Apparatus and method for alleviating barred access in mobile communication system

1. A user equipment for alleviating barred access while reselecting from a first cell to a second cell in a mobile communication system, comprising:

a wireless module receiving system information broadcasted in the first cell;

a storage unit storing the system information; and

a controller configured to perform the following:

reselecting the user equipment from the first cell to the second cell according to a reselection criterion based on signals from the first cell and the second cell received by the wireless module;

determining whether a first barred access timer is running for indicating an access of a first service is barred in the first cell, in response to reselecting from the first cell to the second cell;

stopping the first barred access timer and informing upper layers of a radio resource control (RRC) protocol about the access of the first service is allowed in response of that the first barred access timer is running;

determining whether a second barred access timer is running for indicating an access of a second service is barred in the first cell, in response to reselecting from the first cell to the second cell; and

stopping the second barred access timer and informing the upper layers of the RRC protocol about the access of the second service is allowed in response of that the second barred access timer is running,

wherein the first and the second barred access timer are chosen from any combination among barred access timers relating to the service of mobile terminating access, relating to the service of mobile originating call, and relating to the service of mobile originating signaling, and a first duration of the first barred access timer and a second duration of the second barred access timer are in a predetermined numerical order.

2. The user equipment of claim 1 , wherein the controller further determines whether a connection establishment guard timer is running for indicating an RRC connection establishment procedure is initiated, in response of that the first barred access timer is not running, and stopping the connection establishment guard timer, resetting a medium access control (MAC) protocol, and informing the upper layers of the RRC protocol that the RRC connection establishment procedure is failed, in response of that the connection establishment guard timer is running.

3. The user equipment of claim 1 , wherein the controller further determines whether the access of the first service is barred in the first cell according to the system information, and starts the first barred access timer in response of that the access of the first service is barred.

4. The user equipment of claim 1 , wherein the mobile communication system is an Evolved Universal Terrestrial Radio Access (E-UTRA) system.

5. A method for a user equipment to alleviate barred access while reselecting from a first cell to a second cell in a mobile communication system, comprising:

receiving system information broadcasted in the first cell;

storing the system information in a storage unit;

reselecting from the first cell to the second cell according to a reselection criterion based on signals from the first cell and the second cell;

determining whether a first barred access timer is running for indicating an access of a first service is barred in the first cell, in response to reselecting from the first cell to the second cell;

stopping the first barred access timer and informing upper layers of a radio resource control (RRC) protocol about the access of the first service is allowed, in response of that the first barred access timer is running;

determining whether a second barred access timer is running for indicating an access of a second service is barred in the first cell, in response to reselecting from the first cell to the second cell; and

stopping the second barred access timer and informing the upper layers of the RRC protocol about the access of the second service is allowed in response of that the second barred access timer is running,

wherein the first and the second barred access timer are chosen from any combination among barred access timers relating to the service of mobile terminating access, relating to the service of mobile originating call, and relating to the service of mobile originating signaling, and a first duration of the first barred access timer and a second duration of the second barred access timer are in a predetermined numerical order.

6. The method of claim 5 , further comprising determining whether a connection establishment guard timer is running for indicating an RRC connection establishment procedure is initiated, in response of that the first barred access timer is not running, and stopping the connection establishment guard timer, resetting a medium access control (MAC) protocol, and informing the upper layers of the RRC protocol that the RRC connection establishment procedure is failed in response of that the connection establishment guard timer is running.

7. The method of claim 5 , further comprising determining whether the access of the first service is barred in the first cell according to the system information, and starting the first barred access timer in response of that the access of the first service is barred.

8. The method of claim 5 , wherein the mobile communication system is an E-UTRA system.

9. A chipset for a user equipment to alleviate barred access while reselecting from a first cell to a second cell in a mobile communication system, comprising:

a storage unit storing system information broadcasted in the first cell; and

a controller configured to perform the following:

reselecting from the first cell to the second cell according to a reselection criterion based on signals from the first cell and the second cell;

determining whether a first barred access timer is running for indicating an access of a first service is barred in the first cell, in response to reselecting from the first cell to the second cell;

stopping the first barred access timer and informing upper layers of a radio resource control (RRC) protocol about the access of the first service is allowed in response of that the first barred access timer is running;

determining whether a second barred access timer is running for indicating an access of a second service is barred in the first cell, in response to reselecting from the first cell to the second cell; and

stopping the second barred access timer and informing the upper layers of the RRC protocol about the access of the second service is allowed in response of that the second barred access timer is running,

wherein the first and the second barred access timer are chosen from any combination among barred access timers relating to the service of mobile terminating access, relating to the service of mobile originating call, and relating to the service of mobile originating signaling, and a first duration of the first barred access timer and a second duration of the second barred access timer are in a predetermined numerical order.

10. The chipset of claim 9 , wherein the controller further determines whether a connection establishment guard timer is running for indicating an RRC connection establishment procedure is initiated, in response of that the first barred access timer is not running, and stopping the connection establishment guard timer, resetting a medium access control (MAC) protocol, and informing the upper layers of the RRC protocol that the RRC connection establishment procedure is failed, in response of that the connection establishment guard timer is running.

11. The chipset of claim 9 , wherein the controller further determines whether the access of the first service is barred in the first cell according to the system information, and starts the first barred access timer in response of that the access of the first service is barred.

12. The chipset of claim 9 , wherein the mobile communication system is an E-UTRA system.