Interference cancelling equalizer (ICE) for mobile radio communication

Author

Yoshino, Hitoshi ; Fukawa, Kazuhiko ; Sukuki, H.

Author_Institution

NTT Mobile Commun. Network Inc., Kanagawa, Japan

Volume

46

Issue

4

fYear

1997

fDate

11/1/1997 12:00:00 AM

Firstpage

849

Lastpage

861

Abstract

This paper proposes an adaptive interference cancelling equalizer (ICE), which not only equalizes intersymbol interference (ISI), but also cancels cochannel interference (CCI) in the received signal in Rayleigh-fading environments, ICE is an adaptive multiuser detector for the frequency-selective fading environment commonly experienced by mobile communication channels. ICE employs a novel detection scheme: recursive least-squares maximum-likelihood sequence estimation (RLS-MLSE), which simultaneously estimates time-varying channel parameters and transmitted signal sequences. Diversity reception is used to enhance the signal detection performance of ICE. A computer simulation of a 40-kb/s QPSK time-division multiple-access (TDMA) cellular mobile radio system demonstrates the possibility of improving system capacity with ICE. Simulations of ICE with and without diversity are carried out under various fading conditions. For the maximum Doppler frequency of 40 Hz, ICE can attain an average bit-error rate (BER) of 10 ^-2 under a single CCI carrier-to-interference ratio (CIR) of ~14 dB. Moreover, ICE for two independent CCI signals can attain the average BER of 1.5×10^-2 with average CIR⩾-10 dB

Keywords

Rayleigh channels; access protocols; adaptive equalisers; adaptive signal detection; cellular radio; cochannel interference; coding errors; diversity reception; error statistics; fading; interference suppression; intersymbol interference; land mobile radio; least squares approximations; maximum likelihood estimation; quadrature phase shift keying; radiofrequency interference; recursive estimation; time division multiple access; time-varying channels; 40 kbit/s; BER; CCI; Dopper frequency; ISI; QPSK time division multiple access; RLS maximum likelihood sequence estimation; RLS-MLSE; Rayleigh fading environments; TDMA; adaptive multiuser detector; average bit error rate; carrier to interference ratio; cellular mobile radio system; cochannel interference; computer simulation; diversity reception; frequency selective fading; interference cancelling equalizer; intersymbol interference; mobile communication channels; mobile radio communication; received signal; recursive least squares; signal detection performance; system capacity; time-varying channel parameters; transmitted signal sequences; Bit error rate; Equalizers; Fading; Frequency; Ice; Interference cancellation; Intersymbol interference; Land mobile radio; Radiofrequency interference; Recursive estimation;

fLanguage

English

Journal_Title

Vehicular Technology, IEEE Transactions on

Publisher

ieee

ISSN

0018-9545

Type

jour

DOI

10.1109/25.653059

Filename

653059