Title :
Transmit diversity using filtered feedback weights in the FDD/WCDMA system
Author :
Hottinen, Ari ; Wichman, Risto
Author_Institution :
Nokia Res. Center, Espoo, Finland
fDate :
6/22/1905 12:00:00 AM
Abstract :
The transmit diversity concept adopted for the FDD mode of the third generation WCDMA system in 3G standardization has an open-loop and a closed-loop mode. The open-loop mode applies space-time block coding and is provides full diversity for two transmit antennas. The closed-loop mode has two submodes, which both utilize downlink channel measurements and feedback signaling in controlling the phase and/or gain transmit weights in the two transmit antennas. In this paper we review the open- and closed-loop concepts and propose an enhancement to the feedback modes to further improve their performance. The enhanced feedback modes allow the base station to filter the feedback weights received from the terminal to improve beam resolution and system robustness
Keywords :
block codes; closed loop systems; code division multiple access; diversity reception; feedback; gain control; mobile radio; phase control; radio links; standardisation; telecommunication control; telecommunication signalling; telecommunication switching; transmitting antennas; 3G standardization; FDD; WCDMA; base station filtering; beam resolution; closed-loop mode; downlink channel measurements; enhanced feedback modes; feedback signaling; filtered feedback weights; gain transmit weight control; open-loop mode; performance; phase control; space-time block coding; system robustness; third generation system; transmit antennas; transmit diversity; Antenna measurements; Block codes; Downlink; Feedback; Gain measurement; Multiaccess communication; Open loop systems; Phase measurement; Standardization; Transmitting antennas;
Conference_Titel :
Broadband Communications, 2000. Proceedings. 2000 International Zurich Seminar on
Conference_Location :
Zurich
Print_ISBN :
0-7803-5977-1
DOI :
10.1109/IZSBC.2000.829223
