Abstract: A wireless transmit/receive unit (WTRU) is configured to receive a WTRU-specific configuration of WTRU-specific sounding reference signal (SRS) subframes for performing SRS transmissions. The WTRU is configured to receive a trigger in a subframe to transmit a first SRS. The WTRU is configured to select a first subframe. The WTRU is configured to determine that a maximum power would be exceeded in a symbol in the selected first subframe. The WTRU is configured to, on a condition that transmission of at least one other SRS would at least partially overlap in the symbol in the selected first subframe, scale transmission powers of the first SRS and the at least one other SRS equally to comply with the maximum power. The WTRU is configured to transmit, in accordance with the scaled transmission powers, the first SRS in the selected subframe and the at least one other SRS.

Abstract: Disclosed is method and apparatus for operating a wireless network, the wireless network including a first eNB and a second eNB, including establishing an X2 interface between the first eNB and the second eNB and exchanging parameters between the first eNB and the second eNB via the X2 interface.

Abstract: A method and apparatus for multiple radio access technology (multi-RAT) access mode operation for a wireless transmit/receive unit (WTRU) are disclosed. A WTRU and a network may enable a multi-RAT access mode of operation based on at least one of WTRU subscription, a service agreement of the WTRU, a roaming status of the WTRU, a selected access point name (APN), an Internet protocol (IP) flow class, a subscriber profile identity for the WTRU, requested quality of service, or a proximity indication indicating proximity to a cell supporting multi-RAT access mode. The WTRU may send a capability indication of support of multi-RAT access to a network, wherein the multi-RAT access mode is enabled based on the capability indication. A partial handover of bearers may be performed. In performing the handover, the target cell is determined based on a priority rule.

Abstract: A method and apparatus for reducing handover time includes a wireless transmit receive unit receiving cell specific information in a downlink signal. The downlink signal is one of a set of signals included in a handover process.

Abstract: A method and apparatus for uplink sounding reference signals (SRS) transmissions are disclosed. A WTRU-specific configuration of WTRU-specific SRS subframes for performing SRS transmissions is received. A trigger is received in a subframe from a base station to transmit a first SRS. A first subframe is selected after the subframe in which the trigger is received which is both a WTRU-specific subframe and at least four subframes after the subframe in which the trigger is received. A determination if a maximum power is exceeded in a symbol in the selected first subframe is made. On a condition that the maximum power is not exceeded in the symbol in the selected first subframe, the first SRS is transmitted in the selected first subframe.

Abstract: Methods and apparatuses are disclosed for a wireless transmit/receive unit (WTRU) to perform a multi-radio access technology (RAT) access (MRA) operation. The apparatus may include a WTRU comprising a transceiver and a processor configured to send a non-access stratum (NAS) access request message to a network node using a first radio access technology (RAT). The message may indicate that the WTRU can connect to both a network node using the first RAT and a network node using a second RAT. The transceiver may be configured to receive a NAS accept message and a message comprising configuration information for the second RAT. The transceiver and the processor may be further configured to connect to a network node using the second RAT based on the received configuration information and communicate with both the network node using the first RAT and the network node using the second RAT.

Abstract: A method and apparatus for supporting communication buffer status reports (BSRs) are disclosed. A wireless device may receive from an eNode-B a first indication indicating a logical channel group and at least one associated priority. The wireless device may produce a BSR associated with first data, which may include an indication associated with the logical channel group and an index indicating an amount of the first data. The wireless device may transmit the BSR to an eNode-B. Then, the wireless device may receive receives allocation information for transmission to a wireless transmit/receive unit (WTRU) group. Further, the wireless device may transmit at least a portion of the first data to the WTRU group over a logical channel in the logical channel group. Also, the BSR may further include a plurality of indications associated with a respective plurality of logical channel groups.

Abstract: A method and apparatus reports packet data control protocol (PDCP) status and PDCP resets in a wireless communication, using control PDUs that may have security protection applied by ciphering of the control PDUs. Reliability of the PDCP status and reset messages may be assured by acknowledgement according to an acknowledged mode or to an unacknowledged mode.

Abstract: A WTRU may send a registration message to a core network (CN) that is associated with a first cell of a first radio access technology (RAT) and a second cell of a second RAT. The WTRU may receive, on the first cell of the first RAT with a first radio resource control (RRC) protocol, a RRC reconfiguration message that includes information for communications with the second cell of the second RAT. The first cell of the first RAT may be utilized for mobility management and a second RRC protocol may be utilized with the second cell of the second RAT.

