Overloaded WH-Spread CI/MC-CDMA with Iterative Interference Cancellation

Author

Mukherjee, Mithun ; Kumar, Preetam

Author_Institution

Dept. of Electr. Eng., Indian Inst. of Technol. Patna, Patna, India

Volume

15

Issue

12

fYear

2011

fDate

12/1/2011 12:00:00 AM

Firstpage

1391

Lastpage

1393

Abstract

This paper addresses a novel Walsh-Hadamard (WH)-spread multicarrier code division multiple access (MC-CDMA) system which employs carrier interferometry (CI) codes to achieve improved bit error rate (BER) performance. In frequency selective channel, phase characteristic of CI codes ensures better estimates of received WH-spread CI/MC-CDMA signal. In this paper an iterative receiver structure is used for decoding WH-spread CI/MC-CDMA signal. Estimation of multiple access interference (MAI) becomes more reliable with time and frequency diversities of CI/MC-CDMA signal with spreading gain diversity of WH code over multipath channel. It is shown by simulation that WH-spread CI/MC-CDMA provides 2 dB gain at a BER of 1e-03 after 6^th iteration with soft decision subcarrier parallel interference cancellation (SDSub-PIC) at 25% overload compared to CI/MC-CDMA.

Keywords

code division multiple access; error statistics; interference suppression; interferometry; iterative methods; multipath channels; CI code; WH code; Walsh-Hadamard-spread multicarrier code division multiple access; bit error rate performance; carrier interferometry code; decoding WH-spread CI-MC-CDMA signal; frequency diversity; frequency selective channel; iterative interference cancellation; iterative receiver structure; multipath channel; multiple access interference; overloaded WH-spread CI-MC-CDMA; soft decision subcarrier parallel interference cancellation; Bit error rate; Complexity theory; Multicarrier code division multiple access; OFDM; Rayleigh channels; CI/MC-CDMA; Overload; PIC; WH-spread CI/MC-CDMA;

fLanguage

English

Journal_Title

Communications Letters, IEEE

Publisher

ieee

ISSN

1089-7798

Type

jour

DOI

10.1109/LCOMM.2011.102611.111626

Filename

6072193