FDTD中近远场变换计算天线方向图的新方法

A Novel NFFF Transformation Algorithm to Calculate the Antenna Pattern in FDTD

针对FDTD中时域近远场外推求方向图的方法运算量太大的缺点,提出一种在时域迭代中对等效面上的场进行傅立叶变换,时域迭代完后得到频域场,再进行频域近远场变换求天线方向图的方法。对该方法的消耗额外内存和消耗额外机时(相对于仅算近场而言)进行分析,数值试验表明,该方法的优点是计算量小而且简单。

The time domain near field to far field(TD-NFFF) transformation consumes too much computational time in the algorithm of FDTD, so we develop a new algorithm: the field on the equivalent face is processed with Fourier Transform during the FDTD’s time iteration, after that making the frequency domain near field to far field(FD-NFFF) transformation to calculate the directivity pattern. The analysis for extra memory and computational time on the new algorithm and the numerical experiment show that the new method has the merits of easily doing and taking little computational time.