Measurement-Based Analysis and Evaluation of Performance of Mobile Phones Base Stations Antenna

摘要

In the mobile communications field, multiple antenna systems such as array antenna systems promise increases in the performances of the mobile communication systems without the need for additional radio spectrum or transmit power. By an appropriate selection of the antenna pattern of beam, the desired signals can be reduced and the performance of the mobile communication system enhanced. The performance evaluation of a mobile base station antenna can be done by measurements on test routes or by calculations using measured direction-of-arrival distributions and the measured or calculated radiation pattern of the antenna. Measurements on antennas of mobile base stations require a lot of effort in cells used in the cities. In this work, measurements have been done in five sites in Sulaimani city in Iraq. The objective of this work is the introduction of some types of array antennas used in mobile communication systems, and discussing the suitability of array antenna for GSM base stations. The theoretical results obtained for the three types of array antennas are compared with respect to the half power beam-width, the gain, and the radiation pattern, using MATLAB. As an example measurements obtained from a selected sites using the latest tools available (TEAMS) are based on radiation pattern, half power beam-width, and the gain of the base station antennas. These results are compared with prediction pattern of the antenna used by the selected sites. The differences between prediction results and the field measurements are given as a percentage differences. The normalized mean absolute differences are in the range (12.3% - 22.185%).