Patent application number | Description | Published |
20080200204 | SYSTEMS AND METHODS FOR BACK-OFF AND CLIPPING CONTROL IN WIRELESS COMMUNICATION SYSTEMS - Systems and methods for controlling transmission power are provided. The systems and methods vary the power of a signal provided to a power amplifier based upon the location of a frequency or frequencies of signals to be transmitted within the transmission frequency band, the location of a hop region within the transmission frequency band, the bandwidth of signals to be transmitted, or combinations of these approaches. | 08-21-2008 |
20080214121 | POWER CONTROL FOR A WIRELESS COMMUNICATION SYSTEM UTILIZING ORTHOGONAL MULTIPLEXING - Techniques for adjusting transmit power to mitigate both intra-sector interference to a serving base station and inter-sector interference to neighbor base stations are described. The amount of inter-sector interference that a terminal may cause may be roughly estimated based on the total interference observed by each neighbor base station, channel gains for the serving and neighbor base stations, and the current transmit power level. The transmit power may be decreased if high interference is observed by a neighbor base station and increased otherwise. The transmit power may be adjusted by a larger amount and/or more frequently if the terminal is located closer to the neighbor base station observing high interference and/or if the current transmit power level is higher, and vice versa. The intra-sector interference is maintained within an acceptable level by limiting a received SNR for the terminal to be within a range of allowable SNRs. | 09-04-2008 |
20080219342 | CHANNEL EQUALIZATION WITH NON-COMMON MIDAMBLE ALLOCATION IN 3GPP TD-CDMA SYSTEMS - Systems and methodologies are described that facilitate implementing a linear adaptive equalizer receiver on the downlink link of a UMTS TDD wireless communication system. A reference signal can be generated based on multiple non-common midamble sequences in a time slot of a received transmission. Traffic-to-pilot ratios for channel codes in the time slot can be generated, and relative strengths of channel codes associated with specific midambles can be determined to weight the midamble. A plurality of the weighted midambles can then be utilized to generate a reference signal to train the equalizer, which can facilitate utilization of total aggregate midamble energy rather than midamble energy associated with a single midamble in the signal. | 09-11-2008 |
20080240159 | MAPPING OF SUBPACKETS TO RESOURCES IN A COMMUNICATION SYSTEM - Techniques for transmitting data in a communication system are described. A packet may be partitioned into multiple subpackets, and each subpacket may be encoded separately. The subpackets may be mapped to resources assigned for transmission of the packet, with at least one subpacket being mapped to a subset of the assigned resources. The assigned resources may include multiple tiles, with each tile corresponding to a block of time frequency resources. The subpackets may be mapped to the tiles such that (i) the subpackets are mapped to equal number of tiles to achieve similar decoding performance, (ii) each subpacket is mapped to at least N | 10-02-2008 |
20080253319 | RESTRICTIVE REUSE FOR A WIRELESS COMMUNICATION SYSTEM - For restrictive reuse, each cell (or each sector) is assigned (1) a set of usable subbands that may be allocated to users in the cell and (2) a set of forbidden subbands that is not used. The usable and forbidden sets for each cell are orthogonal to one other. The usable set for each cell also overlaps the forbidden set for each neighboring cell. A user u in a cell x may be allocated subbands in the usable set for that cell. If user u observes/causes high level of interference from/to a neighboring cell y, then user u may be allocated subbands from a “restricted” set containing subbands included in both the usable set for cell x and the forbidden set for cell y. User u would then observe/cause no interference from/to cell y. The subband restriction may be extended to avoid interference from multiple neighboring cells. | 10-16-2008 |
20080267086 | ESTIMATION OF THERMAL NOISE AND RISE-OVER-THERMAL IN A WIRELESS COMMUNICATION SYSTEM - Techniques for estimating thermal noise and rise-over-thermal (RoT) in a communication system are described. In an aspect, thermal noise in a sideband may be measured and used to estimate thermal noise in a signal band. In one design, received power in the sideband may be measured, e.g., by computing total power of FFT transform coefficients within the sideband. Thermal noise may be estimated based on (e.g., by filtering) the measured received power in the sideband. Received power in the signal band may also be measured. Total received power may be estimated based on (e.g., by filtering) the measured received power in the signal band. RoT may then be estimated based on the estimated thermal noise and the estimated total received power. The estimated RoT may be used to estimate an available load for a cell, which may be used to admit and/or schedule users in the cell. | 10-30-2008 |
20090022178 | METHODS AND SYSTEMS FOR ADAPTIVE TRANSMISSION OF CONTROL INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - A method for adaptive transmission of control information in a wireless communication system may include generating a control segment carrying control information. The control segment may have a configurable size. The method may also include generating a pointer for the control segment. The pointer may indicate a location of the control segment in a downlink subframe. The pointer may also indicate a size of the control segment. The method may also include sending the pointer and the control segment. | 01-22-2009 |
20090023466 | POWER CONTROL FOR A WIRELESS COMMUNICATION SYSTEM UTILIZING ORTHOGONAL MULTIPLEXING - Techniques for adjusting transmit power to mitigate both intra-sector interference to a serving base station and inter-sector interference to neighbor base stations are described. The amount of inter-sector interference that a terminal may cause may be roughly estimated based on the total interference observed by each neighbor base station, channel gains for the serving and neighbor base stations, and the current transmit power level. The transmit power may be decreased if high interference is observed by a neighbor base station and increased otherwise. The transmit power may be adjusted by a larger amount and/or more frequently if the terminal is located closer to the neighbor base station observing high interference and/or if the current transmit power level is higher, and vice versa. The intra-sector interference is maintained within an acceptable level by limiting a received SNR for the terminal to be within a range of allowable SNRs. | 01-22-2009 |
20090040975 | PEAK-TO-AVERAGE POWER RATIO MANAGEMENT FOR MULTI-CARRIER MODULATION IN WIRELESS COMMUNICATION SYSTEMS - Techniques for managing peak-to-average power ratio (PAPR) for multi-carrier modulation in wireless communication systems. Different terminals in a multiple-access system may have different required transmit powers. The number of carriers to allocate to each terminal is made dependent on its required transmit power. Terminals with higher required transmit powers may be allocated fewer carriers (associated with smaller PAPR) to allow the power amplifier to operate at higher power levels. Terminals with lower required transmit powers may be allocated more carriers (associated with higher PAPR) since the power amplifier is operated at lower power levels. The specific carriers to assign to the terminals may also be determined by their transmit power levels to reduce out-of-band emissions. Terminals with higher required transmit powers may be assigned with carriers near the middle of the operating band, and terminals with lower required transmit powers may be assigned with carriers near the band edges. | 02-12-2009 |
20090040981 | METHODS AND APPARATUS FOR IN-ORDER DELIVERY OF DATA PACKETS DURING HANDOFF - Methods, apparatus, systems and computer program products are defined that provide for in-order deliver of data packets during hand-off. The aspects provide for in-order delivery at Forward Link Serving eBS/Data Attachment Point (FLSE/DAP) switch and Reverse Link Serving eBS/Data Attachment Point (RLSE/DAP) switch. As such, present aspects provide for significant improvement in the throughput of applications, such as applications relying on Transmission Control Protocol (TCP), during handoff, in such networks as Ultra Mobile Broadband (UMB) and the like. | 02-12-2009 |
