Abstract: Techniques for managing interference in a wireless network are described. In an aspect, reduce interference requests and interference indicators may be used for interference management to enable operation in scenarios with dominant interferers. In one design, a terminal may receive a reduce interference request from a first base station requesting lower interference on specified time-frequency resources. The terminal may also receive an interference indicator conveying the interference observed by a second base station. The terminal may determine its transmit power based on the reduce interference request and the interference indicator. For example, the terminal may determine an initial transmit power based on the reduce interference request (or the interference indicator) and may adjust the initial transmit power based on the interference indicator (or the reduce interference request) to obtain its transmit power. The terminal may transmit data to a serving base station at the determined transmit power.

Abstract: Techniques for transmitting null pilots to support interference estimation in a wireless network are described. A null pilot is non-transmission on designated time-frequency resources by a cell or a cluster of cells supporting cooperative transmission to a UE. The received power of the null pilot from the cell or cluster of cells may be indicative of interference from other cells. In one design, a cell in the cluster may determine resources for sending a null pilot by the cell. The cell may transmit the null pilot (i.e., send no transmissions) on the resources to allow UEs to estimate out-of-cluster interference. Some or all cells in the cluster may transmit null pilots on the same resources. The cell may receive interference and channel information from the UE and may send data transmission to the UE based on the interference and/or channel information. Remaining cells in the cluster may reduce interference to the UE.

Abstract: Providing for improved access communication for wireless systems is described herein. By way of example, wireless devices can employ wireless resource re-use in selecting a subset of access communication resources, to mitigate interference on uplink access requests. Re-use can be based on current network conditions, or on a type of base station facilitating the wireless communication. In some aspects, planned resource re-use can be facilitated by an access terminal. The access terminal requests neighboring or interfering network access points to reserve a set of resources for a serving access point. Reserved resources can be conveyed to the serving access point with an uplink access probe, to further mitigate interference.

Abstract: Systems and methodologies are described that facilitate indicating a dominant interferer to a target serving base station in a wireless communication environment. A mobile device can detect presence or absence of a dominant interferer. Further, an access probe that includes information related to the presence or absence of the dominant interferer can be generated. For example, the information can be included in a payload of the access probe as an explicit flag, an explicit indication of an interference level, a Channel Quality Indicator (CQI) value (e.g., reserved versus non-reserved, . . . ), etc. Moreover, the access probe can be transmitted to the target serving base station to initiate an access procedure. The target serving base station can select a time-frequency resource to be utilized for a responsive downlink transmission (e.g. access grant signal, subsequent access related message, . . . ) as a function of the information included in the access probe.

Abstract: A reference signal and handoff management (RSHM) program executing on a mobile device detects reference signals, allocates them into groups, and performs handoffs between synchronous and asynchronous sectors. Sectors are allocated to an active group. Sectors from the active group that satisfy a channel quality constraint are allocated to a second group. Sectors from the second group that satisfy a link budget constraint are allocated to a third group. The RSHM program calculates a weighted characteristic of the forward and reverse links of sectors in the third group. The RSHM program performs handoffs from current serving sectors to sectors having the largest weighted characteristic that exceeds the weighted characteristic of the current serving sector by an hysteresis amount.

Abstract: Techniques for transmitting data with short-term interference mitigation in a wireless communication system are described. In one design, a first station (e.g., a base station or a terminal) may receive a message sent by a second station to request reduction of interference on at least one resource. In response to receiving the message, the first station may determine a first transmit power level to use for the at least one resource based on one or more factors such as a priority metric sent in the message, the buffer size at the first station, etc. The first station may send a power decision pilot on the at least one resource at a second transmit power level determined based on the first transmit power level.

Abstract: Techniques for transmitting data with short-term interference mitigation in a wireless communication system are described. In one design, a first station (e.g., a base station or a terminal) may send a first message to at least one interfering station to request reduction of interference on at least one resource. The first station may send the first message in anticipation of receiving data on the at least one resource. An interfering station may receive the first message from the first station and may reduce interference on the at least one resource by reducing its transmit power and/or by steering its power in a direction different from the first station. The first station may thereafter receive data from a second station on the at least one resource. The techniques may be used for data transmission on the forward and reverse links.

