为了减少混响室时域全波仿真的计算量, 首次对混响室时域响应的预测做出探索研究。以改良矩阵束方法为基础, 提出一种计算效率更高的矩阵束方法, 并验证了该方法的正确性与稳定性。用复指数幂求和式对混响室的时域波形进行拟合, 利用该方法能够高效求解出拟合式中的各极点, 实现了对混响室时域响应的近似外推。由电场强度的前20 000步计算结果, 可快速预测得到后20 000步响应, 发现束参数比例取0.62左右时, 对多个采样点的电场均可得到良好的预测效果, 可保证仿真与预测相结合得到的结果与真实结果的频域相对误差小于15%。这种结合预测的仿真算法可节省计算量约50%。

In order to reduce the time-domain simulation time of reverberation chamber (RC), this paper investigates the means to predict time-domain responses of RC. A new kind of matrix pencil method (MPM) is proposed based on the modified MPM. Using the proposed method, a fitting formula for the former part of time-domain responses can be determined, which could be used to predict the later part. When the pencil ratio parameter is 0.62, acceptable results can be obtained using the first 20 000 original records to predict the following 20 000 responses. The relative error between the original and the semi-original semi-predicted signals in frequency domain can be guaranteed below 15%. In this way, the simulation time could be saved about 50% compared to the ordinary simulation.