20090046713 | METHOD AND APPARATUS FOR TRANSMITTING NON-DECODABLE PACKETS - Acknowledgments (ACKs/NACKs) are suppressed when transmitting non-decodable packets in a communication system that utilizes HARQ. Non-decodable packets are transmitted to save system bandwidth and make the overall spectral efficiency higher. The transmitter and receiver know that in HARQ when the transmitter transmits a non-decodable packet to the receiver, this will cause the receiver to automatically transmit back a NACK. The transmitter and receiver exploit this fact by discarding and/or not transmitting the NACK (respectively). | 02-19-2009 |
20090052430 | METHOD AND APPARATUS FOR MITIGATING TEMPORARY LOSS OF SYNCHRONIZATION IN A WIRELESS COMMUNICATION SYSTEM - Techniques for mitigating temporary loss of synchronization in a wireless communication system are described. In an aspect, a cell may periodically broadcast a mode indicator to indicate synchronous operation or asynchronous operation by the cell. The cell may also broadcast its cell identity (ID), which may omit the mode indicator and would then remain unchanged when the cell switches between asynchronous and synchronous operation. In another aspect, the cell may send system time information indicative of its updated system time when switching from asynchronous operation to synchronous operation. The updated system time may be used for communication with terminals after the switch to synchronous operation. In yet another aspect, the cell may decrease its transmit power prior to switching synchronization mode, switch synchronization mode when its transmit power reaches a predetermined power level, and thereafter increase its transmit power. | 02-26-2009 |
20090074094 | BEACON SYMBOLS WITH MULTIPLE ACTIVE SUBCARRIERS FOR WIRELESS COMMUNICATION - Techniques for transmitting information using beacon symbols in a wireless communication system are described. In one design, a transmitter may map information to multiple subcarriers among a plurality of subcarriers, with the information being conveyed by the position of the multiple subcarriers. The transmitter may map the information to at least one non-binary symbol. The transmitter may then determine each of the multiple subcarriers based on one non-binary symbol or may determine all of the multiple subcarriers based on one non-binary symbol. The transmitter may generate a beacon symbol having the information mapped to the multiple subcarriers. The transmitter may use higher transmit power for the multiple subcarriers to allow receivers with low geometry to reliably receive the information. The use of multiple subcarriers may allow more information to be sent in the beacon symbol and may also improve frequency diversity. | 03-19-2009 |
20090075596 | ADAPTIVE DISTRIBUTED FREQUENCY PLANNING - Systems and methodologies are described that facilitate employing distributed frequency planning and reuse factor optimization based upon forward link and/or reverse link interference management techniques. An optimal reuse factor for a base station can be determined based upon a metric that evaluates levels of service associated with neighboring base stations. Moreover, a subset of available resource sets can be selected for use by the base station; thus, a base station specific collection of resource sets can be formed through such selection. Further, mappings of each resource set to a set of physical resources can be disseminated in a network or portion thereof. According to another example, frequency hopping can be constrained to use of resources within a resource set (rather than across more than one resource set) as provided in a base station specific hopping pattern. | 03-19-2009 |
20090075664 | MULTIPLEXED BEACON SYMBOLS FOR A WIRELESS COMMUNICATION SYSTEM - Techniques for transmitting information using beacon symbols are described. A transmitter may map first information to at least one subcarrier in a first set of subcarriers, with the first information being conveyed by the position of the at least one subcarrier. The transmitter may map second information to one or more subcarriers in a second set of subcarriers. The second information may be conveyed by one or more modulation symbols sent on the one or more subcarriers. The transmitter may generate at least one beacon symbol having the first information mapped to the at least one subcarrier in the first set and the second information mapped to the one or more subcarriers in the second set. In one design, the transmitter may frequency division multiplex the first information with the second information. In another design, the transmitter may puncture the second information on the at least one subcarrier with the first information. | 03-19-2009 |
20090082072 | SEMI-CONNECTED OPERATIONS FOR WIRELESS COMMUNICATIONS - Systems and methodologies are described that facilitate reducing battery consumption during periods of inactivity intermixed with traffic bursts in wireless communications systems. A semi-connected mode is provided that fast recognition of mobile devices upon wakeup and access while enabling mobile devices to operate in reduce power states. A mobile device operates in a semi-connected mode with all base stations in an active set of the mobile device. Moreover, mechanisms are provided to notify mobile devices of pending data while avoiding latency associated with paging channels. | 03-26-2009 |
20090109939 | PILOT REPORT BASED ON INTERFERENCE INDICATIONS IN WIRELESS COMMUNICATION SYSTEMS - Systems and methodologies are described that facilitate employing interference-overload indications to generate pilot strength reports that can be leveraged to mitigate reverse link interference. An affected base station can send interference-overload indications when experiencing a strong interference/jamming scenario due to reverse link transmission by an offending access terminal. The offending access terminal can monitor interference-overload indications from the affected base station (e.g., although the affected base station can be excluded from an active set of the offending access terminal) and send a pilot strength report to a serving base station in response. The serving base station can receive the interference induced pilot strength report and command the offending access terminal not to transmit on certain channel resources (e.g., time, frequency, spatial, . . . ); thus, the affected base station can use these resources to schedule transmission(s) by access terminal(s) served thereby. | 04-30-2009 |
20090122782 | SYNCHRONIZATION OF WIRELESS NODES - A first wireless node may synchronize its timeslots with the timeslots of a second wireless node that was previously transmitting and receiving data in an asynchronous manner with respect to the timeslots of the first wireless node. By synchronizing timeslots, the wireless nodes may avoid interference that may otherwise occur if the wireless nodes operate in an asynchronous manner. A wireless node shares its timing information with other wireless nodes by repeatedly transmitting timing reference signals in conjunction with a synchronization metric that defines the relative priority of the timing reference. In the event a wireless node does not receive a GPS-based timing reference, the wireless node may synchronize to a timing reference based on the parameters of the synchronization metric of that timing reference. In the event a wireless node does not receive any timing references, the wireless node may define and advertise it's a timing reference and associated synchronization metric. To avoid synchronization race conditions, the synchronization metrics may be defined such that wireless nodes that have different timing references will advertise different synchronization metrics. | 05-14-2009 |
20090129333 | PREAMBLE DESIGN FOR A WIRELESS SIGNAL - Providing for management of wireless communications in a heterogeneous wireless access point (AP) environment is described herein. By way of example, system data of an over-the-air message can be configured to include information identifying a distinct type of transmitting base station. In some aspects, the information can include an access type of the base station and/or a sector ID for distinguishing the base station among large numbers of other base stations. According to other aspects, system data transmitted on the wireless signal can include wireless channel resources designated for a particular type of base station, or blanked by the transmitting base station, to facilitate interference reduction on such resources. By employing aspects of wireless communication management disclosed herein, efficient and reliable communication can be affected in large heterogeneous AP networks. | 05-21-2009 |
