On the expected rate of slowly fading channels with quantized side information
2007 (English)In: IEEE Transactions on Communications, ISSN 0090-6778, E-ISSN 1558-0857, Vol. 55, no 4, 820-829 p.Article in journal (Refereed) Published
We study a multiple-layer variable-rate system employing quantized feedback to maximize the expected rate over a single-input single-output slowly fading Gaussian channel. The transmitter uses partial channel-state information, which is obtained via an optimized resolution-constrained feedback link, to adapt the power and to assign code layer rates, subject to different power constraints. To systematically design the system parameters, we develop a simple iterative algorithm that successfully exploits results in the study of parallel broadcast channels. We present the necessary and sufficient conditions for single-layer coding to be optimal, irrespective of the number of code layers that the system can afford. Unlike in the ergodic case, even coarsely quantized feed-back is shown to improve the expected rate considerably. Our results also indicate that with as little as one bit of feedback information, the role of multilayer coding reduces significantly.
Place, publisher, year, edition, pages
IEEE Communications Society , 2007. Vol. 55, no 4, 820-829 p.
broadcast channels, fading channels, feedback communications, information rates, power control, multiple-antenna systems, coded modulation, feedback, capacity, power, transmission
IdentifiersURN: urn:nbn:se:kth:diva-16586DOI: 10.1109/TCOMM.2007.894115ISI: 000246034300021ScopusID: 2-s2.0-34247180035OAI: oai:DiVA.org:kth-16586DiVA: diva2:334628
QC 20100525 QC 201112142010-08-052010-08-052011-12-14Bibliographically approved