天线时域近场测量中的时基及幅度修正技术

 在天线时域近场测量中由于脉冲信号源的时基抖动和幅度变化所带来的误差是测量中最主要的误差,其中尤以时基误差最为严重,它使得方向图畸变到了无法容忍的程度.本文即针对此问题提出了天线时域近场测量中的时基及幅度修正技术.该技术在测量通道之外增加了一个参考通道,通过检测参考通道信号提取出脉冲信号源的时基及幅度变化,进而以此修正测量通道的信号.大量的实际测量表明该技术稳定可靠.通过对比试验发现,使用该技术的时域近场测量结果的精度达到甚至优于频域近场测量结果的精度.

Time Base Correction Technique and Amplitude Correction Technique in Antenna Time Domain Near Field Measurement

In the practice of antenna time domain near field measurement,the biggest errors are introduced by the time base jitter and the amplitude changing of pulse generator.Comparing with the errors caused by amplitude changing,the errors caused by time base jitter are more serious that it can result in unbearable aberrance of measurement pattern.To deal with this problem,the technique of time base correction and amplitude correction is presented in this paper.Besides measuring channel,this technique adds a reference channel in measuring system.Pulse generator’s time base jitter and amplitude changing can be obtained from the reference channel,and be adopted to correct measuring channel’s signal.The practical measuring results have proved this method’s reliability.From comparing experiments,we can find that adopting this technique,the sensitivity of time domain near field measurement is similar to the sensitivity of frequency domain near field measurement,or even better than it.