20090129350 | PREAMBLE DESIGN FOR A WIRELESS SIGNAL - Providing for management of wireless communications in a heterogeneous wireless access point (AP) environment is described herein. By way of example, system data of an over-the-air message can be configured to include information identifying a distinct type of transmitting base station. In some aspects, the information can include an access type of the base station and/or a sector ID for distinguishing the base station among large numbers of other base stations. According to other aspects, the information can include wireless channel resources designated for a particular type of base station, or blanked by the transmitting base station, to facilitate interference reduction on such resources. By employing aspects of wireless communication management disclosed herein, efficient and reliable communication can be affected in large heterogeneous AP networks. | 05-21-2009 |
20090129354 | ACCESS POINT CONFIGURATION SCHEMES - An access point is configured based on acquired information. An access point may be configured based on the configuration(s) of at least one other access point. An identifier to be transmitted by an access point may be selected based on the identifier(s) transmitted by at least one other access point. An access point may configure itself with assistance from a configuration server. For example, the access point may send information such as the location of the access point to a configuration server and the configuration server may respond with a list of neighboring access points for that access point. A configuration server may provide configuration information to an access point based on the location of the access point. A configuration server also may direct an access point to a different configuration server. | 05-21-2009 |
20090131061 | BEACON-BASED CONTROL CHANNELS - Systems and methodologies are described that facilitate transmitting control information in wireless networks. Portions of bandwidth can be blanked for transmitting control information, and the control information transmitters can utilize beacon symbols to convey the control information. In this regard, interference is mitigated with respect to data transmissions over the control information bandwidth. Selected frequencies of the beacon symbols in a codeword can be used to indicate the control information. The codewords can be encoded with an error control code to provide redundancy for decoding in the presence of some interference. | 05-21-2009 |
20090131098 | PREAMBLE DESIGN FOR A WIRELESS SIGNAL - Providing for management of wireless communications in a heterogeneous wireless access point (AP) environment is described herein. By way of example, system data of an over-the-air message can be configured to include information identifying a distinct type of transmitting base station. In some aspects, the information can include an access type of the base station and/or a sector ID for distinguishing the base station among large numbers of other base stations. According to other aspects, the information can include wireless channel resources designated for a particular type of base station, or blanked by the transmitting base station, to facilitate interference reduction on such resources. By employing aspects of wireless communication management disclosed herein, efficient and reliable communication can be affected in large heterogeneous AP networks. | 05-21-2009 |
20090149140 | POWER CONTROL UTILIZING MULTIPLE RATE INTERFERENCE INDICATIONS - 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. | 06-11-2009 |
20090190500 | SERVING CELL SELECTION IN WIRELESS COMMUNICATIONS - Systems and methodologies are described that facilitate selecting and/or reselecting one or more access points, related cells, or carriers based at least in part on calculating an energy efficiency related to the access points. In particular, the energy efficiency can be based at least in part on an estimated pathloss and/or a level of interference related to communicating with the access points. Moreover, load parameters related to the access point can be received and evaluated in selecting and/or reselecting the access point. Thus, access points can be selected or reselected based on parameters other than forward link transmit power. In addition, pathloss and/or interference levels can be weighed based on access point type to prevent macrocell overloading. | 07-30-2009 |
20090191876 | WIRELESS HANDOFFS BETWEEN MULTIPLE NETWORKS - The disclosure is directed to a mobile communication device, and method for handing off a mobile communications device between two networks. A processor in the mobile device may be used to establish a network connection with a server in a first network while supporting a call in a second network. The mobile device may also include a transceiver that receives information from the server relating to the network connection. The processor may use the information, local measurements, or both to determine whether to handoff the call to the first network. | 07-30-2009 |
20090191910 | POWER HEADROOM MANAGEMENT IN WIRELESS COMMUNICATION SYSTEMS - Systems and methodologies are described that facilitate power headroom management in a wireless communication system. As described herein, a predefined relationship between locations along a system frequency band and corresponding power backoff parameters is utilized to minimize spurious emissions outside the system frequency band and/or excessive interference by, for example, associating locations near one or more edges of the permitted frequency band with substantially high power backoff parameters. As further described herein, the predefined relationship can be known a priori to the base station and the mobile terminal such that the power backoff | 07-30-2009 |
20090196221 | METHOD AND APPARATUS FOR PROVIDING SIGNALING ACCESS - Signaling-only access may be established with an access node under certain circumstances such as, for example, upon determining that a node is not authorized for data access at the access node. A node that is not authorized for data access at an access node may still be paged by the access node through the use of signaling-only access. In this way, transmissions by the access node may not interfere with the reception of pages at the node. A first node may be selected for providing paging while a second node is selected for access under certain circumstances such as, for example, upon determining that the second node provides more desirable service than the first node. | 08-06-2009 |
20090197538 | INTERFERENCE REDUCTION REQUEST IN A WIRELESS COMMUNICATION SYSTEM - 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. | 08-06-2009 |
20090197570 | PAGING AND ACCESS VIA DIFFERENT NODES - Signaling-only access may be established with an access node under certain circumstances such as, for example, upon determining that a node is not authorized for data access at the access node. A node that is not authorized for data access at an access node may still be paged by the access node through the use of signaling-only access. In this way, transmissions by the access node may not interfere with the reception of pages at the node. A first node may be selected for providing paging while a second node is selected for access under certain circumstances such as, for example, upon determining that the second node provides more desirable service than the first node. | 08-06-2009 |
20090197588 | BACKHAUL SIGNALING FOR INTERFERENCE AVOIDANCE - Providing for interference reduction and/or avoidance utilizing backhaul signaling between wireless access points (APs) of a wireless access network (AN) is described herein. By way of example, an interference avoidance request (IAR) can be issued by an AP to reduce signal interference on forward link (FL) and/or downlink (DL) transmissions by neighboring APs. The IAR can be routed via a backhaul network and/or over-the-air via access terminals (ATs) coupled with the AP or one or more interfering APs. Upon receiving the IAR, an interfering AP can determine reduced transmit power levels for FL and/or RL transmissions and respond to the IAR. The response can include reduced power levels and can be sent via the backhaul network or OTA. By employing the backhaul network in full or in part, interference avoidance can be conducted even for semi-planned or unplanned heterogeneous networks coupled by the backhaul. | 08-06-2009 |
20090197590 | SHORT-TERM INTERFERENCE MITIGATION IN A WIRELESS COMMUNICATION SYSTEM - 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. | 08-06-2009 |
20090197603 | SERVING BASE STATION SELECTION IN A WIRELESS COMMUNICATION NETWORK - 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. | 08-06-2009 |
20090197629 | POWER DECISION PILOT FOR A WIRELESS COMMUNICATION SYSTEM - 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. | 08-06-2009 |
