Improved Power Control for GSM/EDGE
Fredrik Hägglund · KTH Publication Database DiVA (KTH Royal Institute of Technology) · 2005
In GSM (Global System for Mobile Communication), a tradeoff between different goals is necessary to achieve the optimal system performance. Generally, high speech quality, high capacity and low power consumption are major goals. Power control is one of several techniques used to reach these goals. Power control regulates the signal strength with the aim to reduce the overall interference. Since radio environment and mixture of different user requirements may vary, there is an interest in making the setting of the power control target value automatically and dynamically. The target value should adapt to the environment and the situation. The method used is to extend the current power control with an outer loop that could adjust the quality parameter qdes. An attempt to use EMR data to adjust qdes is shown to have effects that eliminate the essential principle of power backoff to avoid the so called party effect, and is therefore not recommended. However, a method using the distribution of the transmitted power indicates more promising results. It is shown that there is high correlation between the number of satisfied users and the number of users within the regulating window, i.e. the number of users not limited by the maximum or minimum power levels.