太赫兹频段星地通信信道建模与仿真

Modeling and simulation of satellite-ground communication channel in terahertz frequency band

太赫兹频段作为至今尚未被完全开发的超高通信频段,具有超大带宽等优点,将其应用于第五代(the 5th Generation,5G)、后五代(Beyond 5G,B5G)移动通信系统,除实现更高速率传输外,还可实现地面移动网络与卫星网络频谱资源的共享,有利于推动新一代空天地一体化通信网络建设.文章提出了一种适用于星地通信系统的太赫兹信道建模与仿真方法,分析了自由空间损耗、分子吸收损耗、云雾衰减、雨衰减及多普勒频移等太赫兹信道的影响因素,构建了星地太赫兹通信信道建模流程,并给出了分步骤信道参数的生成方法.通过数值仿真,对不同天气状况下传输距离和频率对传输信号的影响进行了分析,并基于所生成的信道响应对误码率进行评估,从而验证了所提出模型和方法的可用性.所提建模方法能够提供不同传输条件下的动态太赫兹信道响应数据,从而为今后太赫兹频段无线通信系统的设计与开发提供评估与测试依据.

Terahertz（THz） band, as the ultra-high communication band which has not yet been fully developed, has large bandwidth and other advantages.Its application in the 5th generation （5G） and Beyond 5G （B5G） systems can achieve higher transmission speed and realize the sharing of terrestrial mobile networks and satellite network spectrum resources, which is conducive to promoting the construction of a new generation of air and space integrated communication network.In this paper,a THz channel modeling and simulation schemeis proposed for the satellite-ground communication system. The factors which have impact on the THz channels are analyzed, including free space loss, molecular absorption loss, cloud attenuation, rain attenuation, and Doppler frequency shift. The modeling procedureis built for the satellite-ground THz communication channel and the method of generating channel parameters are presented in steps. The influence of the transmission distance and frequency on the transmission signal in different weather conditions is analyzed by numerical simulations. The bit error rate are evaluated based on the generated channel responses.Thus, the feasibility of the proposed model and method has been verified. The proposed modeling scheme can provide dynamic THz channel [JP2]response data under different transmission conditions.It can provide basis for the design and development of the future THz band wireless communication systems.