20090197631 | INTERFERENCE MITIGATION FOR CONTROL CHANNELS IN A WIRELESS COMMUNICATION NETWORK - Techniques for mitigating interference on control channels in a wireless communication network are described. In an aspect, high interference on radio resources used for a control channel may be mitigated by sending a request to reduce interference to one or more interfering stations. Each interfering station may reduce its transmit power on the radio resources, which may then allow the control channel to observe less interference. In one design, a user equipment (UE) may detect high interference on radio resources used for a control channel by a desired base station. The UE may send a request to reduce interference on the radio resources to an interfering base station, which may reduce its transmit power on the radio resources. The UE may receive the control channel on the radio resources from the desired base station and may observe less interference from the interfering base station. | 08-06-2009 |
20090201846 | SYSTEM AND METHOD FOR SCHEDULING OVER MULTIPLE HOPS - 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. Conversely, when the allocation of resources is explicit the relay station does transmit control information. | 08-13-2009 |
20090247172 | LOW REUSE PREAMBLE FOR A WIRELESS COMMUNICATION NETWORK - Techniques for sending low reuse preambles in a wireless network are described. In an aspect, a base station may send a low reuse preamble on reserved frequency resources to allow terminals to detect the base station even in the presence of strong interfering base stations. The base station may generate the low reuse preamble to include a pilot portion and a data portion. The base station may determine frequency resources reserved for sending low reuse preambles by base stations. The base station may then send the low reuse preamble on the reserved frequency resources, e.g., at a pseudo-randomly selected time. A terminal may detect for low reuse preambles sent by the base stations on the reserved frequency resources. The terminal may recover information for a base station from a detected low reuse preamble. | 10-01-2009 |
20090247181 | LONG-TERM INTERFERENCE MITIGATION IN AN ASYNCHRONOUS WIRELESS NETWORK - Techniques for mitigating interference in a wireless communication network are described. A terminal may desire to communicate with a weaker serving base station and may observe high interference from a strong interfering base station. The two base stations may be asynchronous and have different frame timing. In an aspect, high interference may be mitigated by having the interfering base station reserve downlink and/or uplink resources. The interfering base station may transmit at a low power level or not at all on the reserved downlink resources to reduce interference to the terminal. Terminals served by the interfering base station may transmit at a low power level or not at all on the reserved uplink resources to reduce interference at the serving base station. The terminal may then be able to communicate with the serving base station. | 10-01-2009 |
20090257388 | SYSTEMS AND METHODS TO DEFINE CONTROL CHANNELS USING RESERVED RESOURCE BLOCKS - Systems and methodologies are described that facilitate defining new control channels in legacy wireless networks. Control data resources for new systems can be defined over resources reserved for general data communications in the legacy wireless network specification. In this regard, legacy devices can still be supported by devices implementing new control data resources, and the new control data resources can avoid substantial interference that is typically exhibited over legacy control and/or reference signal resources by instead using the general data resources. In addition, new system devices can avoid scheduling data communication resources over the new control resources to create a substantially non-interfered global control segment. Control data can be transmitted over the segment using beacon-based technologies, reuse schemes, and/or the like. | 10-15-2009 |
20090274232 | REVERSE LINK POWER CONTROL IN AN ORTHOGONAL SYSTEM - A closed-loop reverse-link power control algorithm for a frequency hopping orthogonal frequency division multiple access (FH-OFDMA) system is described. The power control algorithm adjusts the user's transmit power based on effective carrier-to-interference (C/I) and Received-Power-Over-Thermal (RpOT) measurements. The algorithm is inherently stable and is effective for FH-OFDMA systems with retransmissions. | 11-05-2009 |
20090286563 | METHOD AND APPARATUS FOR USING VIRTUAL NOISE FIGURE IN A WIRELESS COMMUNICATION NETWORK - Techniques for using virtual noise figure for various functions in a wireless communication network are described. A virtual noise figure is an indication of a virtual noise level at a receiver, which may be higher than an actual noise level at the receiver. In an aspect, virtual noise figure may be used for serving base station selection. A terminal may receive information indicative of a virtual noise figure for each of at least one base station. The terminal may select a serving base station based on the virtual noise figure for each base station. The terminal may send data to the serving base station at a rate selected based on an actual noise figure for the serving base station. In other aspects, virtual noise figure may be used for interference management and/or power control. | 11-19-2009 |
20090304120 | WIRELESS COMMUNICATION SYSTEM WITH IMPROVED BROADCAST COVERAGE - Techniques to transmit data with cyclic delay diversity and pilot staggering are described. For cyclic delay diversity, OFDM symbols having different cyclic delay durations are generated. The cyclic delay durations for the OFDM symbols may be selected to be time varying with respect to the cyclic delay durations for OFDM symbols transmitted by a neighboring base station. An FDM pilot is generated and multiplexed on multiple sets of subbands in different symbol periods. Waveforms for a second radio technology (e.g., W-CDMA) may be generated for data to be transmitted with this radio technology. The OFDM symbols are multiplexed onto time slots used for OFDM, and the waveforms for the second radio technology are multiplexed onto time slots used for this radio technology. One or multiple modulated signals may be generated based on the multiplexed OFDM symbols and waveforms. Each modulated signal is transmitted from a respective antenna. | 12-10-2009 |
20090323577 | BROADCAST-MULTICAST TRANSMISSION WITH RATE ADAPTION - 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. | 12-31-2009 |
20100008230 | ACCESS MECHANISMS FOR BASE STATIONS IN HETEROGENEOUS ACCESS POINT NETWORKS - 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. | 01-14-2010 |
20100008258 | ACCESS POINT IDENTIFIER CONFIGURATION PROCEDURE - In an access point identifier configuration scheme, different procedures are used for configuring (e.g., updating) different types of access points. For example, the criteria used to determine which identifiers are to be assigned to mobile access points may be different than the criteria used to determine which identifiers are to be assigned to stationary access points. | 01-14-2010 |
20100020771 | METHOD AND APPARATUS FOR MITIGATING PILOT POLLUTION IN A WIRELESS NETWORK - Techniques for mitigating pilot pollution in a wireless network are described. In an aspect, pilot pollution may be mitigated by reducing density and/or transmit power of common pilots whenever possible. A cell may send a common pilot at a first density and a first transmit power level during a first time period and may send the common pilot at a second density and a second transmit power level during a second time period. The second density may be lower than the first density and/or the second transmit power level may be lower than the first transmit power level. Lower density may be achieved by sending the common pilot less frequently, on fewer subcarriers, and/or from fewer antennas. The cell may determine whether to reduce the density and/or transmit power of the common pilot based on network loading, SINRs of terminals, etc. In another aspect, pilot pollution may be mitigated by performing pilot cancellation at a terminal. | 01-28-2010 |
