Open AccessTighter low bound of achievable rate in downlink multiuser MIMO with imperfect CSIT
Author(s) -
Li Shichao,
Qiu Ling
Publication year - 2013
Publication title -
electronics letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.375
H-Index - 146
eISSN - 1350-911X
pISSN - 0013-5194
DOI - 10.1049/el.2013.0966
Subject(s) - telecommunications link , imperfect , mimo , transmitter , channel state information , upper and lower bounds , channel (broadcasting) , computer science , control theory (sociology) , mathematics , telecommunications , wireless , mathematical analysis , philosophy , linguistics , control (management) , artificial intelligence
One of the challenges to implementing downlink multiuser multiple‐input multiple‐output in practical systems is to overcome the detrimental impact of the imperfect channel state information at transmitter (CSIT). Researchers have derived a low bound to describe the imperfect CSIT's impact on the achievable rate. However, this low bound is not tight, especially when the quality of CSIT is poor. A tighter low bound using the exponential integral is proposed. A strict proof is given and the simulation results verify the tightness.