Abstract: Techniques for transmitting data with short-term interference mitigation in a wireless communication system are described. In one design, a serving base station may send a message to a terminal to trigger short-term interference mitigation. In response, the terminal may send a message to request at least one interfering base station to reduce interference on at least one resource. Each interfering base station may determine a transmit power level to be used for the at least one resource and may send a pilot at this transmit power level. The terminal may estimate the channel quality of the at least one resource based on at least one pilot received from the at least one interfering base station. The terminal may send information indicative of the estimated channel quality to the serving base station. The serving base station may send a data transmission on the at least one resource to the terminal.

Abstract: Systems and methodologies are described that facilitate mitigation of interference in a wireless communication environment. Terminals can utilize interference information provided by neighboring sectors to adjust transmit power and reduce interference. Access points can provide two sets or types of interference information. The first type can be transmitted over a large coverage area, requiring significant overhead and limiting the transmission rate. Access points can also provide a second set or type of interference information directed at smaller coverage area, such as an area proximate to the edge of the supported sector. This second type of interference information can be utilized by terminals that include the access point within their active set. The second set of interference information can be provided at a higher rate than the first set due to decreased overhead requirements. Terminals can utilize both sets of interference information to adjust transmit power.

Abstract: Systems and methodologies are described that facilitate reverse link power control on a traffic channel. Indications of other sector interference or other such interference levels can be broadcasted in a wireless communication. Further, power control related information can be included in assignments to mobile devices. Mobile device can utilize the information in the assignment to set a range for delta-based power control. Further, devices employ broadcasted interference indications to maintain and adjust delta values that enable power settings to be established on traffic channels. Moreover, mobile devices may provide feedback to facilitate future assignments.

Abstract: Techniques for transmitting data with hybrid automatic retransmission (HARQ) and interference mitigation are described. In one design, a transmitter processes a packet of data in accordance with a rate and sends at least one transmission of the packet to a receiver with HARQ. In one design, the transmitter sends a trigger message to the receiver to trigger the receiver to send a request to reduce interference to interfering station(s). The transmitter may send a first transmission of the packet (i) after the trigger message, e.g., in consecutive frames of a single HARQ interlace, or (ii) along with the trigger message in the same frame. The number of transmissions to send for the packet may be dependent on whether the interfering station(s) reduce interference to the receiver. The packet transmission may terminate early if interference mitigation is successful or may terminate late if interference mitigation is unsuccessful.

Abstract: Systems and methodologies are described that facilitate recovering from error due to false detection of completion signals at an access terminal. An access terminal specific request signal can be sent to a target base station to initiate handoff or semi-connected state exit. A completion signal can be transferred in response to the access terminal specific request signal. To mitigate errors stemming from false detection of the completion signal at the access terminal, forward link and reverse link confirmation signals can be transferred to confirm successful handoff or connected state re-entry completion. For example, the access terminal can determine handoff or re-entry to be successful when a forward link confirmation signal is detected prior to expiration of a timer. Moreover, the forward link and reverse link confirmation signals can each include more CRC bits as compared to a number of CRC bits included in the completion signal.

Abstract: Systems and methodologies are described that provide techniques for generating and utilizing reverse link feedback for interference management in a wireless communication system. Channel quality and/or interference data can be obtained by a terminal from a serving sector and one or more neighboring sectors, from which an interference-based headroom value can be computed that contains interference caused by the terminal to an allowable range. The interference-based headroom value can then be provided with power amplifier (PA) headroom feedback to the serving sector. Based on the provided feedback from the terminal, the serving sector can assign resources for use by the terminal in communication with the serving sector. Further, the serving sector may choose to honor or disregard a received interference-based power value based on quality of service and/or other system parameters.

