Optimum Weight Generation Method for Adaptive Antenna Array Transmit Diversity in W-CDMA Forward Link(Special Section on Spread Spectrum Techniques and Applications)

概要

論文の詳細を見る
This paper investigates the optimum transmitantenna-weight generation method for adaptive antenna array transmit diversity(AAA-TD)in the W-CDMA forward link: AAA-TD with beam and null steering(BNST), AAA-TD with beam steering(BST), or switched beam transmit diversity with fixed weights(SBTD-FW). The achievable BER performance after carrier frequency calibration in the transmit beam pattern is compared among the three methods assuming a different carrier frequency in a 2-GHz band with the carrier separation of 184.5MHz based on computer simulations. The simulation results show that the achievable BER performance in the forward link using AAA-TD with BNST is almost identical to that using AAA-TD with BST when there are many more interfering users than there are array antennas, except for the special case when a small number of higher rate users exists in the reverse link. This is because by performing carrier frequency calibration, the directions of the beam mulls are shifted from the real directions of arrival(DOAs)of the interfering users. However, we also show that the required transmit E_b/N_o at the average BER of 10^<-3> using AAA-TD with BST is decreased by approximately 1.0 to 1.2dB compared to that using SBTD-FW with 12 beams.
社団法人電子情報通信学会の論文
2001-12-01