20100029265 | SYSTEMS AND METHODS THAT UTILIZE A CAPACITY-BASED SIGNAL-TO-NOISE RATIO TO PREDICT AND IMPROVE MOBILE COMMUNICATION - Techniques for utilizing a capacity-based effective signal-to-noise ratio (SNR) to improve wireless communication are described herein. In an embodiment, a mobile terminal can determine the effective SNR from a forward link channel using pilot/data symbols. The mobile terminal can convey the effective SNR to a base station. In order to minimize transmission overhead, the mobile terminal can quantize the effective SNR prior to transmitting it to the base station. In another embodiment, the base station can determine the effective SNR from a reverse link. The base station can utilize the effective SNR to facilitate scheduling transmissions from the mobile terminal, transmitting power control commands to the mobile terminal, and determining a supporting data rate for the mobile terminal, for example. Suitable SNRs include constrained, unconstrained, average, and/or approximated effective SNRs. In addition, various filters, such as an averaging filter, can be utilized to further process the effective SNR. | 02-04-2010 |
20100039948 | INTERFERENCE MANAGEMENT BASED ON ENHANCED PILOT MEASUREMENT REPORTS - Techniques for managing interference in a wireless network are described. A base station may receive enhanced pilot measurement reports from user equipments (UEs) and may make an interference management decision based on the received reports. The base station may select a serving base station for a UE based on an enhanced pilot measurement report received from the UE. The base station may determine resources with a low target interference level at a neighbor base station and may avoid scheduling a UE for uplink transmission on the resources. The base station may also determine whether to reserve resources for a neighbor base station based on data performance of the neighbor base station, whether the neighbor base station observes high interference from UEs served by the base station, or whether UEs served by the neighbor base station observe high interference from the base station, which may be determined based on the enhanced pilot measurement reports. | 02-18-2010 |
20100046447 | BEACON SYMBOL ORTHOGONALIZATION - Beacon symbols are sent periodically from the base stations in an OFDM system. The entire power of the base station, or a large portion of it is concentrated in these symbols, thus they are very easily recognized by the mobile stations. The frequencies upon which these symbols are transmitted and the time at which they are transmitted communicates information such as the base station/sector identity and the preferred carrier of the given base station/sector to the mobile station. In order to avoid collision between the beacon symbols of different base stations and sectors, the beacon symbols from different base stations/sectors are transmitted at different symbols times and on different subcarriers. | 02-25-2010 |
20100061341 | INTRA-CELL COMMON REUSE FOR A WIRELESS COMMUNICATION SYSTEM - To avoid or reduce intra-cell interference, each sector of a cell is associated with a sector-specific set of system resources (e.g., subbands) and at least one non-overlapping common set of system resources. Each common set for each sector includes system resources observing little or no interference from at least one other sector in the cell. The channel condition for a terminal in a given sector x is ascertained based on forward and/or reverse link measurements for the terminal. The terminal is assigned system resources from a common set or a sector-specific set for sector x based on the terminal's channel condition. For example, if the terminal observes high interference from another sector y, then the terminal is assigned system resources from a common set that observes little or no interference from sector y. The techniques may be used for an OFDMA system that uses frequency hopping. | 03-11-2010 |
20100067469 | INTERFERENCE MANAGEMENT FOR DIFFERENT WIRELESS COMMUNICATION TECHNOLOGIES - Systems and methodologies are described that facilitate avoiding interference with disparate communication technologies when allocating and/or utilizing wireless communication resources. Access points can generate resource assignments for mobile devices based at least in part on resources utilized by the disparate communication technology devices, such as to avoid such resources, allocate narrow bands over such resources, avoid or limit allocations in a measurement gap during which disparate communication technology devices communicate, and/or the like to mitigate interference over the resources. Mobile devices can provide such information to the access point, such as a communication technology to avoid interfering, resources utilized by devices of the communication technology, etc. This information can be acquired by receiving signals from the devices, detecting presence of the devices, and/or the like. In addition, mobile device can reduce transmission power over resources used by the disparate communication technology. | 03-18-2010 |
20100067474 | PEAK-TO-AVERAGE POWER RATIO MANAGEMENT FOR MULTI-CARRIER MODULATION IN WIRELESS COMMUNICATION SYSTEMS - Techniques for managing peak-to-average power ratio (PAPR) for multi-carrier modulation in wireless communication systems. Different terminals in a multiple-access system may have different required transmit powers. The number of carriers to allocate to each terminal is made dependent on its required transmit power. Terminals with higher required transmit powers may be allocated fewer carriers (associated with smaller PAPR) to allow the power amplifier to operate at higher power levels. Terminals with lower required transmit powers may be allocated more carriers (associated with higher PAPR) since the power amplifier is operated at lower power levels. The specific carriers to assign to the terminals may also be determined by their transmit power levels to reduce out-of-band emissions. Terminals with higher required transmit powers may be assigned with carriers near the middle of the operating band, and terminals with lower required transmit powers may be assigned with carriers near the band edges. | 03-18-2010 |
20100067598 | Method and System for LLR Buffer Reduction in a Wireless Communication Modem - A system involves a transmitting device (for example, a first wireless communication device) and a receiving device (for example, a second wireless communication device). In the receiving device, LLR (Log-Likelihood Ratio) values are stored into an LLR buffer. LLR bit width is adjusted as a function of packet size of an incoming transmission to reduce the LLR buffer size required and/or to prevent LLR buffer capacity from being exceeded. The receiver may use a higher performance demodulator in order to maintain performance despite smaller LLR bit width. In the transmitting device, encoder code rate is adjusted as a function of receiver LLR buffer capacity and packet size of the outgoing transmission such that receiver LLR buffer capacity is not exceeded. Any combination of receiver LLR bit width adjustment, demodulator selection, and encoder code rate adjustment can be practiced to reduce LLR buffer size required while maintaining performance. | 03-18-2010 |
20100080163 | APPARATUS AND METHODS OF PROVIDING AND RECEIVING VENUE LEVEL TRANSMISSIONS AND SERVICES - A venue-cast system and method for providing and receiving venue level transmissions and services, including discovery of a venue specific transmission by receiving an overhead signal from a non-venue network, extracting information for receiving the venue specific transmission from the overhead signal, and tuning to receive the venue specific transmission based on the extracted information. The venue level transmission may be provided and received in a manner that does not prevent an access terminal from receiving a local area or wide area transmission. | 04-01-2010 |
20100097976 | INCREMENTAL REDUNDANCY RELAYS FOR WIRELESS COMMUNICATION - Techniques for relaying transmissions in a wireless communication network are described. In one design, a relay may receive at least one assignment for a packet, which may be sent to the relay or intercepted by the relay. The relay may receive at least one transmission of a packet sent from a transmitter to a receiver. The relay may process the at least one transmission to decode the packet and may generate at least one additional transmission of the packet after correctly decoding the packet. The relay may send the at least one additional transmission of the packet to the receiver. The transmission(s) and the additional transmission(s) may be HARQ transmissions with different redundancy information for the packet. The transmitter may send transmissions until an acknowledgement (ACK) is received from the receiver or the relay. The relay may send additional transmissions until an ACK is received from the receiver. | 04-22-2010 |
20100099428 | NULL PILOTS FOR INTERFERENCE ESTIMATION IN A WIRELESS COMMUNICATION NETWORK - 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. | 04-22-2010 |
