Per-Antenna Constant Envelope Precoding for Large Multi-User MIMO Systems
2013 (English)In: IEEE Transactions on Communications, ISSN 0090-6778, E-ISSN 1558-0857, Vol. 61, no 3, 1059-1071 p.Article in journal (Refereed) Published
We consider the multi-user MIMO broadcast channel with M single-antenna users and N transmit antennas under the constraint that each antenna emits signals having constant envelope (CE). The motivation for this is that CE signals facilitate the use of power-efficient RF power amplifiers. Analytical and numerical results show that, under certain mild conditions on the channel gains, for a fixed M, an array gain is achievable even under the stringent per-antenna CE constraint. Essentially, for a fixed M, at sufficiently large N the total transmitted power can be reduced with increasing N while maintaining a fixed information rate to each user. Simulations for the i.i.d. Rayleigh fading channel show that the total transmit power can be reduced linearly with increasing N (i.e., an O(N) array gain). We also propose a precoding scheme which finds near-optimal CE signals to be transmitted, and has O(MN) complexity. Also, in terms of the total transmit power required to achieve a fixed desired information sum-rate, despite the stringent per-antenna CE constraint, the proposed CE precoding scheme performs close to the sum-capacity achieving scheme for an average-only total transmit power constrained channel.
Place, publisher, year, edition, pages
Institute of Electrical and Electronics Engineers (IEEE) , 2013. Vol. 61, no 3, 1059-1071 p.
Multi-user, constant envelope, per-antenna, large MIMO, GBC
Engineering and Technology
IdentifiersURN: urn:nbn:se:liu:diva-93866DOI: 10.1109/TCOMM.2013.012913.110827ISI: 000318420800022OAI: oai:DiVA.org:liu-93866DiVA: diva2:627332
Funding Agencies|Swedish Foundation for Strategic Research (SSF)||ELLIIT||Knut and Alice Wallenberg Foundation||Center for Industrial Information Technology at ISY, Linkoping University (CENIIT)||2013-06-112013-06-112016-08-31