On the use of simulation for the improvement and measurement validation of a smart antenna prototype

Abstract

The benefits of using smart antennas in a wireless mobile system have been thoroughly studied in recent years, showing an improvement in the antenna gain, a reduction of interfering power and, as a consequence, an increase in the system capacity. The real implementation and measurement of a smart antenna for the UMTS system are presented in this paper. Implementation impairments produce undesirable effects, such as frequency mismatch and coupling between RF channels. In order to minimize these effects, some simulations of the real system and the main non-ideal effects were carried out, so the analysis of these effects were affordable. Some solutions to the real implementation impairments were proposed and simulated, and the ones with better performance have been implemented and the obtained results are reported in this paper. Since traditional measurement methods are no longer suitable for the characterization of a smart antenna, a new method to measure the performance of the system is also introduced. The results show the feasibility of the system, which outperforms the performance of a conventional sectored antenna. An improvement of 6 dB in gain and 12.5 dB in carrier to interference ratio (CIR) was obtained with this prototype. The measurements were also validated by comparison with simulation results. © 2006 by Springer Science+Business Media, LLC.