The effects of time-delay spread on QAM with nonlinearity switched filters in a portable radio communications channel

Author

Chuang, Justin C I

Author_Institution

Bell Commun. Res., Red Bank, NJ, USA

Volume

38

Issue

1

fYear

1989

fDate

2/1/1989 12:00:00 AM

Firstpage

9

Lastpage

13

Abstract

A spectrally efficient quadrature amplitude modulation (QAM) scheme with a simple nonlinearly switched filter is shown to provide a signaling waveform that is free from both intersymbol interference and zero-crossing timing jitter in a flat-fading channel. This modulation with coherent detection is evaluated by a computer simulation in a frequency-selective fading channel. Timing offset between in-phase and quadrature rails is varied. The effects of receiver filter bandwidths are also studied. It is found that this modulation is resistant to delay spread with moderate spectral efficiency and low complexity in a portable radio system, as compared to other spectrally efficient modulations

Keywords

amplitude modulation; fading; mobile radio systems; telecommunication channels; QAM; coherent detection; computer simulation; flat-fading channel; frequency-selective fading channel; nonlinearity switched filters; portable radio communications channel; quadrature amplitude modulation; receiver filter bandwidths; signaling waveform; spectral efficiency; time-delay spread; timing offset; Bandwidth; Computer simulation; Delay; Filters; Frequency-selective fading channels; Intersymbol interference; Quadrature amplitude modulation; Rails; Receivers; Timing jitter;

fLanguage

English

Journal_Title

Vehicular Technology, IEEE Transactions on

Publisher

ieee

ISSN

0018-9545

Type

jour

DOI

10.1109/25.31129

Filename

31129