The Analysis Of The Noise Performance Of Reflector Antenna Feed Dipole Array

This article mainly analyzes the atmospheric noise of the prime feed paraboloidal reflector antenna.The atmospheric noise of the antenna is mainly affected by two factors:one is the cosmic background radiation and the atmospheric radiation brightness temperature;another is the far field radiation characteristics of the antenna.On this topic,given some expectation of the reflector antenna for feed,Eleven feed is chosen as the front lighting of the rotating parabolic reflecting which has superior properties.Analyzing and calculating the scattering far-field come from the radiation rays through reflector surface,and combining the brightness temperature to estimate the atmospheric noise of antenna under certain conditions.This paper introduces the current research situation of the antenna noise.Then introduced some basic concepts of the antenna,and some properties characteristics of Eleven feed.The following is aimed at the radiation field of rotating parabolic reflector,it is a very important part of this topic,In this part combining with physical optics(PO),geometrical optics(GO)and uniform geometrical theory of diffraction(UTD),to calculate the reflection and diffraction far-field of the reflector antenna by MATLAB program,and for the Fresnel integral which meet in calculating the geometric optical diffraction field,a more accurate calculation method is introduced.Next is another emphasis of this article,this part introduces the definition and the normalization of system noise,and introduces in detail how to compute brightness temperature from the cosmic background radiation and atmospheric radiation.Finally,the paper introduces a novel broadband phase shifter that bandwidth can be achieved 2.65:1,and the insertion loss can be less than 0.6dB,it has great help to the research on circular polarization antenna and the noise of system in future.In this paper,a lot of research relating to the atmospheric brightness temperature and paraboloidal scattering field have been done,which will have important guiding significance in the study of noise about cylindrical parabolic reflector antenna.