Patent ID: 9451419
Filing Date: 2016-09-20
CPC Classification: H04W

Claim Text:
1. A method of operating a subscriber unit to seamlessly switch between a trunked mode operation and a direct mode operation, the method comprising at the subscriber unit: maintaining attributes associated with a first communication channel and a second communication channel, wherein the first communication channel is used by the subscriber unit to communicate in trunked mode operation via at least one base station and the second communication channel is used by the subscriber unit to communicate in direct mode operation with at least one direct mode gateway station that is configured to relay communications between the first communication channel and the second communication channel, wherein the attributes associated with the first communication channel used by the subscriber unit to communicate in trunked mode operation is received from the at least one direct mode gateway station when communicating using the second communication channel in the direct mode operation and the attributes associated with the second communication channel used by the subscriber unit to communicate in the direct mode operation is received from the at least one base station when communicating using the first communication channel in the trunked mode operation; determining, when communicating using the first communication channel in trunked mode operation, whether the signal quality on the first communication channel is below a predetermined threshold, and in response to determining that the signal quality on the first communication channel is below the predetermined threshold, using the attributes associated with the second communication channel and received from the at least one base station over the first communication channel to automatically switch to the direct mode operation for communicating on the second communication channel; and determining, when communicating using the second communication channel in direct mode operation, whether the signal quality on the second communication channel is below a predetermined threshold, and in response to determining that the signal quality on the second communication channel is below the predetermined threshold, using the attributes associated with the first communication channel and received from the at least one direct mode gateway over the second communication channel to automatically switch to the trunked mode operation for communicating on the first communication channel.