CDMA vs. OFDM for wideband cellular systems

Author

Peng, Yong ; Mandyam, Giridhar ; Rajan, Dinesh

Author_Institution

Dept. of Electr. Eng., Southern Methodist Univ., Dallas, TX

fYear

2008

fDate

26-29 Oct. 2008

Firstpage

958

Lastpage

962

Abstract

In this paper, we compare the downlink transport spectral efficiency (TSE) of DS-CDMA using RAKE receiver, LMMSE receiver, the multiuser cyclic prefix OFDM and zero padding OFDM in wideband cellular systems. The TSE is defined as the distance weighted sum rate per unit bandwidth. It is derived in terms of the output signal to interference noise ratio as the sum of products of bits and the distances over which they are carried per unit time and bandwidth. Analytical expressions for TSE are derived and then numerically evaluated to compare the performance of CDMA and OFDM for different channel conditions. Unlike spectral efficiency, the TSE does not monotonically decrease with base station density. The cell size should be carefully chosen in order to optimize the TSE.

Keywords

OFDM modulation; broadband networks; cellular radio; code division multiple access; least mean squares methods; radio receivers; spread spectrum communication; DS-CDMA; LMMSE receiver; RAKE receiver; base station density; downlink transport spectral efficiency; multiuser cyclic prefix OFDM; output signal to interference noise ratio; wideband cellular systems; zero padding OFDM; Bandwidth; Downlink; Fading; Interference; Multiaccess communication; Multipath channels; OFDM; RAKE receivers; Signal to noise ratio; Wideband;

fLanguage

English

Publisher

ieee

Conference_Titel

Signals, Systems and Computers, 2008 42nd Asilomar Conference on

Conference_Location

Pacific Grove, CA

ISSN

1058-6393

Print_ISBN

978-1-4244-2940-0

Electronic_ISBN

1058-6393

Type

conf

DOI

10.1109/ACSSC.2008.5074553

Filename

5074553