基于Mach-Zehnder干涉仪的编队卫星光通信多址接入性能研究

Performance Research of Multiple Access in Optical Communication of Satellite Formation Flying Based on Mach-Zehnder Interferometer

随着小卫星技术的蓬勃发展和空间激光通信的成熟,编队卫星激光通信以其机动,灵活,容量大,抗干扰能力强和低成本等优点而成为国际航空航天,特别是军事领域的研究热点。提出了编队卫星群对地通信模型,系统利用Mach-Zehnder干涉仪两臂时延差分别在发送端和接收端进行编解码。建立了光场干扰数学模型,以相互独立光场为基础,研究了在大气弱抖动条件下接收光场和干扰噪声,推导出了系统的信噪比(SNR)和误码率(BER)公式。最后,通过仿真计算对这一模型进行验证和性能分析,结果表明该模型在卫星个数较少时具有一定的工程应用价值。

With the development of satellite formation flying in space and maturing of optical space communication, laser communication of satellite formation flying becomes the focus in the field of international aeronautics and astronautics, especially in that of military, because of its advantages of mobility, flexibility, high capacity, anti-interference and lower cost. The multiple access communicating model from satellites to the control center was proposed, which makes use of delay difference between two arms of Mach-Zehnder interferometer to encode and decode at the end of transmitter and receiver respectively. Math model of optics field interference was built, by which the received optical signal and interference noise in weak atmosphere turbulence were analyzed based on independent optic fields, the formulations of signal noise ratio （SNR） and bit error rate （BER） were deduced. The model was validated and its performance was analyzed by numerical simulation. The simulation results show that the proposed model has the engineering application value on condition of a few satellites in Satellite Formation Flying.