Studies on the energy consumption savings versus the service quality in mobile telecommunications

In previous papers we pointed out how the "Power Saving" method can be usefully used to lower the energy consumption of a base transceiver station (BTS). It consists in switching off the redundant channels during low traffic periods that can occur during the day or week. However, this saving should be pursued with minimum or no losses in terms of the quality of the service provided to the final user; a parameter to trace is the number of lost calls for the lack of available channels. For example, the switching off of the unneeded channels should occur when the fluctuation of the number of calls and their lengths permit to foresee a quite long period of low demand. Moreover, the channel control algorithm should be adequately smart to address a coming high demand period, providing a fast activation of the needed channels. This is obtained with a control algorithm and with a fine tuning of its parameters. In this paper we test the control algorithm with Monte Carlo simulations. Then we check the algorithm for the best numerical and BTS parameters finding the range of savings that can be obtained for standard cases. Finally, we apply the code to the behaviour of a prototypal BTSs under a wide range of loads so it is possible to check the best parameters giving the maximum power saving while still safeguarding good communication levels. Data coming from a recent auditing of Italian BTSs (number of calls, calls length, maximum number of possible call and other BTS parameters) and from in situ measurements, are used as tuning parameters. We show that considerable savings in the power consumptions are possible, depending on the characteristics of the site, without loss of service quality.