天线宽频辐射功率的FDTD数值计算

为了实现混响室的仿真电场值与实测值的直接对比，需要计算发射天线的宽频辐射功率．基于坡印廷矢量的面积分，利用时域有限差分算法和快速傅里叶变换，得到了天线宽频辐射功率的快速计算方法．应用该方法对半波偶极子天线和短偶极子天线进行数值仿真，通过仿真值与理论值的比较，验证了该方法的正确性．该方法适用于任何能够用FDTD进行合理建模的电磁设备的辐射功率计算，且一次计算即可得到宽频辐射功率，不仅为混响室仿真结果的归一化打下基础，而且也是分析其他电磁设备宽频辐射特性的可行方法．

On the Numerical Calculation of Antenna＇s Broadband Radiation Power Using FDTD

In order to compare the simulated and measured electric field strength of a reverberation chamber（RC） directly, the broadband radiation power of the transmitting antenna is required. Combining finite-difference time-domain（FDTD） method and fast Fourier transformation （FFT）, an efficient method for the computation of broadband radiation power is proposed based on the ar- ea integral of poynting vector. The method is validated through the comparison between the simu- lation and theoretical results in both cases of half wave dipole and short dipole antennas. This method can be applied to any electromagnetic device that can be depicted by FDTD reasonably and can get the broadband radiation power with only one execution, so it provides a feasible way to an- alyze the radiation characteristics of an electromagnetic device as well as laying the groundwork for the normalization of a RC＇s simulation results.