PPM versus PCM for optical local-area networks

Author

Martin, J.D. ; Hausien, H.H.

Author_Institution

Sch. of Electron. & Electr. Eng., Bath Univ., UK

Volume

139

Issue

3

fYear

1992

fDate

6/1/1992 12:00:00 AM

Firstpage

241

Lastpage

250

Abstract

Pulse-position modulation (PPM) is presented within the context of a local-area network (LAN) application. A simplified analysis is used to calculate the advantage of converting from pulse-code modulation (PCM) to PPM signalling in a LAN, assuming in each case the same fibre network and the same optical transmitting device. Although PPM exploits its wide bandwidth to give greater sensitivity in noise, the true system advantage is obtainable only by using a large peak-to-mean-power ratio in the transmitter. It is shown that this performance is possible for both a laser diode and for an edge-emitting LED. An experimental system is reported, operating at a data rate of 4 Mbit/s, and good correspondence with theory is obtained. Design procedures are given for broad classes of situation.<>

Keywords

local area networks; optical links; pulse position modulation; pulse-code modulation; 4 Mbit/s; LAN; PPM signalling; design procedures; edge-emitting LED; fibre network; laser diode; optical local-area networks; optical transmitting device; peak-to-mean-power ratio; pulse-code modulation; pulse-position modulation; wide bandwidth;

fLanguage

English

Journal_Title

Communications, Speech and Vision, IEE Proceedings I

Publisher

iet

ISSN

0956-3776

Type

jour

Filename

145196