Abstract:
When a wireless transmit receive unit (WTRU) is using a reduced dedicated physical control channel (DPCCH) frame, the WTRU may periodically send a normal DPCCH frame. The WTRU may periodically increase the transmit power or send a normal DPCCH frame if there is a transmit power control (TPC) error or a downlink quality is below a threshold. When the WTRU implements DPCCH transmission gating, the WTRU may set a gating period based on the number of received TPC commands. The WTRU or Node-B may restore to a normal mode, if the link quality is below a threshold. The WTRU may periodically increase a transmit power. When a reduced signal-to-interference ratio (SIR) target is used for TPC, the WTRU may increase a transmit power, if the downlink power is not responsive. The WTRU or the Node-B may restore a normal SIR target if the link quality is below a threshold.
Abstract:
Described herein are methods and apparatus related to wireless relay communications. An example architecture for relay communications may include a base station and a number of "Helper WTRUs" (H WTRUs) and "Terminal WTRUs" (T-WTRUs). Communication between the base station and a T-WTRU may take place via crosslink (XL) between an H-WTRU and the T-WTRU. Communication on the XL make be performed using a number of different coding and beamforming techniques. Additionally, measurement reporting may be configured on the XL, and the base station may perform power control on the XL.
Abstract:
A method and apparatus for establishing peer-to-peer communication and performing forwarding under the control of a cellular network are described. A seeking wireless transmit/receive unit (WTRU) may receive a timing signal from at least one discoverable WTRU controlled by a base station. The seeking WTRU may estimate the quality of a radio link (i.e., path loss) between the seeking WTRU and the discoverable WTRU, and determine, (e.g., based on a threshold established by the base station), whether or not to report the estimated radio link quality to a base station that controls the discoverable WTRU. The power of the timing signal may be ramped up in predetermined steps such that the transmission power at any given time is known and may be used by the seeking WTRU for estimating the radio link quality. The timing signal may include at least one of a primary preamble or a secondary preamble.
Abstract:
A base station (BS) may be configured to assist in the detection of a random access (RA) request failure and in clued an antenna configured to receive a RA request; a processor configured to decode the RA request; and a transmitter configured to transmit an aggregate RA response message comprising one or more RA responses that respond to one or more received and decoded RA requests.
Abstract:
A method and apparatus for cooperative relaying in wireless communications is provided. An efficient and simplified relay scheme is disclosed that transitions between different modes on a per packet basis using scheduling information or switching information included in the packet, without requiring link reconfiguration. The cooperative relay scheme benefits further from the use of cooperative relaying protocols that emphasize centralized scheduling. One protocol emphasizes physical layer cooperation via synchronized transmissions and distributed space-time coding and the other protocol emphasizes medium access control (MAC) layer cooperation using different MAC flows or messages.
Abstract:
A method and an apparatus for sending a signal on a contentious feedback channel for a downlink shared service and for estimating a number of wireless transmit/receive units (WTRUs) are disclosed. When a transmission criterion associated with a physical random access feedback channel (P-RAFCH) is satisfied, a physical resource is randomly selected among a plurality of physical resources assigned for the P-RAFCH and a pre- configured signal is sent using the selected physical resource. A Node-B receives the pre-configured signal from a plurality of WTRUs and calculates a number of the WTRUs based on a number of used physical resources. The transmission criterion is at least one of successful reception of a data packet on a downlink physical channel, successful reception of a data block on a data service, reception of a signaling command, occurrence of a measurement event, and failure to receive a transmission after a specified number of times.
Abstract:
A method and apparatus are used in cooperative relays with incremental redundancy (IR) and distributed spatial multiplexing. A wireless transmit/receive unit (WTRU) may listen to the base station (BS) transmission during Phase 1 of the communication, and use cooperation between a relay station (RS) and the BS for the data transmission during Phase 2 to improve performance. During Phase 2, both the BS and the RS may transmit data to the WTRU, using either distributed Space Time Block Codes/Space Frequency Block Codes (STBC/SFBC) or distributed spatial multiplexing.
Abstract:
A method and apparatus for signaling in a wireless transmit receive unit (WTRU). The method includes the WTRU receiving a value of a maximum number of retransmissions and retransmitting data in a plurality of hybrid automatic retransmission request (HARQ) processes limited by the value of a maximum number of retransmission. The WTRU is configured to receive a cell-specific, fixed or absolute grant on a broadcast channel.
Abstract:
A method and apparatus for signaling in a wireless transmit receive unit (WTRU). The method includes the WTRU receiving a value of a maximum number of retransmissions and retransmitting data in a plurality of hybrid automatic retransmission request (HARQ) processes limited by the value of a maximum number of retransmission. The WTRU is configured to receive a cell-specific, fixed or absolute grant on a broadcast channel.
Abstract:
A method and apparatus for No-TX mode for a wireless transmit/receive unit (WTRU) and Node B that suspends the transmission of power control updates and associated signaling over dedicated uplink and downlink channels. Triggers and signals between the WTRU and Node B activate and disable No-TX mode. A radio link is re-established to resume data transmission when No-TX mode is disabled, and data may also be transmitted during defined transmission opportunities while in No-TX mode.