气象
氣象
기상
METEOROLOGICAL MONTHLY
2015年
8期
1023-1027
,共5页
李喆%何平%潘新民%高玉春%吴蕾
李喆%何平%潘新民%高玉春%吳蕾
리철%하평%반신민%고옥춘%오뢰
风廓线雷达%标定%回波强度%速度%幅相不平衡
風廓線雷達%標定%迴波彊度%速度%幅相不平衡
풍곽선뢰체%표정%회파강도%속도%폭상불평형
wind-profiling radar%calibration%echo intensity%velocity%imbalance in amplitude and phase
提文章讨论了风廓线雷达标定系统中的两个问题。首先,在风廓线雷达回波强度标定原理的基础上,依据雷达气象方程,分析了发射功率变化和接收机增益变化对回波强度测量精度的影响,提出了通过实时测量每个脉冲重复周期内发射采样脉冲功率和回波功率在数字中频接收机的输出值,改善回波强度测量精度的方法。其次,在风廓线雷达速度标定原理的基础上,分析了速度标定中因 I/Q 信号的幅度、相位不平衡造成的镜像谱分量,提出了一种基于信号时域统计特性的订正方法,并利用 I/Q 信号数学模型进行了仿真实验,结果表明,该方法可以有效抑制 I/Q 信号幅相不平衡产生的镜像谱分量。
提文章討論瞭風廓線雷達標定繫統中的兩箇問題。首先,在風廓線雷達迴波彊度標定原理的基礎上,依據雷達氣象方程,分析瞭髮射功率變化和接收機增益變化對迴波彊度測量精度的影響,提齣瞭通過實時測量每箇脈遲重複週期內髮射採樣脈遲功率和迴波功率在數字中頻接收機的輸齣值,改善迴波彊度測量精度的方法。其次,在風廓線雷達速度標定原理的基礎上,分析瞭速度標定中因 I/Q 信號的幅度、相位不平衡造成的鏡像譜分量,提齣瞭一種基于信號時域統計特性的訂正方法,併利用 I/Q 信號數學模型進行瞭倣真實驗,結果錶明,該方法可以有效抑製 I/Q 信號幅相不平衡產生的鏡像譜分量。
제문장토론료풍곽선뢰체표정계통중적량개문제。수선,재풍곽선뢰체회파강도표정원리적기출상,의거뢰체기상방정,분석료발사공솔변화화접수궤증익변화대회파강도측량정도적영향,제출료통과실시측량매개맥충중복주기내발사채양맥충공솔화회파공솔재수자중빈접수궤적수출치,개선회파강도측량정도적방법。기차,재풍곽선뢰체속도표정원리적기출상,분석료속도표정중인 I/Q 신호적폭도、상위불평형조성적경상보분량,제출료일충기우신호시역통계특성적정정방법,병이용 I/Q 신호수학모형진행료방진실험,결과표명,해방법가이유효억제 I/Q 신호폭상불평형산생적경상보분량。
This paper discusses two problems on calibration of wind-profiling radar.Firstly,based on the calibration principle of echo intensity,it analyzes the effect of variations in transmitted power and receiver gain on measurement accuracy of echo intensity using weather radar equation.In addition,it puts forward a method to improve measurement accuracy of echo intensity by measuring sampled transmitted pulse and backscattered power at the output of digital receiver during each pulse repetition time.Secondly,according to calibration principle of velocity,it analyzes the image spectral component caused by imbalance in ampli-tude and phase of I/Q signals in velocity calibration.Moreover,it presents a correction method based on statistical characteristics of time domain signals.What’s more,simulation experiment is conducted using mathematic models for I/Q signals.And the result shows that this method can suppress the image spectral component effectively.