Allocation of feedback bits among users in broadcast MIMO channels

Bruno Clerckx, Gil Kim, Joonil Choi, Sungjin Kim

Research output: Chapter in Book/Report/Conference proceedingConference contribution

9 Citations (Scopus)


Given a contraint on the total amount of feedback overhead, we investigate the allocation of feedback bits (i.e. codebook sizes) among users in a limited feedback Zero Forcing Beamforming-based MU-MIMO scheme where users have the opportunity to adapt their codebooks as a function of their own channel statistics. We consider both single-polarized and dual- polarized scenarios. Using upper bounds on the total rate loss incurred by quantization (previously derived by the authors), the optimal bit allocation strategy among users is derived as a function of the users channel statistics and SNR. Closed form solutions of the optimal bit allocation at low and high SNR are also derived. It is shown that in single-polarized scenarios (resp. dual-polarized scenarios) at high SNR it is beneficial to allocate more bits to users experiencing rank deficient transmit correlation matrices (resp. low cross-polarization discrimination XPD) than to users experiencing well conditioned correlation matrices (resp. large XPD), while an opposite allocation should be done at low SNR. Simulation results are shown to confirm analytical derivations.

Original languageEnglish
Title of host publication2008 IEEE Global Telecommunications Conference, GLOBECOM 2008
Number of pages5
Publication statusPublished - 2008
Event2008 IEEE Global Telecommunications Conference, GLOBECOM 2008 - New Orleans, LA, United States
Duration: 2008 Nov 302008 Dec 4

Publication series

NameGLOBECOM - IEEE Global Telecommunications Conference


Other2008 IEEE Global Telecommunications Conference, GLOBECOM 2008
Country/TerritoryUnited States
CityNew Orleans, LA

ASJC Scopus subject areas

  • Electrical and Electronic Engineering


Dive into the research topics of 'Allocation of feedback bits among users in broadcast MIMO channels'. Together they form a unique fingerprint.

Cite this