Protocol for allocating upstream slots over a link in a point-to-multipoint communication system

Abstract

A system for controlling a contention state for a communication link between a base station controller and customer premises equipment in point-to-multipoint communication. The contention state is controlled using a state machine, which includes a grant pending absent state in which a unicast request slot is maintained open for use by the customer premises equipment. During the grant pending absent state, the customer premises equipment sends no upstream data to the base station controller but can use the unicast request slot to request a data slot for sending upstream data to the base station controller. In the grant pending state, the customer premises equipment preferably uses piggybacking to request grant of a next data slot while sending upstream data to the base station controller.

We claim: 
     
         1 . A customer premises equipment (CPE), comprising:
 a processor;   an antenna operable to send information using wireless communication techniques in a point-to-multipoint communication system, the CPE operable to communicate with a base station controller (BSC) over a communication link shared with other CPEs; and   a memory comprising instructions, the instructions executable by the processor to:
 transition from a grant pending state to a grant pending absent state once
 the CPE has transmitted upstream data to the BSC within a bandwidth specified by a bandwidth grant received from the BSC during the grant pending state and 
 the CPE has no pending bandwidth requests; 
 
 operate the CPE in the grant pending absent state wherein the CPE awaits arrival of data for transmission to the BSC and transmits, via the antenna, a non-contention bandwidth request to the BSC when the CPE receives data for transmission; 
 transition operation of the CPE from the grant pending absent state to the grant pending state subsequent to and in consequence of a subsequent bandwidth grant received at the CPE; and 
 transition operation of the CPE from the grant pending absent state to an idle state if the CPE does not transmit any non-contention bandwidth request to the BSC during a timeout period.