Advanced Mobile Phone Service: A Subscriber Set for the Equipment Test

The AMPS mobile telephone subscriber set interfaces the mobile telephone customer with the switched telephone network via a twoway UHF radio path that connects the subscriber's automobile with a cell site. Voice signals, which are frequency-multiplexed with line supervision signals or time-multiplexed with 10-kb/s control signals, flow over this radio path. The mobile telephone subscriber set consists of three basic elements: a control unit, a transceiver, and a logic unit. The control unit is the subscriber's primary contact with the AMPS system and is mounted in the passenger compartment of the automobile, within easy reach of the driver and front seat passengers. It serves as the required physical interface between the customer and the telephone network via a handset for acoustical interface, a pushbutton keypad for entering commands into the telephone network, and signal lamps and/or acoustic tones for customer alerting. The transceiver unit, generally mounted in the trunk compartment 123