The advanced mobile phone service (AMPS) system, an FM cellular radio system in the final stages of development, is described. A brief description of the system is followed by a discussion of the control algorithms which are basic to its operation. Finally, a status report is presented on the Chicago developmental system (an operational cellular system) and the cellular test bed in Newark, NJ (a field laboratory used to evaluate the radio performance of FM cellular systems with cells as small as 1.4-mi radius).