Planning a Cellular System
Dr. Md. Mostafizur Rahman Professor
Department of Electronics and Communication Engineering Khulna University of Engineering & Technology (KUET)
How to Start Planning
To create a good Plan we have to determine 2 elements :
Rules Regulations
Market Situations
There are 3 tasks to be handled by the marketing department.
Prediction of gross income
Understanding the Competitors
Decision of Geographic coverage
The Engineer’s role for implementing a Mobile Station
Initiating a cellular mobile service in a given area by creating a plan that uses a minimum number of cell sites to cover the whole area.
Checking the areas that marketing indicated were important revenue area.
The number of radios (no of voice channels) required to handle the traffic load at busy hours should be determined.
Studying the interference problems, such as co-channel and adjacent channel interference and the intermodulation products generated at the cell sites and finding ways to reduce them.
Studying the blocking probability of each cell at each cell site and trying to minimize it.
Planning to absorb more customers.
Radio performance including both quality of the control transmission path quality of the voice transmission path.
The measure of transmission performance is the RF signal to impairment ratio S/(I+N)
Outline of the Engineering Procedure
Begin with Coverage Grid
Performance Service Criteria Tests
Diagnose Reasons for S/I Failure
Determine Cures, Develop New Configuration
Stop
Diagnostic and Problem Solving Procedures for System Configuration
System Configuration (Cellular Grid) – Cell Site Location, Transmitter Power, Antenna Types, Antenna Heights.
A mean S/(I+N) of >= 17 dB, over 90% of the services area.
A mean S/(I+N) of >= 5 dB, over 99% of the services area
Mobile Cellular Telecommunications (Chapter 01) – W C Y Lee
Wireless and Personal Communications (Chapter 13)– Garg & Wilkes (GW)
