A new propagation model is proposed for estimating the attenuation of wireless communication signals in woodland environments. After rainfall or snowfall, the components of the woodland area become moist which degrades the received signal level. To take this into account, the model considers wet/dry states of the foliage, and its dependency on the operating frequency. The parameters of the propagation loss model are optimized using the least squares method. To demonstrate the validity and usefulness of the model, computed results are compared with measured data where excellent matching is observed. It is noted that not only the foliage and rainfall affect the propagation phenomenon, but also wet foliage condition after rainfall contributes to the fading of the wave.

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In this paper, a comprehensive study is presented whereby genetic algorithm optimization (GAO) is used to find the best arrangement of three‐phase high‐voltage transmission line (TL) conductors, that minimizes emitted electric and magnetic fields (EMFs), maximizes power capacity, and avoids corona. Moreover, a financial cost study is conducted in order to show the feasibility of implementing such rearrangement, where construction costs are compared with the impact on a populated area in close proximity to the line. To facilitate applying the procedure of this paper, a detailed description of each step is provided. Both single circuit as well as double circuit transmission lines are considered, and bundled conductors are analyzed. To demonstrate the validity and usefulness of the mathematical formulation and MATLAB computer codes, computed results are compared with measured data where good agreement is observed. To show that using GAO for solving high voltage line problems is an alternative to other robust optimization techniques such as particle swarm optimization (PSO), GAO solutions are compared with PSO solutions. The GAO results are also compared with the unoptimized results, where significant improvements can be seen. Since according to this algorithm, line conductors move freely throughout the solution space in an attempt to find the best solution, it is important to restrict this movement in order to adhere to the separation limits of the transmission line international standards IEC‐71.

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