Software Engineering

ISSN Online: 2376-8037 ISSN Print: 2376-8029

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Volume 5, Issue 3, May 2017

  • Authors: Mfon Emenyi, Kufre Udofia M., Obinwa Christian Amaefule

    Abstract: This paper presents an efficient algorithm for determination of optimal path length of terrestrial line of sight microwave communication link. The algorithm computes and adjusts the path length based on the difference between the maximum fade depth the link can accommodate and the actual fade depth that is expected in the link. The algorithm uses Newton-Raphson iteration method to adjust the path length until it arrives at the optimal path length at which the maximum fade depth the link can accommodate and the actual fade depth that is expected in the link at the given set of link parameters. A numerical example is performed for a Ku-band microwave link at 12 GHz. The results show that after 4 cycle the algorithm converged when the path length dropped from its initial value of 19.9903km to the optimal value of 5.89Km. In addition, for free space, the initial value of 140.40dB drops to a value of 129.43dB at the optimal point and maximum fade depth dropped from initial value of 104.04dB to optimal value of 30.65dB.

    Received: Jan. 3, 2017 Accepted: Jan. 18, 2017 Published: Jun. 27, 2017

    DOI: 10.11648/j.se.20170503.11 View: Downloads:

  • Authors: Fidelis Osanebi Chucks Nwaduwa, Wali Samuel, Asuquo Ifiok Okon

    Abstract: In this paper, an approach for optimizing Hata pathloss model based on terrain roughness parameter is presented. The study is based on field measurement of received signal strength and elevation profile obtained in a suburban area for a GSM network in the 800 MHz frequency band. Mostly, standard deviation of elevation is used to characterize terrain roughness. However, in this paper, the mean elevation and the standard deviation of elevation are used separately to minimize the error using least square method. The results show that the untuned Hata model has a RMSE of 44.58 dB and prediction accuracy of 65.07%. On the other hand, both the pathloss predicted by the mean elevation tuned Hata model and the pathloss predicted by the standard deviation of elevation tuned Hata model have the same RME of 6.23 dB and prediction accuracy of 96.06%. Also, the terrain roughness correction factors are the same value (that is, CTSDV=CTMean=44.13848). Finally, with the RMSE of about 6 dB, it can be concluded that the terrain roughness parameter-based tuning approach can effectively be used to minimize the prediction error of the Hata model within the acceptable value which is about 7dB to 10 dB for urban and rural areas.

    Received: Jan. 3, 2017 Accepted: Jan. 10, 2017 Published: Aug. 29, 2017

    DOI: 10.11648/j.se.20170503.12 View: Downloads: