有源非同相多通道接收系统噪声系数测试研究

A Study on Noise Figure Measurements of Active Multi-channel Receive System with Unequal Phase Superposition

传统的噪声系数级联公式仅适用于二端口网络。文中针对非等幅同相叠加的有源多通道接收系统建立了普适的模型,并推导出相应的噪声系数计算公式。在此基础上,对利用二端口测试设备进行多端口系统噪声系数测试的三种方法(增益法、支路法和功分法)的基本原理进行了推导,并在操作复杂度、测试误差等方面进行了对比分析,最后通过仿真实验验证了计算公式和测试方法的准确性,为系统设计阶段的方向图设计和系统链路指标分配提供了理论支持,为系统测试提供了参考。

The traditional noise figure cascading formula is only applicable to two-port network.Focusing on the active multi-channel receive system with unequal amplitude and phase superposition,a universal model is established and corresponding theoretical formula is derived.On this basis,the rationales of three test methods,which employ two-port test equipment to complete the noise figure measurement of multi-port network,has been deduced including the gain method,the branch method and the power divider method.Then comparative analysis is made in terms of operation complexity and test error,and the accuracy of the proposed theoretical formula and test approach is verified by simulation afterwards.This article will provide theoretical support for antenna pattern optimization and system link indicators allocation during system design,also a useful reference for system testing.