Patent ID: 6473420
Filing Date: 2002-10-29
Classification: H04B,H04J,H04W

Abstract:
In a communication system having a hub radio and at least one remote radio, where the hub radio operates at a first frequency f0 and includes a modem with a tolerance range of synchronization of Â±&Dgr;f1, a method of synchronizing the remote radio with the hub radio comprising the steps of:a) transmitting a first ranging signal from the remote radio to the hub radio; b) receiving the ranging signal at the hub radio; c) evaluating the ranging signal received at the hub and transmitting a synchronizing signal from the hub radio to the remote radio if the hub radio can not synchronize with the received ranging signal after a predetermined period of time; d) receiving the synchronizing signal from the hub radio at the remote radio and adjusting the frequency of transmission of the remote radio to a predetermined frequency outside the tolerance range of the modem from f0; e) transmitting a ranging signal from the remote radio at the adjusted frequency to the hub radio; f) evaluating the most recently received ranging signal at the hub radio and transmitting a synchronizing signal from the hub radio to the remote radio if the hub radio can not synchronize with the ranging signal after a predetermined period of time; g) receiving the most recently received synchronizing signal from the hub radio at the remote radio and adjusting the frequency of transmission of the remote radio by a predetermined frequency correction; h) transmitting a ranging signal from the remote signal at the adjusted frequency; and i) repeating steps f)-h) until the hub radio can synchronize with the received ranging signal.