宽带卫星IP通信网络中数字调制解调技术研究  

Research on digital modulation and demodulation technology in broadband satelliteIP communication network

作　　者：蒋锐 舒康宁 杨国彬 徐非 余珂 JIANG Rui;SHU Kangning;YANG Guobin;XU Fei;YU Ke(Yunnan Meteorological Information Center,Kunming 650034,China)

机构地区：[1]云南省气象信息中心,云南昆明650034

出　　处：《电子设计工程》2024年第2期187-190,195,共5页Electronic Design Engineering

摘　　要：针对宽带卫星网络之间互连的协议(Internet Protocol,IP)通信网络解调过程中受到非线性通信信道影响,出现信道失真,导致通信信道误码率高的问题,提出宽带卫星IP通信网络中数字调制解调技术。利用I/Q偏压进行数字式调制,避免正交型时引起的信道间干扰。通过星座图调制信号,使其满足恒包络特性,获取星座图向量。求解调制码元中各位元的对数似然比,利用基于通道特征的解调方法,解调振幅畸变和相位畸变的星座图。根据获取的星座图星座点坐标,构建通信信道参数估计模型。使用最小二乘法估计信道参数向量修正的星座图并进行解调,使用四相移相键控解调差分检测方式修正信号幅频,达到更平稳的通信效果。由解调性能实验分析结果可知,该技术能够使解调曲线趋于一条直线,达到频域均衡的目的,且误码率最小为10-5 B,可实现通信网络的高效准确解调。The digital modulation and demodulation technology in broadband satellite IP communication network is proposed to solve the problem of high bit error rate due to channel distortion caused by nonlinear communication channels in the demodulation process of broadband satellite IP communication network.I/Q bias voltage is used for digital modulation to avoid inter channel interference caused by quadrature.By modulating the signal with constancy envelope,the constellation vector is obtained.Solve the log likelihood ratio of each bit in the modulation symbol,and demodulate the constellation with amplitude distortion and phase distortion using the demodulation method based on channel characteristics.According to the obtained constellation coordinates,the communication channel parameter estimation model is constructed.The least square method is used to estimate the constellation of channel parameter vector correction and demodulate.The amplitude frequency of the signal is corrected by using the differential detection method of four phase shift keying demodulation to achieve a more stable communication effect.According to the analysis results of demodulation performance experiment,this technology can make the demodulation curve tend to a straight line,achieve the purpose of frequency domain equalization,and the minimum bit error rate is 10-5 B,which can achieve efficient and accurate demodulation of the communication network.

关 键 词：宽带卫星 IP通信网络 数字调制解调 四相移相键控 

分 类 号：TN927[电子电信—通信与信息系统]