| 摘要: |
| 针对Okumura-Hata模型在不同区域对电波传播衰减的预测与实测难以匹配的问题，提出了一种Okumura-Hata模型修正方法。提取Okumura-Hata模型的各参数作为带约束条件的优化变量，以预测值与实测值的均方根误差和平均误差的加权和构造适应度函数，运用萤火虫算法进行优化实现Okumura-Hata模型在西安市区的本地化。在萤火虫算法中引入了“基因突变”和“优胜劣汰”操作，形成了一种改进型算法。基于大量实测数据的模型修正结果表明，所提方法可使电波损耗的预测值与实测值的均方根误差达到理论最小值9.585 9 dB，具有可行性。与基本萤火虫算法相比，改进的算法全局搜索能力更强，收敛速度更快。 |
| 关键词: 电波传播 Okumura-Hata模型 萤火虫算法 模型修正 全局搜索能力 |
| DOI： |
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| 基金项目:国家自然科学基金重点资助项目(61631015) |
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| Application of improved firefly algorithm in Okumura-Hata model updating |
| LIU Baosheng,PAN Lin,LI Zhangyi |
| () |
| Abstract: |
| To solve the problem that the Okumura-Hata model is not suitable for any area,a new approach for modifying Okumura-Hata model is proposed.The approach extracts Okumura - Hata model’s parameters as the optimization variables with constraint conditions,and constructs fitness function using the root mean square error(RMSE) and the mean error(ME) between predicted values and measured values. Then,the new parameters of Okumura - Hata model will get after the model is optimized by Firefly algorithm. Besides,an improved Firefly algorithm based on “gene mutation” and “law of survival of the fittest” is proposed. The simulation results show that the RMSE of the updated model can approach the theoretical minimum limit 9.585 9 dB. Compared with the basic Firefly algorithm,the improved one has a stronger global searching ability and a faster convergence speed. |
| Key words: electromagnetic wave propagation Okumura-Hata model firefly algorithm model updating global search ability |
