Abstract: Method and apparatus are disclosed for optimizing Random Access Channel (RACH) transmissions from wireless transmit/receive units (WTRUs) for multiple transmissions. A WTRU may initiate uplink transmission for a random access procedure using a configured time resource such that the uplink resources may be time shared by a plurality of WTRUs. The transmission time may be calculated on an absolute or relative basis. A backoff time may be applied before starting the uplink transmission. The backoff time may be WTRU-specific, WTRU group-specific, specified per access class and may be determined based on a priority basis. A scaling factor may be applied to the backoff time. A contention free allocation method may be used to determine the appropriate resource. The data may be transmitted with and without a preamble. The WTRUs may include machine type communication devices and may be grouped in accordance with a number of factors or characteristics.

Abstract: Systems, methods, and instrumentalities to optimize procedures relating to machine type communication devices. Individual UEs may be grouped together in order to optimize procedures relating to members of the group. For example, a group of UE devices may be predefined or a group may be configured by a network associated with the UEs. One or more of the members of the group may be designated as a special UE or a master UE. The special UE or master UE may perform an action on behalf of one or more members of the group.

Abstract: Systems, methods, and instrumentalities to optimize procedures relating to machine type communication devices. Individual UEs may be grouped together in order to optimize procedures relating to members of the group. For example, a group of UE devices may be predefined or a group may be configured by a network associated with the UEs. One or more of the members of the group may be designated as a special UE or a master UE. The special UE or master UE may perform an action on behalf of one or more members of the group.

Abstract: Maintaining time alignment with multiple carriers is contemplated. A group of uplink carriers (UL CC sets) that operate with a single Timing Advance (TA) may be determined, and a TA value may be applied to a specific UL CC set. A wireless transmit/receive unit's (WTRU) capability of using multiple TAs may define a group index of a few bits for each UL CC set. A TA Command received in a Random Access Response message may be used to apply the TA value to each UL carrier of the UL CC set. The WTRU may determine which UL CC set the TA value applies to based on which DL carrier the command was transmitted from. The WTRU may determine which UL CC set the TA value applies to based on the Group Index being explicitly provided in the command. The WTRU may release multi-CC configurations upon Time Alignment Timer (TAT) expiry.

Abstract: Maintaining time alignment with multiple carriers is contemplated. A group of uplink carriers (UL CC sets) that operate with a single Timing Advance (TA) may be determined, and a TA value may be applied to a specific UL CC set. A wireless transmit/receive unit's (WTRU) capability of using multiple TAs may define a group index of a few bits for each UL CC set. A TA Command received in a Random Access Response message may be used to apply the TA value to each UL carrier of the UL CC set. The WTRU may determine which UL CC set the TA value applies to based on which DL carrier the command was transmitted from. The WTRU may determine which UL CC set the TA value applies to based on the Group Index being explicitly provided in the command. The WTRU may release multi-CC configurations upon Time Alignment Timer (TAT) expiry.

Abstract: Systems, methods, and instrumentalities to optimize procedures relating to machine type communication devices. Individual UEs may be grouped together in order to optimize procedures relating to members of the group. For example, a group of UE devices may be predefined or a group may be configured by a network associated with the UEs. One or more of the members of the group may be designated as a special UE or a master UE. The special UE or master UE may perform an action on behalf of one or more members of the group.

Abstract: Enhanced protocols and devices may be used to alleviate loss of spectrum efficiency in wideband transmission. The protocols may implement a wideband transmission opportunity (TXOP) truncation where one or more of the channels involved in communication over the wideband are released. In one scenario, a wireless transmit/receive unit (WTRU) may obtain a TXOP for a 2 MHz bandwidth mode frame transmission with another device capable of operating in a 2 MHz bandwidth mode and a 1 MHz bandwidth mode. The WTRU may conduct a request-to-send (RTS)/clear-to-send (CTS) frame exchange in the second bandwidth mode, and truncate the TXOP by transmitting a contention free (CF)-End frame in the first and second bandwidth modes. In another scenario, an AP may obtain a TXOP for a 2 MHz bandwidth mode frame transmission with a WTRU capable of both 2 MHz and 1 MHz bandwidth modes.

Abstract: Systems and methods are provided for receiving data from multiple cells. A wireless transmit and receive unit (WTRU) may receive data from cells in a multi-point set that includes a primary serving cell and one or more assisting serving cells. The WTRU measures the quality of cells in the multipoint set as well as neighboring cells. Based on the cell quality, the WTRU triggers a reporting event, such cell adding event, cell removal event, or cell replacement event, and sends a measurement report to the network. The WTRU receives an indication of a change to the multi-point set from the network, and modifies the multi-point set accordingly.

Abstract: Methods and apparatus are provided for performing group-based machine-to-machine (M2M) communication. Machine-type communication (MTC) wireless transmit/receive units (WTRUs) may operate in M2M groups. A group of MTC WTRUs may be paged collectively as a group. An MTC WTRU may store an individual international mobile subscriber identity (IMSI) associated with the MTC WTRU, and a group-based IMSI associated with the MTC group that the MTC WTRU belongs to. The MTC WTRU may use one or both IMSIs to receive paging messages. When the MTC WTRU receives a paging message, the MTC WTRU may compare a recipient IMSI contained in the paging message to the individual IMSI and the group-based IMSI. If the recipient IMSI matches the individual IMSI and the group-based IMSI, the MTC WTRU may proceed to process the paging message.

Abstract: Maintaining time alignment with multiple carriers is contemplated. A group of uplink carriers (UL CC sets) that operate with a single Timing Advance (TA) may be determined, and a TA value may be applied to a specific UL CC set. A wireless transmit/receive unit's (WTRU) capability of using multiple TAs may define a group index of a few bits for each UL CC set. A TA Command received in a Random Access Response message may be used to apply the TA value to each UL carrier of the UL CC set. The WTRU may determine which UL CC set the TA value applies to based on which DL carrier the command was transmitted from. The WTRU may determine which UL CC set the TA value applies to based on the Group Index being explicitly provided in the command. The WTRU may release multi-CC configurations upon Time Alignment Timer (TAT) expiry.

Abstract: Method and apparatus are disclosed for optimizing Random Access Channel (RACH) transmissions from wireless transmit/receive units (WTRUs) for multiple transmissions. A WTRU may initiate uplink transmission for a random access procedure using a configured time resource such that the uplink resources may be time shared by a plurality of WTRUs. The transmission time may be calculated on an absolute or relative basis. A backoff time may be applied before starting the uplink transmission. The backoff time may be WTRU-specific, WTRU group-specific, specified per access class and may be determined based on a priority basis. A scaling factor may be applied to the backoff time. A contention free allocation method may be used to determine the appropriate resource. The data may be transmitted with and without a preamble. The WTRUs may include machine type communication devices and may be grouped in accordance with a number of factors or characteristics.

Abstract: A method for performing load balancing by a wireless transmit/receive unit includes evaluating a current cell load value and on a condition that the current cell load value is greater than a predetermined threshold, performing load balancing by barring the current cell.