光学波束形成网络相对于传统电学波束形成网络具有带宽大、传输损耗小、抗电磁干扰等特性。国内在多通道射频信号输入情况下,基于色散光纤体制的光学波束形成网络的插损变化规律研究较少。假设光子探测器达到饱和阈值的前提下,分别计算了单通道微波光子链路与双通道光学波束形成网络的插损。推导得到,随着输入射频通道数的成倍增加,采用色散光纤体制的光学波束形成网络的插损也成倍增加。搭建了实验系统,发现当输入射频通道数为2、4、8、16时,对应插损分别为-26.0 dB、-30.8 dB、-34.3 dB、-46.0 dB。

Optical beam forming network has the characteristics of large bandwidth, low transmission loss, and anti-electromagnetic interference, compared with the traditional electrical beam forming network. In the case of multi-channel radio frequency signal input, the law of insertion loss of optical beam forming networks based on the dispersion fiber system is less studied. Assuming that the photon detector reaches the saturation threshold, the insertion losses of the single-channel microwave photon link and the dual-channel optical beam forming network are calculated. It is deduced that as the number of input radio frequency channels increases by multiple folds, the insertion loss of the optical beam forming network using a dispersion fiber also increases in an alike manner. A test system was set up, and verification was carried out. When the number of input radio frequency channels was 2, 4, 8, and 16, the corresponding insertion loss was -26.0 dB, -30.8 dB, -34.3 dB, and -46.0 dB, respectively.