Title :
Antenna verification for closed loop transmit diversity in UMTS
Author :
Nagaraj, Shirish ; Monogioudis, Pantelis
Author_Institution :
Open Innovation Lab., Lucent Technol. Bell Labs., Whippany, NJ, USA
Abstract :
We discuss the problem of estimating, at the mobile receiver, the weights applied by the base station transmitter when closed loop transmit diversity is used. This problem is referred to as antenna verification in the UMTS literature and performance of any closed loop scheme depends greatly on the accuracy of such an estimation. Maximum a posteriori and minimum mean square error formulations are sought, and corresponding antenna verification algorithms are derived under the two criteria. The problem of transmit power estimation is also addressed, since power estimates are required in the antenna verification algorithms. The tradeoffs associated with pilot power allocation in terms of its effects on minimizing the total transmitted power are also discussed.
Keywords :
3G mobile communication; diversity reception; least mean squares methods; maximum likelihood estimation; radio receivers; signal processing; MMSE estimation; UMTS; antenna verification; base station transmitter; closed loop transmit diversity; maximum a posteriori estimation; minimum mean square error estimation; mobile receiver; pilot power allocation; signal processing; total transmitted power minimization; transmit power estimation; 3G mobile communication; Base stations; Delay; Downlink; Feedback; Laboratories; Quadrature phase shift keying; Switches; Technological innovation; Transmitting antennas;
Conference_Titel :
Vehicular Technology Conference, 2004. VTC2004-Fall. 2004 IEEE 60th
Print_ISBN :
0-7803-8521-7
DOI :
10.1109/VETECF.2004.1404775