不同于通常介质，在异向介质中的辐射场表现为内向波。本文从分析远场辐射边界条件和辐射功率两方面研究异向介质中源的辐射场具有的内向波特性，论证了内向波和因果律的一致性。论文以无穷长的线电流源置于异向介质圆柱体中为例，用数值模拟方法研究电磁场在异向介质圆柱体中的传播特性，验证异向介质辐射场的内向波。

Different from the usual media, the radiation field in the metamaterial behaves as the inward waves. The inward wave of a radiation field in the metamaterial has been studied on the electromagnetic principle of the far field radiation condition and the radiation power. It is shown that the inward wave is consistent with the causality. The FDTD numerical calculation method is used to simulate the wave propagation through an infinite long metamaterial cylinder, which is with a line source in its center. Therefore, the inward wave of the radiation field is validated in the metamaterial.