20100099449 | INTERFERENCE MANAGEMENT WITH REDUCE INTERFERENCE REQUESTS AND INTERFERENCE INDICATORS - 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. | 04-22-2010 |
20100103858 | METHOD AND APPARATUS FOR COMMUNICATING IN A RELAY COMMUNICATION NETWORK - Techniques for transmitting data in a relay communication network are described. In an aspect, stations in the relay network may be grouped into multiple depths, and stations at each depth may send the same transmission in each time interval. Packets may be transmitted in a pipelined manner in the relay network. Transmissions of a packet may be sent by stations at progressively higher depth in successive time intervals. A station may perform auto-configuration, attempt to decode transmissions from stations at different depths, and determine its depth based on decoding results. In another aspect, stations at each depth may transmit the same synchronization signal, and stations at different depths may transmit different synchronization signals. In one design, the synchronization signals for different depths may be different pilots, which may be generated with different scrambling codes or different orthogonal codes or may be multiplexed in frequency and/or time. | 04-29-2010 |
20100105317 | DATA RECEPTION WITH INTERFERENCE CANCELLATION IN A RELAY COMMUNICATION NETWORK - Techniques for transmitting and receiving data in a relay communication network are described. Stations in the relay network may be grouped into multiple depths. Packets may be transmitted in a pipelined manner, with stations at progressively higher depth sending transmissions of a packet in successive frames. In an aspect, a station may receive data with interference cancellation. The station may obtain a received signal containing transmissions of a first packet from stations at a first depth and transmissions of a second packet from stations at a second depth. The first and second stations may be downstream and upstream stations, respectively, or may be upstream stations at different depths. The station may estimate and cancel interference due to the transmissions of the first packet from the received signal to obtain an interference canceled signal. The station may then process the interference canceled signal for the second packet. | 04-29-2010 |
20100110966 | INCREMENTAL REDUNDANCY RELAYS FOR BROADCAST TRANSMISSION - Techniques for relaying a broadcast transmission in a wireless network are described. In one design, a relay may receive at least one transmission of a packet from a transmitter (e.g., a broadcast station) and may process the at least one transmission to decode the packet. The relay may generate at least one remaining transmission of the packet after correctly decoding the packet. The transmitter may broadcast multiple transmissions of the packet to receivers. The at least one transmission may be at least one of the multiple transmissions, and the at least one remaining transmission may be remaining ones of the multiple transmissions. The relay may send the at least one remaining transmission of the packet at the same time and on the same resources used by the transmitter. The multiple transmissions may be HARQ transmissions containing different redundancy information for the packet. | 05-06-2010 |
20100119005 | RATE ADAPTIVE TRANSMISSION SCHEME FOR MIMO SYSTEMS - A rate adaptive transmission scheme for MIMO systems, which can transmit a variable number of data symbol streams, provide transmit diversity for each data symbol stream, and fully utilize the total transmit power of the system and the full power of each antenna. In one method, at least one data symbol stream is received for transmission from a plurality of antennas. Each data symbol stream is scaled with a respective weight corresponding to the amount of transmit power allocated to that stream. The scaled data symbol stream(s) are multiplied with a transmit basis matrix to provide a plurality of transmit symbol streams for the plurality of antennas. The transmit basis matrix (e.g., a Walsh-Hadamard matrix or a DFT matrix) is defined such that each data symbol stream is transmitted from all antennas and each transmit symbol stream is transmitted at (or near) the full power for the associated antenna. | 05-13-2010 |
20100159940 | METHODS AND APPARATUS FOR FLEXIBLE SPECTRUM ALLOCATION IN COMMUNICATION SYSTEMS - The disclosed embodiments provide for methods and systems for flexibly allocating a shared frequency spectrum to a plurality of users, the spectrum may have a first number of segments, each segment having a second number of clusters associated with a certain sector/cell. In one aspect, a method for flexibly allocating a shared frequency spectrum to a plurality of users comprises the acts of fixedly assigning a first group of clusters to a first group of users, such that the first group of users stay fixed to the assigned clusters, and assigning a second group of clusters to a second group of users, such that the second group of users hop within the assigned clusters. | 06-24-2010 |
20100165882 | CENTRALIZED CONTROL OF PEER DISCOVERY PILOT TRANSMISSION - Techniques for centralized control of peer discovery pilot transmission are described. In an aspect, a designated network entity (e.g., a base station or a network controller) may control transmission of peer discovery pilots by stations located within its coverage area. In one design, the network entity may receive signaling triggering peer discovery pilot transmission. The network entity may direct each of at least one station to transmit a peer discovery pilot to allow one or more stations to detect the at least one station. The peer discovery pilot may include at least one synchronization signal or at least one reference signal. The network entity may receive pilot measurements from the one or more stations for peer discovery pilots from peer stations and/or reference signals from base stations. The network entity may determine whether or not to select peer-to-peer communication for two stations based on the pilot measurements. | 07-01-2010 |
20100167743 | CENTRALIZED CONTROL OF RELAY OPERATION - Techniques for centralized control of relay operation are described. In an aspect, a designated network entity (e.g., a base station or a network controller) may control the operation of relay stations within its coverage area. The network entity may select certain user equipments (UEs) to be relay UEs that can serve as relay stations for other UEs, e.g., based on pathloss between the UEs and a base station, the locations of the UEs, battery power levels of the UEs, fairness considerations, etc. The network entity may also select a specific relay UE to serve as a relay station for a client UE desiring to communicate with a base station, e.g., based on pilot measurements from relay UEs for the client UE. The network entity may also control transmission of discovery pilots by relay UEs and/or client UEs for relay detection. | 07-01-2010 |
20100169498 | CENTRALIZED CONTROL OF PEER-TO-PEER COMMUNICATION - Techniques for centralized control of peer-to-peer (P2P) communication and centralized control of femto cell operation are described. For centralized control of P2P communication, a designated network entity (e.g., a base station) may control P2P communication of stations (e.g., UEs) located within its coverage area. The designated network entity may receive an indication of a first station (e.g., a UE) desiring to communicate with a second station (e.g., another UE). The designated network entity may determine whether or not to select peer-to-peer communication for the first and second stations, e.g., based on the quality of their communication link. The designated network entity may assign resources to the stations if peer-to-peer communication is selected. For centralized control of femto cell operation, the designated network entity may control the operation of femto cells (e.g., may activate or deactivate femto cells) within its coverage area. | 07-01-2010 |
20100172311 | HEARABILITY IMPROVEMENTS FOR REFERENCE SIGNALS - Systems and methodologies are described that facilitate providing high reuse for transmitting reference signals, such as positioning reference signals (PRS) and cell-specific reference signals (CRS), to improve hearability thereof for applications such as trilateration and/or the like. In particular, PRSs can be transmitted in designated or selected positioning subframes. Resource elements within the positioning subframe can be selected for transmitting the PRSs and can avoid conflict with designated control regions, resource elements used for transmitting cell-specific reference signals, and/or the like. Resource elements for transmitting PRSs can be selected according to a planned or pseudo-random reuse scheme. In addition, a transmit diversity scheme can be applied to the PRSs to minimize impact of introducing the PRSs to legacy devices. Moreover, portions of a subframe not designated for PRS transmission can be utilized for user plane data transmission. | 07-08-2010 |
