一种S波段基于热致振动引起无源互调的初步机理分析
«上一篇
文章快速检索     高级检索
下一篇»
  应用科技  2018, Vol. 45 Issue (3): 19-22  DOI: 10.11991/yykj.201701014
0

引用本文  

潘松松, 吴秉琪, 何瑜, 等. 一种S波段基于热致振动引起无源互调的初步机理分析[J]. 应用科技, 2018, 45(3), 19-22. DOI: 10.11991/yykj.201701014.
PAN Songsong, WU Bingqi, HE Yu, et al. A preliminary mechanical analysis on passive intermodulation based on thermal induced vibration at S-band[J]. Applied Science and Technology, 2018, 45(3), 19-22. DOI: 10.11991/yykj.201701014.

基金项目

国家自然科学基金项目(61271074)

通信作者

刘长军,E-mail:cjliu@scu.edu.cn

作者简介

潘松松(1993−),男,硕士研究生;
刘长军(1973−),男,教授

文章历史

收稿日期:2017-01-24
网络出版日期:2017-05-04
一种S波段基于热致振动引起无源互调的初步机理分析
潘松松, 吴秉琪, 何瑜, 刘长军    
四川大学 电子信息学院,四川 成都 610064
摘要:针对S波段通信系统中的无源互调(PIM)干扰问题,提出了一种基于热致振动的无源互调新机理。在双频微波输入条件下,从拍现象中温度波动出发,通过热致振动中的阻抗变化关系,建立了统一的传输线非线性方程,然后以波导为对象进行了多物理场仿真分析和实验验证。设计并加工了3种不同窄边厚度的BJ-22型波导,利用大功率无源互调测量系统,在47~53 dBm功率范围内测试波导9阶PIM功率。结果表明,相同大功率输入条件下,波导壁越薄,波导PIM越强,显示热致振动会引起PIM并受振动程度的影响。
关键词无源互调    热致振动    多物理场仿真    波导    拍现象    非线性传输线方程    电热耦合    大功率    
A preliminary mechanical analysis on passive intermodulation based on thermal induced vibration at S-band
PAN Songsong, WU Bingqi, HE Yu, LIU Changjun    
School of Electronics and Information Engineering, Sichuan University, Chengdu 610064, China
Abstract: A new mechanism of passive intermodulation (PIM) based on thermally induced vibration is proposed to deal with the problem caused by PIM in communication systems at S-band. In the dual-frequency microwave signals input conditions, starting with the temperature fluctuation of beat phenomenon, a unified nonlinear equation of transmission line was established by using the impedance changing equation in thermally induced vibration, then waveguide was selected as the object to do multi-physics simulation analysis and experimental verification. Three BJ-22 microwave waveguides with different narrow wall thicknesses were designed and fabricated. The waveguides’ 9th order PIM with power ranging from 47 dBm to 53 dBm was tested by using the high power PIM measurement system. The results show that the waveguide with thinner narrow wall produced higher PIM power compared to that with thicker narrow wall under the same conditions. It indicates that the thermal induced vibration of the transmission line will lead to PIM effects and it is affected by the degree of vibration.
Key words: passive intermodulation    thermally induced vibration    multi-physics simulation    waveguide    beat phenomenon    nonlinear transmission line equation    electro-thermal coupling    high power    

无源互调(passive intermodulation,PIM)是在卫星、雷达等通信系统中常见的一类干扰信号,当复数个载波信号通过无源器件时,由于器件固有的部分弱非线性特质,其输出信号将包含各载波混频的产物,并恶化接收系统的通信质量。随着通信系统的可利用频谱越来越窄,功率容量日渐增大,PIM效应也显著增强,使得其成为了限制系统发展的主要瓶颈之一[1-3]。引发PIM的根源种类繁多,大致可归类为两种:接触非线性和材料非线性[4]。接触非线性是指具有非线性电流和电压特性的电接触,比如金属焊接和裂缝、金属-氧化物-金属连接等[5];材料非线性是指具有固有非线性电特性的材料,如铁磁体、等离子体、热敏电阻等。从多物理场的角度来说,器件由于温度变化而出现的众多非线性效应也是产生PIM的潜在因素。文献[6]从电热耦合效应的角度研究了阻性器件的PIM问题,文献[7]提出了基于热电子发射效应的波导结非线性无