Isochronous and Anisochronous Modulation Schemes in Wireless Optical Communication Systems

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Mehdi Rouissat 1,* A. Riad Borsai 1 Mohammed Chikh-Bled 1

1. Laboratory of Telecommunications of Tlemcen (LTT) Dept Electronic, Faculty of thechnology Abou Bekr Belkaid University, PB 119 Tlemcen, Algeria

* Corresponding author.


Received: 24 Mar. 2012 / Revised: 15 Apr. 2012 / Accepted: 26 May 2012 / Published: 8 Jul. 2012

Index Terms

Isochronous, anisochronous, PPM, DPIM, bandwidth requirement, power efficiency, transmission capacity


The choice of the modulation format is one of the principle factors in realizing a high performance wireless optical communication system at a reasonable cost and acceptable complexity. The purpose of this paper is to make a comparison between isochronous and anisochronous modulation scheme categories from Discrete (digital) pulse time modulations (PTM) through the simplest scheme in each family; PPM and DPIM respectively, in term of bandwidth requirement, power efficiency and transmission capacity. This is done to give a wider view on the performance of such schemas under wide range of design parameters.
In this paper, the properties of PPM and DPIM have been analyzed, from this analysis it has been shown that DPIM or anisochronous modulation schemes in general are strong candidates when synchronization and transmission capacity are taken into account, and when it comes to power performance PPM or isochronous modulations are better.

Cite This Paper

Mehdi Rouissat, A. Riad Borsai, Mohammed Chikh-Bled, "Isochronous and Anisochronous Modulation Schemes in Wireless Optical Communication Systems ", International Journal of Information Engineering and Electronic Business(IJIEEB), vol.4, no.3, pp.19-25, 2012. DOI:10.5815/ijieeb.2012.03.03


[1]J. R. Barry: "Wireless infrared communications", London: Kluwer, 1994.

[2]M.Ijaz, O. Adebanjo, S. Ansari, Z. Ghassemlooy, S. Rajbhandari, H. Le Minh, A. Gholami and E. Leitgeb "Experimental Investigation of the Performance of OOK-NRZ and RZ Modulation Techniques under Controlled Turbulence Channel in FSO Systems". 2010 PGNet.

[3]B. Wilson, and Z. Ghassemlooy, (1993): Pulse time modulation techniques for Optical communications. IEE proceedings-J, vol. 140, no. 6, pp. 346–357.

[4]J.M. Kahn and J.R. Barry, "Wireless Infrared Communications", Proc. of the IEEE, pp. 265-298, February 1997.

[5]J. M. Kahn, and J. R. Barry, "Wireless infrared communications," Proceedings of IEEE, vol. 85, no. 2, pp. 265–298, Feb. 1997.

[6]J. M. H. Elmirghani, and R. A. Cryan, " Analytic and numerical modelling of optical fibre PPM slot and frame spectral properties with application to timing extraction", IEE Proc. Commun., Vol. 141, No. 6, pp. 379-389. 1994.

[7]Z. Ghassemlooy, A. R. Hayes, N. L. Seed, and E. D. Kaluarachchi, "Digital pulse interval modulation for optical communications," IEEE Commun. Magaz., pp. 95–99, Dec. 1998

[8]E. D. Kaluarachchi, "Digital pulse interval modulation for optical communication systems," Ph.D. thesis, Sheffield Hallam Univ., U.K., 1997.

[9]U. Sethakaset and T. A. Gulliver: Differential amplitude pulse-position modulation for indoor wireless optical channels. IEEE Global Telecom. Con. (GLOBECOM'04), vol. 3, pp. 1867–1871. 2004.