Cooperative diversity can mitigate keyhole effects in wireless MIMO systems

Oussama Souihli, Tomoaki Ohtsuki

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

6 Citations (Scopus)


A MIMO keyhole is a propagation environment such that the channel gain matrix has unit rank (single degree of freedom), irrespective of the number of deployed antennas or their correlations (spacing), thereby reducing the MIMO channel capacity to that of a SISO channel. Related literature seems to consider such degeneration hopeless. Contrary to this general belief, this paper demonstrates that cooperative diversity can mitigate keyhole effects. Precisely, provided that the source-relay channel is keyhole-free, we show that there exists a "cutoff" relay transmit power above which keyhole effects can be mitigated even when both the source-destination and the relay-destination channels incur keyhole effect. We explicit the closed form of this power threshold as function of the source transmit power and the channel matrices brought into play in the relay channel. Numerical examples confirm the relevance of our claim.

Original languageEnglish
Title of host publicationGLOBECOM 2009 - 2009 IEEE Global Telecommunications Conference
Publication statusPublished - 2009 Dec 1
Event2009 IEEE Global Telecommunications Conference, GLOBECOM 2009 - Honolulu, HI, United States
Duration: 2009 Nov 302009 Dec 4

Publication series

NameGLOBECOM - IEEE Global Telecommunications Conference


Other2009 IEEE Global Telecommunications Conference, GLOBECOM 2009
Country/TerritoryUnited States
CityHonolulu, HI

ASJC Scopus subject areas

  • Electrical and Electronic Engineering


Dive into the research topics of 'Cooperative diversity can mitigate keyhole effects in wireless MIMO systems'. Together they form a unique fingerprint.

Cite this