Apparatus and method for uplink transmission in wireless communication system
AssigneeLG Electronics Inc.
InventorHee Chul Yoo
Life of this patent
Estimating the term…
Abstract
An apparatus and method for uplink transmission in a wireless communication system are provided. The method comprises detecting an expiry of a time alignment timer in a MAC (Medium Access Control) layer, the time alignment timer being used to control how long the UE is considered uplink time aligned, notifying a release of PUCCH (Physical Uplink Control Channel) resources from the MAC layer to a RRC (Radio Resource Control) layer when the expiry of the time alignment timer is detected and keeping a part of the PUCCH (Physical Uplink Control Channel) resources in the RRC layer.
Claims15
A method for uplink transmission in a wireless communication system, the method carried out by a user equipment (UE), the method comprising:
- receiving a time alignment command from a base station;
- starting a time alignment timer by applying the time alignment command so as to control how long the UE is considered uplink time aligned;
- detecting whether the time alignment timer has expired;
- when the time alignment timer has expired,
- notifying a release of control resources used for transmission of control signals from a Medium Access Control (MAC) layer to a Radio Resource Control (RRC) layer, and
- notifying a physical (PHY) layer by the MAC layer to suspend the control resources while the time alignment timer is not running;
- upon a receipt of the release notification at the RRC layer, performing a random access procedure;
- and
- resuming the control resources suspended in the PHY layer when the timer alignment timer is restarted.
A user equipment (UE), comprising:
- a radio frequency (RF) unit configured to receive and transmit radio signals;
- and
- a processor operatively connected to the RF unit, and configured to implement a radio interface protocol including a Medium Access Control (MAC) layer and a Radio Resource Control (RRC) layer,
- wherein the processor is further configured to:
- receive a time alignment command from a base station;
- start a time alignment timer by applying the time alignment command so as to control how long the UE is considered uplink time aligned;
- detect whether the time alignment timer has expired;
- when the time alignment timer has expired,
- notify a release of control resources used for transmission of control signals from the MAC layer to the RRC layer, and
- notify a physical (PHY) lager by the MAC layer to suspend the control resources while the time alignment timer is not running;
- upon a receipt of the release notification, perform a random access procedure;
- and
- resume the control resources suspended in the PHY layer when the timer alignment timer is restarted.
A method for maintaining, by a user equipment (UE), an uplink time alignment in a wireless communication system, the method comprising:
- receiving, from a base station, a time alignment command;
- starting a time alignment timer by applying the time alignment command, the time alignment timer being used to control how long the UE is considered uplink time aligned;
- detecting whether the time alignment timer is expired;
- when the time alignment timer is expired, notifying a release of control resources used for transmission of control signals from a medium access control (MAC) layer to a radio resource control (RRC) layer, and notifying a physical (PHY) layer by the MAC layer to suspend the control resources while the time alignment timer is not running;
- transmitting, to the base station, a random access preamble which is randomly selected from a set of random access preambles after the time alignment timer is expired;
- receiving, for the base station, a random access response as a response of the random access preamble, the random access response including a timing advance command;
- and
- restarting the time alignment timer by applying the timing advance command.
Dependencies are inferred from the claim text.