Stmicroelectronics (Beijing) R&d Company Ltd.

Stmicroelectronics R&d Co. Ltd. (Beijing)

Yanling Yao

Hongfei Zhu

Guobin Sun

Consideration of Quality of Service is taken into account during the establishment of a sleep cycle in a mobile station providing real-time services. Upon the mobile station's identification of a need for a real-time service to enter into sleep mode, a request conveying that need is sent to the base station. The base station replies with a start frame number and other sleep parameters. Thereafter the mobile station enters sleep mode comprising sleep intervals interleaved with listening intervals. To prevent transmission packets from being buffered at the mobile station for an excessive period of time due to attempts to transmit packets to the base station during a sleep interval, the length of the sleep interval is set so as not to exceed the maximum latency value reflecting the QoS of the real-time service negotiated during establishment of the real-time services.

Sleep mode control for real-time services in broadband wireless access communication systems

A mobile device includes a communications protocol stack including a MAC layer and TCP layer separated by an IP layer. A cross-layer coordination module parallel to the communications protocol stack is coupled to both the MAC layer and TCP layer. The MAC layer generates a message sent to the cross-layer coordination module indicating that the mobile device is about to engage in a communications handover from a first base station to a second base station. The cross-layer coordination module passes handover information to the TCP layer so as to inform the TCP layer of the communications handover. If the mobile device is operating as a TCP sender, the TCP layer freezes its connection and state during the communications handover. If the mobile device is operating as a TCP receiver, the TCP layer sends a TCP ACK message to a TCP sender having an advertised window size set to a zero value so as to cause the TCP sender to freeze a connection and state during communications handover.

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Beijing, China

Yanling Yao