双馈电视发射系统中同轴馈管的更换方法  

Replacement Method of Coaxial Cable in Double-fed TV Transmission System

作　　者：周灏[1] 沈斌 王敏海 Zhou Hao;Shen Bin;Wang Minhai(Suzhou Broadcasting System,Jiangsu 215006,China)

机构地区：[1]苏州市广播电视总台,江苏215006

出　　处：《广播与电视技术》2021年第12期97-99,共3页Radio & TV Broadcast Engineering

摘　　要：为提高安全性,电视发射系统中多采用双馈管的形式。本文介绍了苏州台一根馈管故障后,进行更换新馈管的方法。本文通过测试驻波比,得到计算误差小于一个波长的新馈管大概长度;再测量两个馈管的S11参数的相位,并消除其中的相位模糊问题,精确计算出新同轴馈管的长度。最后通过调整新馈管长度,该方法使新旧馈管等长。In order to improve safety,television transmission systems always use double-fed system.This paper provides a method of replacing one coaxial cable of double-fed television transmission system in Suzhou Broadcasting System,when one has some problems.Firstly,approximate length of a new coaxial cable is get by measuring VSWR,and calculation error is less than a wavelength.secondly,precise length of new coaxial cable is get by measuring the phases of S11 parameters for two coaxial cables and solving phase ambiguity problem.At last,by adjusting new cable’s length,this method keeps both new and old coaxial cables in the same length.

关 键 词：双馈电视发射系统 相位模糊 同轴馈管 

分 类 号：TN943[电子电信—信号与信息处理]