Introduction

Cellular and personal communication service (PCS) mobile radio system are wireless communication systems that provide for voice and data communication throughout a wide geographic area. The key to the success for cellular systems is their flexibility to increase the number of channels to service the ever-increasing capacity demands of a growing customer base.

Figure 4.1 shows a basic cellular system. The cellular network connects mobile radios to each other or the public switched telephone network (PSTN) by using radio towers (base stations) that are connected to a mobile switching center (MSC). The mobile switching center can transfer calls to the PSTN.

Figure 4.1: Cellular System

When linked together to cover an entire metro area, the radio coverage areas (called cells) form a cellular structure resembling that of a honey comb. The cellular systems are designed to have overlap at each cell border to enable a hand-off from one cell to the next. As a customer (called a subscriber) moves through a cellular or a Personal Communications Service (PCS) system, the mobile switching center (MSC) coordinates and transfers calls from one cell to another and maintains call continuity.