Maximising Bandwdith Efficency of Statistical Multiplexer Architecture using Frame Droping Methods

Asadullah Shah, Humaira Dar, Iftikhar A Syed


It is generally considered that remote and rural telephone users generate less traffic as compared to urban area users. This lowers the attraction of investment in rural areas by the telecommunications companies and service providers. The financial implications of wiring a vast area for low telephone traffic causes most telephone service providers to ignore those regions. Still, it is known that telecommunications are essential to the economic development of a region and that traffic increases rapidly as soon as the service is available. A satellite–based telephone network can provide efficient long distance telephone service to remote rural communities at a lower cost than land-based wired networks in most cases. Mobile satellite systems already provide this service, but are limited in capacity and charge high per-minute fees for the satellite link. Small earth stations and GEO satellites can provide this service more efficiently and at lower cost. On top of that, bandwidth efficient multiplexing with compressed speech, Voice Activity Detection (VAD) and Packet discarding methods can even further reduce the cost of service for the users in rural areas. In this paper, Statistical Time Division Multiplexer (STDM) architecture was simulated. Two packet discarding methods, random packet discarding and cyclic packet discarding are used to maximize bandwidth utilization along with VAD. Results indicate that considering monologue speech source, with 80%, activity for each 6.4 kbps sources, on a channel of 64 kbps, 12 users can be allowed to be multiplexed instead of 9, therefore a Digital Speech Interpolation (DSI) advantage of 1.33 is achieved with 3% packet loss. Furthermore, it is observed that cyclic packet discarding technique perform better than random packet discarding in terms of subjective quality

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Chief Editor

Prof. Dr. Tariq Rahim Soomro 
College of Computer Science & Information Systems


Dr. Muhammad Mansoor Alam
 Professor and Associate Dean
 College of Computer Science & Information Systems

Associate Editors

Engr. Syed Mubashir Ali
Senior Lecturer & Course Coordinator
College of Computer Science & Information Systems

Publication Coordinator
Humaira Kanwal

Editorial Advisory Board (Internal)

Dr. Syed Irfan Hyder
Dr. S.M. Aqil Burney
Dr. Ejaz Ahmed
Dr. Mohammad Irshad Khan
Dr. Shahid Amjad
Dr. Fatima Riaz
Dr. Insia Hussain
Dr. Dr. Ehsan Rehman
Dr. Imran Majid
Dr. Khurram Iqbal
Dr. Zeeshan Shahid
Dr. Seema Ansari
Dr. Sumaira Khan


Editorial Advisory Board (International)

Prof. Dr. Mazliham Mohd Su'ud, President, Universiti Kuala Lumpur, Malaysia
Prof. Dr. Ghassan Al-Qaimari, President, Emirates College of Technology, Abu Dhabi, UAE
Prof. Dr. Patrice Boursier, Universite de La Rochelle, La Rochelle, France
Prof. Dr. Mudassir Uddin, Professor, University of Karachi, Pakistan
Dr. Nadeem Doudpota, Associate Professor, Al-Baha University, KSA
Dr. Haithem Abdelrazaq Almefleh, Associate Professor, Yarmouk University, Yarmouk, Jordan
Dr. Saiful Islam Ansari, Assistant Professor, University of Tabuk, Saudi Arabia