Abstract: A apparatus and method for improved performance in radio telecommunications systems, and in particular multi-carrier code division multiple access (MC-CDMA) networks that employ pulse-shaping filters on the transmit side of a radio link. In order to more accurately transmit a radio signal bearing a symbol sequence, the modulated and spread information stream is upsampled using a technique that involves inserting zeros in the frequency domain. A corresponding downsampling procedure on the receive side permits reconstruction of the transmitted symbols. A new channel estimation algorithm may also be used, and the improved channel estimation advantageously employed to obtain more faithful symbol detection.

Abstract: Techniques for mitigating interference in a wireless communication system are described. In one design, a sector may determine multiple fast other sector interference (OSI) indications for multiple subzones, with each subzone corresponding to a different portion of the system bandwidth. At least one report may be generated for the multiple OSI indications, with each report including at least one OSI indication for at least one subzone. Each report may be encoded to obtain code bits, which may then be mapped to a sequence of modulation symbols. A sequence of modulation symbols of zero values may be generated for each report with all OSI indications in the report set to zero to indicate lack of high interference in the corresponding subzones. This allows a report to be transmitted with zero power in a likely scenario. A regular OSI indication may also be determined for the system bandwidth and transmitted.

Abstract: Techniques for transmitting pilot and traffic data are described. In one aspect, a terminal may scramble its pilot with a scrambling sequence generated based on a set of static and dynamic parameters. The static parameter(s) have fixed value for an entire communication session for the terminal. The dynamic parameter(s) have variable value during the communication session. The terminal may generate a scrambling sequence by hashing the set of parameters to obtain a seed and initializing a PN generator with the seed. The terminal may then generate the pilot based on the scrambling sequence. In another aspect, the terminal may use different scrambling sequences for pilot and traffic data. A first scrambling sequence may be generated based on a first set of parameters and used to generate the pilot. A second scrambling sequence may be generated based on a second set of parameters and used to scramble traffic data.

Abstract: Systems and methodologies are described that facilitate controlling reverse link power on a traffic channel. Assignments for reverse link communication can be yielded. Interference from mobile devices in neighboring sectors can be monitored and other sector interference (OSI) indications can be broadcasted. The OSI indications can be obtained by mobile devices to alter delta values employed for delta-based power control. Further, a maximum allowable amount of reduction of a delta value can be allocated per QoS class. Moreover, mobile devices can provide in-band and out-of-band feedback, which can be leveraged for future assignments.

Abstract: Systems and methodologies are described that facilitate mitigating effect of non-linear distortion from a power amplifier on a spectral mask margin. Power limit indications can be analyzed in scheduling mobile devices. Mobile devices with power limits can be scheduled on inner subbands. The power limits can be based at least in part on power amplifier headroom information. Other mobile devices can employ remaining portions of an allocated spectrum. Further, mobile devices can evaluate and establish a power amplifier backoff based upon the subband scheduling.

Abstract: Systems and methodologies are described that provide techniques for generating and utilizing reverse link feedback for interference management in a wireless communication system. Other Sector Interference (OSI) indicators are transmitted from an interfering access point to an access terminal. At the access terminal, an appropriate delta value(s) is combined with the received OSI indicators. The combined information is transmitted to the access point in a feedback so the serving sector access point can analyze the amount of interference. Based on the provided feedback from the terminal, the serving sector access point can assign resources for use by the terminal in communication with the serving sector.

Abstract: A system and method for the efficient transmission of information in a code division multiple access (CDMA) wireless telecommunication system. To increase the rate of reliable transmission, an orthogonal frequency-division multiplexing (OFDM) scheme is implemented in a direct-spread CDMA network, this combination sometimes being referred to as multi-carrier CDMA (MC-CDMA). Information (such as voice and data), interspersed with a known pilot signal, is encoded and spread across the frequency domain, rather than the time domain as in traditional CDMA; the allowable transmission bandwidth is divided into a number of carriers. To achieve even larger transmission rates, the guardband between carriers is eliminated. To prevent interference, the number of pilot transmissions is reduced and a corresponding number of frequency bins at the border of an OFDM block are loaded with zeros. The receiver simply ignores these subcarriers when reconstructing the transmitted signal.