　者：李卫军[1] 李竞翔[2] 孙中森[2] 王博 

机构地区：[1]北京市地铁运营有限公司研发中心,北京102208 [2]中国电波传播研究所,山东青岛266107 [3]北京京仪敬业电工科技有限公司,北京100069

出　　处：《电波科学学报》2014年第6期1207-1211,共5页Chinese Journal of Radio Science

摘　　要：城市轨道交通的车地无线通信,正处在一个日益复杂的电磁环境中.文中提出了一种针对城市轨道交通车地无线通信系统的干扰检测算法.该算法采用频域能量检测的方法,通过设置自适应门限对车地无线通信进行干扰的有无检测和频率参数估计.针对经典干扰频率估计方法在低干信比或频谱峰值偏离干扰中心频率,估计误差较大的问题提出了一种改进方法.计算机仿真结果表明:当信号数据速率为5.5 MSPS且干信比达到-7dB以上时,干扰检测概率接近于100%;当信号数据速率为11 MSPS且干信比达到-8dB以上时,干扰检测概率接近于100%.提出的改进频率估计算法,随着干扰信号比的提高,频率估计误差呈现单调减小趋势,在干信比大于10dB时,其性能优于经典算法.Wireless communication between the vehicle and the ground of urban rail transit vehicles is in an increasingly complex electromagnetic environment. Aiming at this problem, this paper puts forward a kind of interference in wireless communication system between urban rail transit and land vehicle detection algorithm. The algorithm uses the method of frequency domain energy detection, by setting the adaptive threshold for wireless communication between the vehicles and the interference with or without detection and frequency estimation of parameters. According to the classical interference frequency estimation method at low interference to signal ratio or peak deviation from the center frequency spectrum interference case, estimation problem of large error and an improved method is proposed. Computer simulation results show that when the sig- nal data rate is 5.5 MSPS and the interference to signal ratio can reach more：than-7 dB, the interference detection probability is close to 100% ; when the signal data rate is 11 MSPS and the interference to signal ratio can reach more than -8 dB, the interfer- ence detection probability is close to 100%. The improved frequency estimation algo- rithm is proposed, along with the increase of interference to signal ratio, frequency esti- mation error decreases monotonically in the present trend of interference to signal ratio is greater than 10dB, and its performance is better than the classical algorithm.

关 键 词：车地无线通信 自适应门限 干扰检测 频率估计 

分 类 号：TN971.1[电子电信—信号与信息处理]