Abstract: Embodiments of the invention provide a method to efficiently enable Network MIMO for use in the downlink direction. An association is established between a primary NodeB in a first cell and a secondary NodeB in an adjacent second cell. A set of downlink transmission resources is reserved for use by both the primary NodeB and the secondary NodeB. A transport block is transmitted from the secondary NodeB simultaneously with the primary NodeB to a user equipment (UE) near the edge of the first cell in response to a schedule provided by the primary NodeB. A time instance of the reserved transmission resources is released by the secondary NodeB when no simultaneous transmission of a transport block is scheduled within a minimum time.

Abstract: A coordinated multipoint transmitter is for use with a multiple antenna super-cell and includes primary and secondary base stations jointly connected via an X2 interface link, wherein the primary base station provides a transmission directive corresponding to an X2 interface protocol over the X2 interface link to the secondary base station for a joint transmission from the primary and secondary base stations.

Abstract: A wireless transmit/receive unit (WTRU) (152) in a wireless communications system includes a transceiver (153) for transmitting and receiving data from a plurality of base stations (154, 156, 357) and a controller (151) communicatively coupled to the transceiver (153) and configured to adjust an operation mode of the transceiver (153). In the WTRU (152), adjusting comprises configuring the transceiver (153) to begin a radio link handover procedure responsive to receiving a handover (HO) command from a first of the plurality of base stations (154, 156, 357) over a first communications link, specifying a first time, and reconfiguring the transceiver (153) to begin a radio link interruption procedure responsive to an expiry of the first time prior to completion of the radio link handover procedure. In the WTRU (152), the radio link interruption procedure first attempts to re-establish the first communications link.

Abstract: This invention employs an inherent tradeoff in a radio bearer dependent data handling method for intra-E-UTRA handoffs. For user equipment using real time data, the source node forwards to the target node not yet acknowledged real time service data units and disconnects. This makes the handoff latency short at the expense of data traffic between nodes. For user equipment not needing real time data, the source node continues to receive user equipment acknowledgements during a time out period and only forwards service data units acknowledged during the time out period. This reduces X2 interface traffic between the source and target nodes but extends the handoff latency.