A chip set for the US digital cellular mobile

A chip set for the USDC mobile cellular phone is presented. This chip set is being developed to enable cellular phone manufacturers to efficiently implement the complex functions that are necessary for the proper functioning of the USDC. The chip set is based on digital signal processors and application-specific integrated circuits, performing a number of key functions in the mobile unit. Thus, it contains the VSELP vocoder, the echo canceler, the channel coder, and the modem. Each function and some of the major sub-functions are described. Also presented are the interconnections of the chip set with the voice interface with intermediate-frequency interface, and with the host controller. The chip set supports analog and digital cellular mobiles