| 摘要 |
A method and apparatus enabling operation of a dual mode TDMA portable telephone unit is disclosed. The first mode of operation enables synchronous communication up to 75 kilometers. In the second mode of operation, the portable telephone unit operates according to a frame structure enabling synchronization between the portable telephone unit and the base station for ranges greater than 75 kilometers. This increased range is achieved by moving the transmission timeslot within the frame structure of a TDMA transmission in the second mode to a later timeslot then in the frame structure of the first mode. |
