Abstract: Techniques for communicating on multiple carriers in a wireless communication network are described. In an aspect, different transmit power levels may be used for different carriers to mitigate interference. A first base station may be assigned one or more carriers among multiple carriers available for communication. A second base station may be assigned one or more carriers not assigned to the first base station. Each base station may communicate on each assigned carrier at a first (e.g., full) transmit power level and may communicate on each unassigned carrier at a second (e.g., lower) transmit power level lower. The first and second base stations may belong in different power classes or support different association types. In another aspect, control information may be sent on a designated carrier to support communication on multiple carriers. In yet another aspect, a base station may broadcast bar information indicating the status of carriers.

Abstract: Techniques for supporting broadcast/multiple transmission to multiple terminals with feedback and rate adaptation are described. In an aspect, a combination of HARQ and at least one shared feedback channel may be used to support broadcast/multicast transmission. In one design, a base station may send at least one transmission of a packet to multiple terminals, one transmission at a time. The base station may receive feedback information (e.g., NAK) for the packet from the terminals on the shared feedback channel(s). The base station may determine whether to terminate the packet early and/or may select at least one transmission parameter for another packet based on the feedback information for the packet. In another aspect, a transport format for a broadcast/multicast transmission may be selected based on CQI information from terminals receiving the transmission. The terminals may send CQI information at a slow rate and/or only certain terminals may send CQI information.

Abstract: Techniques for transmitting and receiving data with spatial interference mitigation in a wireless network are described. In one design of transmitting data with spatial interference mitigation, a first station (e.g., a cell) may receive spatial feedback information (SFI) from a second station (e.g., an interfered UE) that is not communicating with the first station. The second station may also receive preceding information from a third station (e.g., a served UE). The first station may send a data transmission to the third station based on the preceding information and the SFI in order to reduce interference to the second station. In one design, the SFI may include spatial nulling information. The first station may send the data transmission based on the spatial nulling information to steer the data transmission in a direction away from the second station.

Abstract: Techniques for transmitting and receiving data with spatial interference mitigation in a wireless communication network are described. In one design, a cell may receive preceding information from a first user equipment (UE) communicating with the cell and spatial feedback information (SFI) from a second UE not communicating with the cell. The cell may select a preceding matrix based on the preceding information and the SFI. The preceding matrix may steer a transmission toward the first UE and away from the second UE. The cell may send a reference signal based on the preceding matrix, send a resource quality information (RQI) request to the first UE, receive RQI determined by the first UE based on the reference signal, and determine a modulation and coding scheme (MCS) based on the RQI. The cell may then send a data transmission to the first UE with the preceding matrix and in accordance with the MCS.

Abstract: Techniques for sending signaling messages in a wireless communication network are described. In an aspect, a signaling message (e.g., a reduce interference request) may be sent by mapping it to at least one specific subcarrier among a set of subcarriers reserved for sending the signaling message. The at least one subcarrier may be selected based on the message value. A signal may be sent on the at least one subcarrier in multiple symbol periods to convey the signaling message. In another aspect, a reduce interference request may be sent based on an orthogonal resource among orthogonal resources available for sending reduce interference requests. In one design, an orthogonal sequence may be selected based on the request and may be spread across a resource segment. In another design, the reduce interference request may be processed to obtain modulation symbols, and each modulation symbol may be spread across multiple subcarriers in one symbol period.

Abstract: Systems and methodologies are described that facilitate scheduling over multiple hops in a wireless communication network. Radio resources can be partitioned into sets of sub-frames that can be allocated statically and/or dynamically. Statically allocated radio resources can be reassigned over time based on the loading on each hop and/or throughput imbalance. In addition, dynamic assignment of sub-frames to each hop can be based on traffic or channel conditions. Moreover, the radio resources can be dynamically allocated in a distributed scheme, wherein a base station controls the scheduling of resources, or a centralized scheme, wherein a relay station controls the scheduling of resources. Furthermore the allocation of radio resources can be transparent or explicit. In the transparent case, the access terminal listens directly to the base station, and the relay station does not transmit control information, such as DL or UL assignments.

Abstract: Systems and methods of scheduling sub-carriers in an OFDMA system in which a scheduler takes into account channel conditions experienced by the communication devices to optimize channel conditions. The scheduler can partition a set of sub-carriers spanning an operating bandwidth into a plurality of segments. The segments can include a plurality of global segments that each includes a distinct non-contiguous subset of the sub-carriers spanning substantially the entire operating bandwidth. One or more of the global segments can be further partitioned into a plurality of local segments that each has a bandwidth that is less than a channel coherence bandwidth. The scheduler determines channel characteristics experienced by each communication device via reporting or channel estimation, and allocates one or more segments to communication links for each device according to the channel characteristics.

Abstract: Systems and methods of scheduling sub-carriers in an OFDMA system in which a scheduler takes into account channel conditions experienced by the communication devices to optimize channel conditions. The scheduler can partition a set of sub-carriers spanning an operating bandwidth into a plurality of segments. The segments can include a plurality of global segments that each includes a distinct non-contiguous subset of the sub-carriers spanning substantially the entire operating bandwidth. One or more of the global segments can be further partitioned into a plurality of local segments that each has a bandwidth that is less than a channel coherence bandwidth. The scheduler determines channel characteristics experienced by each communication device via reporting or channel estimation, and allocates one or more segments to communication links for each device according to the channel characteristics.

Abstract: Techniques for selecting a serving base station for a terminal in a wireless communication network are described. In one design, multiple candidate base stations for the terminal may be identified, with each candidate base station being a candidate for selection as the serving base station for the terminal. The multiple candidate base stations may include base stations with different transmit power levels and/or may support interference mitigation. One of the multiple candidate base stations may be selected as the serving base station. In one design, the serving base station may be selected based on at least one metric for each candidate base station. The at least one metrics may be for pathloss, effective transmit power, effective geometry, projected data rate, control channel reliability, network utility, etc. The selected candidate base station may have a lower SINR than a highest SINR among the multiple candidate base stations.