中文摘要：

将森林看成空气和植物组成的混合物，应用两相混合物折射模型求解了森林的等效介电常数，通过与实验结果的对比，验证了该模型的正确性。将该森林介电常数求解方法引入到抛物方程的森林模型中，改进了抛物方程的森林模型。相对于传统的森林环境电波传播模型，该模型能考虑森林各组成要素对电波传播的影响，更适合于实际不同地区、不同种类植物分布的森林环境中电波传播特性的求解。此外，引入了非均匀网格技术，有效提高了大区域森林环境中电波传播问题的求解效率。最后基于该模型仿真分析了森林的植物体积含量、重量含水量等要素对电波传播特性的影响。

英文摘要：

Regarding the forest as a mixture of air and plants, the refractive model is used to obtain the effective dielectric constant of forest, and the correctness is verified by comparing with the experimental result. The parabolic equation model of forest can be improved by introducing the method of effective dielectric constant for forest. Compared with the traditional model, the improved model takes into account the effect of various elements of forest on radio wave propagation and is more suitable for the radio propagation problems with different plant species in different regions. Otherwise the non-uniform mesh technique is introduced and improves the computational efficiency effectively. Finally, in this paper we analyze the effects of various elements of forest, such as the volume content of plant, the gravimetric moisture content, etc. on the radio propagation.