20100190447 | DOWNLINK INTERFERENCE CANCELLATION METHODS - A method to mitigate interference in a wireless system is provided. The method includes processing a set of radio network identifiers and limiting a number of hypotheses associated with the radio network identifiers in order to mitigate interference in a wireless network. In another aspect, the method includes processing a set of hypotheses and limiting the set of hypotheses by limiting a number of downlink grants to a common space, limiting the number of downlink grants to a number of instances, or limiting the number of grants to a physical downlink control channel (PDCCH) type. In yet another aspect, the method includes processing a downlink set and generating a target termination level for the downlink data set, the termination level associated with a Hybrid automatic repeat-request. | 07-29-2010 |
20100195630 | QUASI-ORTHOGONAL MULTIPLEXING FOR A MULTI-CARRIER COMMUNICATION SYSTEM - For quasi-orthogonal multiplexing in an OFDMA system, multiple (M) sets of traffic channels are defined for each base station. The traffic channels in each set are orthogonal to one another and may be pseudo-random with respect to the traffic channels in each of the other sets. The minimum number of sets of traffic channels (L) is used to support a given number of (U) terminals selected for data transmission, where M≧L≧1 and U≧1. Each terminal transmits data and pilot symbols on its traffic channel. A base station receives data transmissions from all terminals and may perform receiver spatial processing on received symbols with spatial filter matrices to obtain detected data symbols. The spatial filter matrix for each subband may be derived based on channel response estimates for all terminals transmitting on that subband. | 08-05-2010 |
20100195747 | METHOD AND APPARATUS FOR PERFORMING JOINT DETECTION WITH A COMMON MIDAMBLE - Techniques for performing joint detection with a common midamble for downlink transmission are described. In one design, a user equipment (UE) may obtain samples for a burst transmitted by a Node B on the downlink. The burst may include at least one data field and a common midamble. The UE may derive a channel impulse response estimate for each of multiple orthogonal codes based on (i) a channel impulse response estimate derived based on samples for the common midamble and (ii) a traffic-to-pilot ratio (T2P) estimated for that orthogonal code based on the samples for burst. The UE may perform joint detection, for the multiple orthogonal codes, on samples for the at least one data field based on the multiple channel impulse response estimates. | 08-05-2010 |
20100215030 | QUICK PAGING CHANNEL WITH REDUCED PROBABILITY OF MISSED PAGE - A quick paging channel in a random access wireless communication system includes at least one bit in a quick paging frame identifying the presence of a paging message for an access terminal or group of access terminals. The quick paging bits identifying the presence of a paging message for a first access terminal is encoded with one or more quick paging bits corresponding to one or more additional access terminals to produce one or more forward error correction bits. The jointly encoded quick paging bits are broadcast to the access terminals by time division multiplexing the quick paging frame with additional frames of information. | 08-26-2010 |
20100220708 | HIERARCHICAL CODING WITH MULTIPLE ANTENNAS IN A WIRELESS COMMUNICATION SYSTEM - Techniques are provided for performing hierarchical coding in a multi-antenna communication system (e.g., a SIMO, MISO, or MIMO system). At a transmitter, a base stream and an enhancement stream are coded and modulated separately to obtain first and second data symbol streams, respectively. The first data symbol stream is processed in accordance with a first spatial processing scheme (e.g., a transmit diversity or a spatial multiplexing scheme) to obtain a first set of symbol substreams. The second data symbol stream is processed in accordance with a second spatial processing scheme (e.g., transmit diversity or spatial multiplexing) to obtain a second set of symbol substreams. The first set of symbol substreams is combined (e.g., using time division multiplexing or superposition) with the second set of symbol substreams to obtain multiple transmit symbol streams for transmission from multiple transmit antennas. A receiver performs complementary processing to recover the base stream and enhancement stream. | 09-02-2010 |
20100238896 | ON-HAND REVERSE-LINK PILOT TRANSMISSION - Pilots are transmitted on demand on a reverse link and used for channel estimation and data transmission on a forward link. A base station selects at least one terminal for on-demand pilot transmission on the reverse link. Each selected terminal is a candidate for receiving data transmission on the forward link. The base station assigns each selected terminal with a time-frequency allocation, which may be for a wideband pilot, a narrowband pilot, or some other type of pilot. The base station receives and processes on-demand pilot transmission from each selected terminal and derives a channel estimate for the terminal based on the received pilot transmission. The base station may schedule terminals for data transmission on the forward link based on the channel estimates for all selected terminals. The base station may also process data (e.g., perform beamforming or eigensteering) for transmission to each scheduled terminal based on its channel estimate. | 09-23-2010 |
20100278058 | METHOD AND APPARATUS FOR FACILITATING MULTICARRIER DIFFERENTIAL CHANNEL QUALITY INDICATOR (CQI) FEEDBACK - Methods, apparatuses, and computer program products are disclosed for facilitating multicarrier channel quality indicator (CQI) feedback. A wireless terminal communicates with a base station via a plurality of carriers and receives configuration data generated by the base station identifying a subset of carriers included in the plurality of carriers. The wireless terminal identifies a reference carrier and reports a reference CQI value corresponding to the reference carrier to the base station. The wireless terminal also reports a differential CQI value derived from the reference CQI value to the base station. | 11-04-2010 |
20100279707 | TIME OF ARRIVAL (TOA) ESTIMATION FOR POSITIONING IN A WIRELESS COMMUNICATION NETWORK - Techniques for determining time of arrivals (TOAs) of signals in a wireless communication network are described. Each cell may transmit (i) synchronization signals on a set of contiguous subcarriers in the center portion of the system bandwidth and (ii) reference signals on different sets of non-contiguous subcarriers distributed across the system bandwidth. A UE may determine TOA for a cell based on multiple signals transmitted on different sets of subcarriers. The UE may perform correlation for a first signal (e.g., a synchronization signal) from the cell to obtain first correlation results for different time offsets. The UE may perform correlation for a second signal (e.g., a reference signal) from the cell to obtain second correlation results for different time offsets. The UE may combine the first and second correlation results and may determine the TOA for the cell based on the combined correlation results. | 11-04-2010 |
20100291963 | TRANSMISSION POWER MANAGEMENT FOR A MOBLIE DEVICE SUPPORTING SIMULTANEOUS TRANSMISSION ON MULTIPLE AIR INTERFACES - Systems and methods for transmission power management for a mobile device supporting simultaneous transmission on multiple air interfaces are disclosed. In one embodiment, the method comprises determining a transmission power level for each air interface, comparing the transmission power levels to a threshold power level, and adjusting at least one of the transmission power levels based on said comparison. | 11-18-2010 |
20100303165 | PILOT TRANSMISSION AND CHANNEL ESTIMATION FOR AN OFDM SYSTEM WITH EXCESS DELAY SPREAD - Pilot transmission and channel estimation techniques for an OFDM system with excess delay spread are described. To mitigate the deleterious effects of excess delay spread, the number of pilot subbands is greater than the cyclic prefix length. This “oversampling” may be achieved by using more pilot subbands in each symbol period or different sets of pilot subbands in different symbol periods. In one example, a first set of pilot subands may be received in a first symbol period, and a second set of pilot subands may be received in a second symbol period. The first set of pilot subands and the second set of pilot subbands may be staggered in frequency. | 12-02-2010 |
