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

Chee Kyun Ng, Nor Kamariah Noordin, Borhanuddin Mohd Ali, Sudhanshu Shekhar Jamuar, Mahamod Ismail

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

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.

Original languageEnglish
Pages (from-to)253-267
Number of pages15
JournalWireless Personal Communications
Volume53
Issue number2
DOIs
Publication statusPublished - Apr 2010

Fingerprint

Code division multiple access
Smart antennas
Mobile telecommunication systems
Communication systems
Modulation

Keywords

  • Beamwidth
  • Code reuse
  • Duty ratio
  • IFW
  • LAS CDMA
  • Smart antenna
  • Spectrum efficiency

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Computer Science Applications

Cite this

Spectrum efficiency enhancement in dynamic space coded multiple access (DSCMA) system. / Ng, Chee Kyun; Noordin, Nor Kamariah; Ali, Borhanuddin Mohd; Jamuar, Sudhanshu Shekhar; Ismail, Mahamod.

In: Wireless Personal Communications, Vol. 53, No. 2, 04.2010, p. 253-267.

Research output: Contribution to journalArticle

Ng, Chee Kyun ; Noordin, Nor Kamariah ; Ali, Borhanuddin Mohd ; Jamuar, Sudhanshu Shekhar ; Ismail, Mahamod. / Spectrum efficiency enhancement in dynamic space coded multiple access (DSCMA) system. In: Wireless Personal Communications. 2010 ; Vol. 53, No. 2. pp. 253-267.
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