Abstract: A method and apparatus for multiple radio access technology (multi-RAT) access mode operation for a wireless transmit/receive unit (WTRU) are disclosed. A WTRU and a network may enable a multi-RAT access mode of operation based on at least one of WTRU subscription, a service agreement of the WTRU, a roaming status of the WTRU, a selected access point name (APN), an Internet protocol (IP) flow class, a subscriber profile identity for the WTRU, requested quality of service, or a proximity indication indicating proximity to a cell supporting multi-RAT access mode. The WTRU may send a capability indication of support of multi-RAT access to a network, wherein the multi-RAT access mode is enabled based on the capability indication. A partial handover of bearers may be performed. In performing the handover, the target cell is determined based on a priority rule.

Abstract: A method and apparatus for supporting communication buffer status reports (BSRs) are disclosed. A wireless device may transmit data to a wireless transmit/receive unit (WTRU) group, which may include a WTRU and further include its own respective at least one logical channel group. The wireless device may produce a BSR, which may include an indication associated with the logical channel group and an index indicating an amount of data for the logical channel group. The wireless device may transmit the BSR to an eNode-B. Then, the wireless device may receive receives allocation information for transmission to the WTRU group. Also, the BSR may further include a plurality of indications associated with a respective plurality of logical channel groups, and the plurality of logical channel groups may be grouped based on priority. The index may further include a total amount of data across all logical channels of the logical channel group.

Abstract: A method and apparatus reports packet data control protocol (PDCP) status and PDCP resets in a wireless communication, using control PDUs that may have security protection applied by ciphering of the control PDUs. Reliability of the PDCP status and reset messages may be assured by acknowledgement according to an acknowledged mode or to an unacknowledged mode.

Abstract: A method for reporting power headroom is disclosed. Power headroom may be reported across all carriers (wideband), for a specific carrier, or for a carrier group. The formula used to calculate the power headroom depends on whether the carrier (or a carrier in the carrier group) has a valid uplink grant. If the carrier or carrier group does not have a valid uplink grant, the power headroom may be calculated based on a reference grant. The power headroom is calculated by a wireless transmit/receive unit and is reported to an eNodeB.

Abstract: Disclosed is method and apparatus for operating a wireless network, the wireless network including a first eNB and a second eNB, including establishing an X2 interface between the first eNB and the second eNB and exchanging parameters between the first eNB and the second eNB via the X2 interface.

Abstract: A method for controlling discontinuous reception in a wireless transmit/receive unit includes defining a plurality of DRX levels, wherein each DRX level includes a respective DRX cycle length and transitioning between DRX levels based on a set of criteria. The transitioning may be triggered by implicit rules.

Abstract: Various apparatuses and procedures for applying cell reselection priorities in a wireless transmit/receive unit (WTRU) are described. A method includes receiving a message including first cell reselection priorities assigned to a first plurality of frequencies and a validity timer associated with the first cell reselection priorities, where the validity timer indicates a length of time the first cell reselection priorities are valid, starting the validly timer based on the received message, performing a cell reselection evaluation using the first cell reselection priorities, and, on a condition that the validity timer expires, deleting the first cell reselection priorities, applying second cell reselection priorities assigned to a second plurality of frequencies, and performing a cell reselection evaluation using the second cell reselection priorities.

Abstract: In an embodiment, a client proxy provides an operating-system-functions (OS-functions) interface to client applications. The client proxy and each of the client applications resides on a wireless transmit/receive unit (WTRU). The client proxy receives, via the OS-functions interface, respective registrations from each of a plurality of the client applications. Each respective registration indicates a respective keep-alive-message signaling rate for the corresponding registered client application. The client proxy determines an optimal signaling rate based on the respective keep-alive message signaling rates indicated by the respective registrations. The client proxy generates proxy keep-alive signaling messages that collectively convey keep-alive-message information on behalf of the registered client applications. The client proxy transmits the generated proxy keep-alive signaling messages to a network node at the determined optimal signaling rate.

Abstract: A method for reporting power headroom is disclosed. Power headroom may be reported across all carriers (wideband), for a specific carrier, or for a carrier group. The formula used to calculate the power headroom depends on whether the carrier (or a carrier in the carrier group) has a valid uplink grant. If the carrier or carrier group does not have a valid uplink grant, the power headroom may be calculated based on a reference grant. The power headroom is calculated by a wireless transmit/receive unit and is reported to an eNodeB.

Abstract: Methods and apparatus are described for monitoring for a radio link failure in a long term evolution-advanced (LTE-A) system operated with carrier aggregation. The methods include criteria for determining radio link failure, recovery events, and the actions that a wireless transmit/receive unit (WTRU) may take upon the occurrence of such events.

Abstract: A method for controlling discontinuous reception in a wireless transmit/receive unit includes defining a plurality of DRX levels, wherein each DRX level includes a respective DRX cycle length and transitioning between DRX levels based on a set of criteria. The transitioning may be triggered by implicit rules.