Reverse Link Performance Improvement for Dynamic Parameter Controlled OFDM Using Alamouti Coded Heterogeneous Polarization Antennas

摘要

The combination of OFDM and multiple antennas in either the transmitter or receiver is attractive to increasing the diversity gain. However, multiple antennas system requires an antenna separation of 5～10 A to keep the correlation coefficient below 0.7 for the full space diversity, so this may be difficult to implement in mobile station with high mobility. Recently, the polarization transmit diversity is considered in mobile station. However, polarization transmit diversity requires twice transmit powers to compare with the conventional transmit diversity, since only vertical type polar antenna cannot receive the horizontal signal components. Moreover, the cross polarization discriminator (XPD) is shown about 5～15 dB. Therefore, it is difficult to obtain full diversity, since a large imbalance in the received power would render the whole diversity system worthless. To reduce these problems, we propose a dynamic parameter controlled OFDM using Alamouti coded heterogeneous polarization antennas for obtaining the equal power. From the simulated results, the proposed system shows better BER performance than that of the conventional STBC/OFDM.