Method and apparatus for maintaining uplink synchronization and reducing battery power consumption
First Claim
1. A method performed by a wireless transmit/receive unit (WTRU), the method comprising:
- receiving discontinuous reception (DRX) control information from a wireless network, the DRX control information indicating a time interval that the WTRU should monitor a downlink control channel;
receiving a control message on the downlink control channel while monitoring the downlink control channel according to the DRX control information, wherein the control message is associated with an identifier of the WTRU, the control message indicating that the WTRU should transmit a random access preamble to the wireless network;
transmitting the random access preamble to the wireless network in response to receiving the control message; and
receiving a timing adjustment command from the wireless network.
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Accused Products
Abstract
A Node-B sends a polling message to a wireless transmit/receive unit (WTRU). The WTRU sends an uplink synchronization burst in response to the polling message without contention. The Node-B estimates an uplink timing shift based on the synchronization burst and sends an uplink timing adjustment command to the WTRU. The WTRU then adjusts uplink timing based on the uplink timing adjustment command. Alternatively, the Node-B may send a scheduling message for uplink synchronization to the WTRU. The WTRU may send a synchronization burst based on the scheduling message. Alternatively, the WTRU may perform contention-based uplink synchronization after receiving a synchronization request from the Node-B. The WTRU may enter an idle state instead of performing a handover to a new cell when the WTRU moves to the new cell. A discontinuous reception (DRX) interval for the WTRU may be set based on activity of the WTRU.
64 Citations
20 Claims
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1. A method performed by a wireless transmit/receive unit (WTRU), the method comprising:
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receiving discontinuous reception (DRX) control information from a wireless network, the DRX control information indicating a time interval that the WTRU should monitor a downlink control channel; receiving a control message on the downlink control channel while monitoring the downlink control channel according to the DRX control information, wherein the control message is associated with an identifier of the WTRU, the control message indicating that the WTRU should transmit a random access preamble to the wireless network; transmitting the random access preamble to the wireless network in response to receiving the control message; and receiving a timing adjustment command from the wireless network. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8)
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9. A wireless transmit/receive unit (WTRU) comprising:
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a transceiver, and a processor coupled to the transceiver, the processor configured to; receive discontinuous reception (DRX) control information from a wireless network, the DRX control information indicating a time interval that the WTRU should monitor a downlink control channel; receive a control message on the downlink control channel while monitoring the downlink control channel according to the DRX control information, wherein the control message is associated with an identifier of the WTRU, the control message indicating that the WTRU should transmit a random access preamble to the wireless network; transmit the random access preamble to the wireless network in response to receiving the control message; and receive a timing adjustment command from the wireless network. - View Dependent Claims (10, 11, 12, 13, 14, 15, 16)
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17. A wireless transmit/receive unit (WTRU) comprising:
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a transceiver, and a processor coupled to the transceiver, the processor configured to; receive discontinuous reception (DRX) control information from a wireless network, the DRX control information indicating a time interval that the WTRU should monitor a downlink control channel; receive a control message on the downlink control channel while monitoring the downlink control channel according to the DRX control information, wherein the control message is associated with an identifier of the WTRU, the control message indicates that the WTRU should transmit a random access preamble to the wireless network, and the control message is indicative of a time and resource for the WTRU to transmit the random access preamble; transmit the random access preamble to the wireless network in response to receiving the control message; and receive a timing adjustment command from the wireless network. - View Dependent Claims (18, 19, 20)
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Specification