Two way calling enhancement to the public CT2 system

Abstract

In the current implementation of the CT2 systems in Singapore. only handset initiated calls are allowed. This paper will describe a design to allow two-way calling for the CT2 system with minimal modification to the current CT2 infrastructure as well as the Public Switched Telephone Network (PSTN). The design makes use of centralized databases in the Home Location Register (HLR) and Visitor Location Register (VLR) to track the location of the handsets. The diagram of the CT2 two-way calling system is depicted in figure l. We also did a computer simulation of the proposed system to determine the potential area of congestion in the system.