基于信号特性的宽带航空数据链信号来向估计方法  

Signal Direction Estimation Method for Wideband Aeronautical Data Link System Based on Signal Characteristics

作　　者：王磊[1] 孙海霞 刘明莉 李冬霞[1] 刘海涛[1] WANG Lei;SUN Haixia;LIU Mingli;LI Dongxia;LIU Haitao(Tianjin Key Laboratory for Advanced Signal Processing,Civil Aviation University of China,Tianjin 300300,China)

机构地区：[1]中国民航大学天津市智能信号与图像处理重点实验室,天津300300

出　　处：《信号处理》2022年第7期1458-1466,共9页Journal of Signal Processing

基　　金：国家自然科学基金(U1733120);中央高校基本科研业务费项目(312201905)。

摘　　要：L频段数字航空通信系统(L-DACS)是未来面向航路阶段的空地数据链路,其工作频段计划部署在航空无线电导航频段,与民航测距机(DME)的频谱有部分重叠,容易受到大功率DME信号的干扰,为了在抑制干扰的同时能充分利用阵列天线的增益,有必要提前估计出L-DACS信号的波达方向。针对航空信道特点,并考虑到机载平台高速运动导致的多普勒频移影响,将L-DACS信号建模为渐进准循环平稳信号,提出了基于渐进准循环平稳特征的L-DACS系统信号来向估计方法。仿真结果表明,该方法能够在机载平台高速运动且受DME信号干扰的场景下估计出期望信号的来向,具有较高的估计准确度和良好的低信噪比适应能力。L-band digital aeronautical communication system(L-DACS)is the future air-ground data link for the route stage.The working frequency band of L-DACS is planned to be deployed in the aviation radio navigation band,and the spectrum of L-DACS is partially overlapped with the spectrum of distance measuring equipment(DME),which is vulnerable to the interference of high power DME signal.In order to make full use of the gain of the array antenna while suppressing the interference,it is necessary to estimate the direction of arrival of the L-DACS signal in advance.According to the characteristics of aviation channel and considering the Doppler frequency shift caused by the high-speed motion of airborne platform,the L-DACS signal is modeled as a wide-sense generalized almost-cyclostationary signal(GACS),and the direction estimation method of L-DACS signal based on the wide-sense generalized almost-cyclostationary feature is proposed.Simulation results show that this method can estimate the direction of OFDM signal in the scene of high-speed movement of airborne platform and interference of DME signal,and has high estimation accuracy and good adaptability to low signal-to-noise ratio.

关 键 词：L频段数字航空通信系统 测距仪 多普勒频移 循环平稳特性 波达方向估计 

分 类 号：TN957.51[电子电信—信号与信息处理]