On the Asymptotic Sum-Rate in 2xNx2 Dual-Hop Relaying with Quality based Channel Reporting and Relay Selection
2007 (English)In: 2007 IEEE 18TH INTERNATIONAL SYMPOSIUM ON PERSONAL, INDOOR AND MOBILE RADIO COMMUNICATIONS, VOLS 1-9, IEEE , 2007, 2508-2512 p.Conference paper (Refereed)
In this paper, we prove the asymptotic sum-rate growth like 2 log log N can be achieved in 2 times N times 2 dual-hop relaying systems with 2 transmit antennas at a base station (or a source), N > 2 single receive/transmit antenna relays and 2 destination users with a single antenna. The capacity is achieved when the base station transmits with zero-forcing beamforming and the relays that actively transmit are selected with semi-orthogonal relay selection principle. Since the base station should know the channel information to the relays, the feedback load grows prohibitively large if N rarr infin. To reduce the feedback load from the relays to the base station, we use quality-based channel state reporting (QBR). Numerical results show that the sum-rate achieved by N relays gets close to its multiuser counterpart if the amplifying gain at the relay is large. We also show how QBR is effective in reducing the feedback load when N is large.
Place, publisher, year, edition, pages
IEEE , 2007. 2508-2512 p.
Computer and Information Science
Research subject SRA - ICT
IdentifiersURN: urn:nbn:se:kth:diva-31049DOI: 10.1109/PIMRC.2007.4394625ISI: 000253402501210ISBN: 978-1-4244-1144-3OAI: oai:DiVA.org:kth-31049DiVA: diva2:402301
18th IEEE International Symposium on Personal, Indoor and Mobile Radio Communication. Athens, GREECE. SEP 03-07, 2007
QC 201111142011-03-072011-03-072011-11-14Bibliographically approved