脉冲收发天线辐射特性的矩量法分析

研究了如何采用矩量法（MoM）和快速傅里叶变换（FFT），分析脉冲收发天线的时域辐射特性，同时探讨信号的带宽、天线的仰角和天线的长度对天线辐射性能的影响。文中以窄脉冲电压信号馈电的偶极子天线为例，详细分析了脉冲收发天线辐射特性参数计算公式的建立，以及采用矩量法和FFT获得这些参数的计算方法。计算结果表明，天线远区场与馈电电压波形极为相似，其幅度也随着信号带宽和天线长度的变化而变化。天线仰角的变化，仅仅对远区场的幅度产生影响，而对其大致的形状以及峰值出现的时刻几乎没有影响。

Method-of-Moments Analysis of Radiation Characteristic of an Antenna for an Impulse Signal

The time-domain radiation characteristic of an antenna for an impulse signal is analyzed using Method-of-Moments(MoM) and Fast Fourier Transformation(FFT) in this paper.In addition,the effects of signal bandwidth,elevation angle of the antenna,and the antenna length are also discussed.The dipole fed by short pulse voltage signal is taken as an example to illustrate that the detailed derivation of the radiation characteristic formula of impulse antenna,and that the computation method of obtaining the parameter with MoM and FFT.The simulating results show that the far field is quite similar to the driving voltage source and the amplitude of the far-field changes according to the signal bandwidth and the length of the antenna.In addition,the variation of elevation angle will only impact on the amplitude of the radiated waveforms and have little effect on the shape of the far-field and the time at which the pulse peaks.