Method and apparatus for encoding and decoding automatic radio indentification data

摘要

A radio communications system includes plural radios with each radio having a microprocessor, a modem, and corresponding automatic number identification (ANI) information as well as a predetermined pattern of tones or digital codes corresponding to a particular radio frequency channel stored in memory. For each transmission, the radio microprocessor encodes the corresponding radio identification data that provides the encoded radio identification data to the radio modem in parallel format. The radio modem converts the encoded identification data into a serial data stream at the same time that the microprocessor is generating the predetermined pattern of tones or digital codes. Thereafter, the generated pattern of tones or digital codes is combined with the serial data stream and simultaneously transmitted over the transmission radio frequency channel. The modem also assists the microprocessor in the reception of radio identification data while the microprocessor is detecting received channel guard information. Because the modem has a data transmission frequency which exceeds the transmission frequency of the ANI data, each bit of ANI data is represented using a particular binary pattern (or its complement) to simulate an output at the modem corresponding to an ANI signalling carrier frequency.