Direct conversion transceiver design for compact low-cost portable mobile radio terminals

Abstract

A prototype direct conversion transceiver for portable mobile radio terminals has been developed and is under evaluation. Test results are presented showing the performance of this transceiver to be equivalent to (and in some cases better than) that of existing systems. The transmitter and receiver are described, and the receiver fading performance is examined. The results presented show that a direct conversion transceiver system can be made to work at both VHF and UHF. The improved channel characteristics facilitated by digital channel filtering make this configuration particularly suited to data transmission. In addition, the integration potential of all the system components is important for the concept of a 'personal communicator'.