现代电子技术
現代電子技術
현대전자기술
Modern Electronics Technique
2015年
18期
39-41
,共3页
TEM喇叭%阻抗%脉冲峰峰值%超宽带
TEM喇叭%阻抗%脈遲峰峰值%超寬帶
TEM나팔%조항%맥충봉봉치%초관대
TEM horn%impedance%pulse peak value%ultra-wideband
恒阻抗TEM喇叭天线的上、下板之间的间距、板的宽度沿天线轴向呈线性渐变,且喇叭天线的驱动端口、末端端口的宽高比相同.与恒阻抗TEM喇叭天线不同,指数渐变型TEM喇叭天线上下极板之间的间距沿轴向呈指数渐变.研究发现,当指数渐变型TEM喇叭的极板宽度采用不同的渐变形式时,极板宽度线性变化型TEM喇叭天线的驻波比最佳,主射方向远场脉冲峰峰值最大.当天线轴向长度、末端端口高度一定时,天线主射方向远场脉冲峰峰值随着天线末端端口宽度的增大而增大;当末端端口宽度达到一定值时,脉冲峰峰值达到最大值,继续增大末端端口宽度,脉冲峰峰值减小;当天线主射方向远场脉冲峰峰值达到最大值时,天线末端端口阻抗值为215 Ω.
恆阻抗TEM喇叭天線的上、下闆之間的間距、闆的寬度沿天線軸嚮呈線性漸變,且喇叭天線的驅動耑口、末耑耑口的寬高比相同.與恆阻抗TEM喇叭天線不同,指數漸變型TEM喇叭天線上下極闆之間的間距沿軸嚮呈指數漸變.研究髮現,噹指數漸變型TEM喇叭的極闆寬度採用不同的漸變形式時,極闆寬度線性變化型TEM喇叭天線的駐波比最佳,主射方嚮遠場脈遲峰峰值最大.噹天線軸嚮長度、末耑耑口高度一定時,天線主射方嚮遠場脈遲峰峰值隨著天線末耑耑口寬度的增大而增大;噹末耑耑口寬度達到一定值時,脈遲峰峰值達到最大值,繼續增大末耑耑口寬度,脈遲峰峰值減小;噹天線主射方嚮遠場脈遲峰峰值達到最大值時,天線末耑耑口阻抗值為215 Ω.
항조항TEM나팔천선적상、하판지간적간거、판적관도연천선축향정선성점변,차나팔천선적구동단구、말단단구적관고비상동.여항조항TEM나팔천선불동,지수점변형TEM나팔천선상하겁판지간적간거연축향정지수점변.연구발현,당지수점변형TEM나팔적겁판관도채용불동적점변형식시,겁판관도선성변화형TEM나팔천선적주파비최가,주사방향원장맥충봉봉치최대.당천선축향장도、말단단구고도일정시,천선주사방향원장맥충봉봉치수착천선말단단구관도적증대이증대;당말단단구관도체도일정치시,맥충봉봉치체도최대치,계속증대말단단구관도,맥충봉봉치감소;당천선주사방향원장맥충봉봉치체도최대치시,천선말단단구조항치위215 Ω.
The separation distance between upper and lower plates,and the width of plates of TEM horn antenna with con-stant impedance changes linearly along the axial direction,while the wide ratio of driver port and terminal port is the same. Dif-ferent from constant impedance TEM horn antenna,the plate distance between upper and lower plates of the exponential tapered TEM horn antenna is exponentially graded along the axial direction. It is found in the research that when the different plate width gradient forms of exponential tapered TEM horn antenna are adopted,the best standing wave ratio and its VPP(peak to peak value of the far-field pulse in the axial direction)are the best. If the antenna length along the axial direction and the height of end port is a constant value,the TEM horn antenna''''VPP changes with the width of end port. When the end port impedance is 215 Ω,the VPP is the maximum.