中文摘要：

应用时域有限差分（FDTD）法对混响室进行时域建模仿真,结合快速Fourier变换（FFT）可得到混响室的宽频响应,但由于混响室本质上属于高品质因数（Q）的谐振腔体,仿真时往往遇到计算时间冗长的问题。为克服该问题,基于腔体储能衰减规律,推导出了混响室内电场强度衰减与Q值的关系式,实现了混响室损耗后处理方法。该方法可预估混响室时域仿真所需的时间步数,由一次无损耗仿真结果,可实现混响室在不同损耗程度下的数值模型快速计算。对实际混响室进行数值建模,模型计算结果与实测数据一致性较好,验证了提出方法的正确性。仿真发现：混响室的场均匀性随工作频率增大而变好,而当损耗程度大于实际情况时,场均匀性会出现一定恶化。该处理方法为混响室和其他电磁腔体的时域3维全波快速仿真提供了新思路,具有参考价值。

英文摘要：

It takes awful computation time to obtain a complete wideband response of a reverberation chamber（RC） through the finite-difference time-domain（FDTD） simulation combined with FFT to signals in time domain because of the RC’s high quality factor（Q）.To overcome this disadvantage,using the energy attenuation law of a cavity,we derived an attenuation formula for electric field strength and Q,and achieved a method of the loss processing in post stage.The method could estimate the required iterations in a time-domain simulation of RC.Moreover,combining with a one-time lossless simulation of RC,the method could realize the accelerated computation of RC numerical model under different loss levels.The method is validated by the acceptable agreement of measured data and the simulation result of a RC.According to the simulation results,the field uniformity in the RC turns better with increasing working frequency,but it becomes worse to a certain degree if excessive losses are added.The proposed fast computing method provides a new way for 3D full-wave simulations of a RC or any other electromagnetic cavities in time domain,and it has certain referential value.