EURASIP Journal on Applied Signal Processing 
Volume 2004 (2004), Issue 5, Pages 662-675
doi:10.1155/S1110865704310061

Generalized Alamouti Codes for Trading Quality of Service against Data Rate in MIMO UMTS

Christoph F. Mecklenbräuker1 and Markus Rupp2

1Forschungszentrum Telekommunikation Wien (ftw), Donau-City Straße 1, Vienna 1220, Austria
2Institut für Nachrichtentechnik und Hochfrequenztechnik, Technische Universität Wien, Gusshausstraße 25-29, Vienna 1040, Austria

Received 17 December 2002; Revised 26 August 2003

Abstract

New space-time block coding schemes for multiple transmit and receive antennas are proposed. First, the well-known Alamouti scheme is extended to NT=2m transmit antennas achieving high transmit diversity. Many receiver details are worked out for four and eight transmit antennas. Further, solutions for arbitrary, even numbers (NT=2k) of transmit antennas are presented achieving decoding advantages due to orthogonalization properties while preserving high diversity. In a final step, such extended Alamouti and BLAST schemes are combined, offering a continuous trade-off between quality of service (QoS) and data rate. Due to the simplicity of the coding schemes, they are very well suited to operate under UMTS with only very moderate modifications in the existing standard. The number of supported antennas at transmitter alone is a sufficient knowledge to select the most appropriate scheme. While the proposed schemes are motivated by utilization in UMTS, they are not restricted to this standard.