Investigation of Causes of Call Drops in GSM Network: A Case Study of Zain Nig. Ltd. in Benin City, Nigeria

Abstract

This research is an investigation of the causes of call drops in a GSM network in Benin City, Nigeria. Call drop is inability of call to connect and go through the network successfully. For a drop call the subscriber does not enter into a queue for potential assignment. In this work, a drive test was conducted over a period of three months (March, April and May 2010) in cells around Benin City area. The drive test was conducted with the use of test mobile. A test mobile is a kit comprising mobile phone, drive testing proprietary software called TERMS on a laptop computer and GPS (global positioning system). A total of twenty seven cells out of forty cells around Benin City area were discovered to have severe call drops leading to very poor network performance. The problems that caused the call drops were determined and corrected leading to high improvement in call performance.

Survey dataset on analysis of queues in some selected banks in Ogun State, Nigeria

“…See Refs. [2] , [4] , [5] , [6] . The confidence intervals for average service rate and average arrival rate can be estimated assuming the service time and arrival time are independent and identically distributed.…”

“… Queues are necessary if order is to be maintained in the society, but most queues in sub-Saharan countries constitute a menace and sometimes end in riot and mob actions. Hence the data can be useful for security agents responsible for maintaining law and order [1] , [2] . The data could be used by banking regulatory bodies in Nigeria.…”