测距仪信号功率谱及邻道泄露功率  

Power spectrum of DME signal and its leakage power in adjacent channel

作　　者：刘海涛[1] 刘莉[1] 王磊[1] 李冬霞[1] LIU Haitao;LIU Li;WANG Lei;LI Dongxia(Intelligent Signal and Image Processing Key Lab of Tianjin,CAUC,Tianjin 300300,China)

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

出　　处：《中国民航大学学报》2024年第1期10-15,共6页Journal of Civil Aviation University of China

基　　金：国家自然科学基金项目(U2233216)。

摘　　要：为了解决宽带航空数据链频率资源匮乏的问题,L频段数字航空通信系统(L-DACS,L-band digital aeronautical communications system)将以内嵌的方式部署在航空无线电导航L频段测距仪(DME,distance measure equipment)波道间,因此,不可避免产生测距仪信号干扰L-DACS系统接收机的问题。为了定量描述DME/N(distance measure equipment/normal)与DME/P(distance measure equipment/precision)信号带外泄露对LDACS系统接收机的影响,首先建立了DME/N与DME/P信号数学模型,然后理论推导出DME/N与DME/P信号的功率谱密度表达式,以此为基础研究了DME/N与DME/P信号带外泄露对邻道部署的L-DACS系统接收机的影响,最后通过计算机仿真验证了理论分析结果的正确性。研究表明:DME信号带外泄露对L-DACS系统的影响主要表现在第一邻道,DME/P信号在第一邻道内泄露功率比DME/N信号泄露功率高约10 dB。To solve the problem of spectrum resource scarcity in aeronautical data link,L-band digital aeronautical communications system(L-DACS)will be deployed as an inlay system in the spectral gaps between channels of the distance measuring equipment(DME).Therefore,it′s unavoidable that the DME signal has a severe influence on the performance of L-DACS system receiver.To analyze the influence of out-of-band leakage of DME/N(distance measure equipment/normal)and DME/P(distance measure equipment/precision)signal on L-DACS system receiver,the mathematical models of DME/N and DME/P signal are established,firstly.Then,the expressions of power spectral density of DME/N and DME/P signal are theoretically derived.Based on these expressions,the effect of out-of-band leakage of DME/N and DME/P signal on L-DACS receiver,which is deployed in adjacent channel,are researched.Finally,the correctness of the theoretical analysis results is verified through computer simulation.The results show that the impact of out-of-band leakage of DME signal on L-DACS system is mainly manifested in the first adjacent channel,and the leakage power of DME/P signal in the first adjacent channel is 10 dB higher than that of DME/N signal.

关 键 词：L频段数字航空通信系统 测距仪 邻道干扰 功率谱 带外泄露功率 

分 类 号：V243.1[航空宇航科学与技术—飞行器设计] TN929.5[电子电信—通信与信息系统]