UPM Institutional Repository

Spectrum efficiency enhancement in dynamic space coded multiple access (DSCMA) system


Ng, Chee Kyun and Noordin, Nor Kamariah and Mohd Ali, Borhanuddin and Jamuar, Sudhanshu Shekhar and Ismail, Mahamod (2010) Spectrum efficiency enhancement in dynamic space coded multiple access (DSCMA) system. Wireless Personal Communications, 53 (2). pp. 253-267. ISSN 0929-6212; ESSN: 1572-834X


In cellular mobile communication systems using coded modulations, the spectrum efficiency of the system is related to the number of available codes. Recently, large area synchronous (LAS) CDMA codes, which exhibit a region called interference free window (IFW) within some delay-spread, have been accepted as one of fourth-generation (4G) wireless communication systems. However, the number of synthesized LAS codes is very low due to the low duty ratio of the sequence. In this paper, a dynamic space coded multiple access (DSCMA) scheme which utilizes the spatial diversity from smart antenna system is proposed to overcome the low spectrum efficiency in LAS CDMA system. In the DSCMA a modified version of LAS codes called LAS even ternary (LAS-ET) codes is proposed. These codes are used together with a novel algorithm called dynamic space code (DSC), which will decrease the code length so that the spectrum efficiency can be increased. By taking advantage of dynamic code reuse assignment in spatial diversity, the spectrum efficiency of the DSCMA can be further increased significantly.

Download File

PDF (Abstract)
Spectrum Efficiency Enhancement in Dynamic Space Coded Multiple Access.pdf

Download (83kB) | Preview

Additional Metadata

Item Type: Article
Divisions: Faculty of Engineering
DOI Number: https://doi.org/10.1007/s11277-009-9682-7
Publisher: Springer
Keywords: Spectrum efficiency; LAS CDMA; IFW; Smart antenna; Code reuse; Duty ratio; Beamwidth
Depositing User: Anas Yahaya
Date Deposited: 31 Mar 2011 10:15
Last Modified: 01 Dec 2016 08:24
Altmetrics: http://www.altmetric.com/details.php?domain=psasir.upm.edu.my&doi=10.1007/s11277-009-9682-7
URI: http://psasir.upm.edu.my/id/eprint/11429
Statistic Details: View Download Statistic

Actions (login required)

View Item View Item