Distributed MIMO-CDMA system: effects of spreading sequences on sum capacity

Author

Ni, Zhi ; Li, Daoben

Author_Institution

Sch. of Inf. Eng., Beijing Univ. of Posts & Telecommun., China

Volume

1

fYear

2004

fDate

29 Aug.-1 Sept. 2004

Firstpage

165

Abstract

Distributed multiple-input multiple-output (MIMO) system is a new architecture for a wireless communication system with distributed multiple antennas. In this paper, the uplink sum capacity of distributed MIMO system with wideband code-division multiple-access (CDMA) technology under multipath fading channels is studied carefully. Single-user decoders with different assumptions of interference knowledge are used in the receivers. The spreading sequences of the CDMA system are assumed to employ loosely synchronized (LS) spreading sequences and random spreading sequences, respectively. LS codes exhibit a so-called interference free window (IFW), where both the auto-correlation and cross-correlation of the codes become zero. Therefore LS sequences have the promise of mitigating the effects of inter symbol interference (ISI) and multiple access interference (MAI) in multipath fading channels. Simulation results show that due to the perfect correlation properties of LS spreading sequences, the uplink sum capacity of the distributed MIMO-CDMA system using LS sequences can substantially outperform that of the system using random spreading sequences.

Keywords

MIMO systems; antenna arrays; broadband networks; code division multiple access; fading channels; intersymbol interference; multipath channels; radio networks; random sequences; distributed MIMO-CDMA system; distributed multiple antenna; interference free window; intersymbol interference; loosely synchronized spreading sequence; multipath fading channel; multiple access interference; multiple-input multiple-output system; random spreading sequence; single-user decoder; uplink sum capacity; wideband code-division multiple-access technology; wireless communication system; Base stations; Decoding; Fading; Intersymbol interference; Large-scale systems; MIMO; Mobile communication; Multiaccess communication; Multiple access interference; Wireless communication;

fLanguage

English

Publisher

ieee

Conference_Titel

Communications, 2004 and the 5th International Symposium on Multi-Dimensional Mobile Communications Proceedings. The 2004 Joint Conference of the 10th Asia-Pacific Conference on

Print_ISBN

0-7803-8601-9

Type

conf

DOI

10.1109/APCC.2004.1391674

Filename

1391674