20100309861 | INTERFERENCE MITIGATION FOR DOWNLINK IN A WIRELESS COMMUNICATION SYSTEM - Techniques for mitigating interference in a wireless communication system are described. In an aspect, pertinent transmission parameters for a served UE may be sent to at least one interfered UE to support interference mitigation. In one design, information for at least one transmission parameter for a data transmission sent by a first cell to a first UE may be transmitted to at least one UE served by a second cell to enable the at least one UE to perform interference mitigation for the data transmission sent by the first cell to the first UE. The information may be transmitted by either the first cell or the second cell. In another aspect, a cell may send transmission parameters for a UE via a pilot. In yet another aspect, scrambling may be performed by a cell at symbol level to enable an interfered UE to distinguish between modulation symbols of desired and interfering transmissions. | 12-09-2010 |
20110064039 | MC-CDMA MULTIPLEXING IN AN ORTHOGONAL UPLINK - Techniques are provided to support multi-carrier code division multiple access (MC-CDMA) in an orthogonal uplink of a wireless communication system. A method of wireless multi-carrier communications comprises dividing sub-carriers on an uplink into non-overlapping groups, allocating a time-frequency block including a hopping duration and a non-overlapped group, respectively, assigning a different set of orthogonal codes to each user, spreading data (or pilot) symbols of each user over the allocated time-frequency block, wherein the data (or pilot) symbols of each user are spread using the different set of orthogonal codes assigned to each user, mapping each data (or pilot) symbol to a modulation symbol in the time-frequency block, generating an orthogonal waveform based on the mapped symbols, and transmitting the orthogonal waveform. | 03-17-2011 |
20110151790 | WIRELESS COMMUNICATION CHANNEL BLANKING - Systems and methodologies are described that facilitate blanking on portions of bandwidth, such as a subset of interlaces, utilized by communicating devices that are dominantly interfered by a disparate device in wireless communications networks. The portions of bandwidth can relate to critical data, such as control data, and one or more of the communicating devices can request that the dominantly interfering device blank on one or more of the portions. The communicating devices can subsequently transmit data over the blanked portions free of the dominant interference. Additionally, the dominantly interfering device can request reciprocal blanking from the one or more communicating devices. | 06-23-2011 |
20110235685 | MC-CDMA MULTIPLEXING IN AN ORTHOGONAL UPLINK - Techniques are provided to support multi-carrier code division multiple access (MC-CDMA) in an orthogonal uplink of a wireless communication system. A method of wireless multi-carrier communications comprises dividing sub-carriers on an uplink into non-overlapping groups, allocating a time-frequency block including a hopping duration and a non-overlapped group, respectively, assigning a different set of orthogonal codes to each user, spreading data (or pilot) symbols of each user over the allocated time-frequency block, wherein the data (or pilot) symbols of each user are spread using the different set of orthogonal codes assigned to each user, mapping each data (or pilot) symbol to a modulation symbol in the time-frequency block, generating an orthogonal waveform based on the mapped symbols, and transmitting the orthogonal waveform. | 09-29-2011 |
20110255518 | Use of supplemental assignments to decrement resources - Systems and methodologies are described that facilitate dynamically supplementing or decrementing resource assignments to mobile devices in a wireless network environment without requiring transmission of replacement assignments. Supplemental assignments can be generated based on information related to mobile device need and resource availability. Moreover, resource assignments can be persisted for a mobile device. | 10-20-2011 |
20110296279 | ROBUST ERASURE DETECTION AND ERASURE-RATE-BASED CLOSED LOOP POWER CONTROL - Techniques for performing erasure detection and power control for a transmission without error detection coding are described. For erasure detection, a transmitter transmits codewords via a wireless channel. A receiver computes a metric for each received codeword, compares the computed metric against an erasure threshold, and declares the received codeword to be “erased” or “non-erased”. The receiver dynamically adjusts the erasure threshold based on received known codewords to achieve a target level of performance. For power control, an inner loop adjusts the transmit power to maintain a received signal quality (SNR) at a target SNR. An outer loop adjusts the target SNR based on the status of received codewords (erased or non-erased) to achieve a target erasure rate. A third loop adjusts the erasure threshold based on the status of received known codewords (“good”, “bad”, or erased) to achieve a target conditional error rate. | 12-01-2011 |
20120002623 | SCALABLE FREQUENCY BAND OPERATION IN WIRELESS COMMUNICATION SYSTEMS - To support mobile stations that are not capable of demodulating the entire bandwidth or that can be made to demodulate less than the entire bandwidth, a system, apparatus and method are provided to schedule users on less than all of the bandwidth. Further, certain users can be scheduled on more of the bandwidth than others. | 01-05-2012 |
20120020354 | HIERARCHICAL CODING FOR MULTICAST MESSAGES - Techniques for sending signaling information using hierarchical coding are described. With hierarchical coding, individual messages for users are encoded using multiple interconnected encoders such that ( | 01-26-2012 |
20120089890 | FEC CODE AND CODE RATE SELECTION BASED ON PACKET SIZE - Techniques for encoding and decoding data are described. In an aspect, multiple code rates for a forward error correction (FEC) code may be supported, and a suitable code rate may be selected based on packet size. A transmitter may obtain at least one threshold to use for code rate selection, determine a packet size to use for data transmission, and select a code rate from among the multiple code rates based on the packet size and the at least one threshold. In another aspect, multiple FEC codes of different types (e.g., Turbo, LDPC, and convolutional codes) may be supported, and a suitable FEC code may be selected based on packet size. The transmitter may obtain at least one threshold to use for FEC code selection and may select an FEC code from among the multiple FEC codes based on the packet size and the at least one threshold. | 04-12-2012 |
20120093058 | MEHTOD AND APPARATUS FOR COMMUNICATION IN A SYSTEM EMPLOYING DIFFERING TRANSMISSION PROTOCOLS - A method and apparatus for communication in a system employing differing transmission protocols. It is determined whether a first time slot of one transmission protocol is adjacent to a second time slot of another transmission protocol, and if a first symbol within the first time slot is adjacent to a second symbol of the second time slot. A pilot power and/or a number of pilot sub-carriers or tones of the first symbol is increased and channel estimation is performed on the first symbol. | 04-19-2012 |
20120252468 | ADAPTIVE DISTRIBUTED FREQUENCY PLANNING - Systems and methodologies are described that facilitate employing distributed frequency planning and reuse factor optimization based upon forward link and/or reverse link interference management techniques. An optimal reuse factor for a base station can be determined based upon a metric that evaluates levels of service associated with neighboring base stations. Moreover, a subset of available resource sets can be selected for use by the base station; thus, a base station specific collection of resource sets can be formed through such selection. Further, mappings of each resource set to a set of physical resources can be disseminated in a network or portion thereof. According to another example, frequency hopping can be constrained to use of resources within a resource set (rather than across more than one resource set) as provided in a base station specific hopping pattern. | 10-04-2012 |
20120257687 | HIERARCHICAL CODING FOR MULTICAST MESSAGES - Techniques for sending signaling information using hierarchical coding are described. With hierarchical coding, individual messages for users are encoded using multiple interconnected encoders such that ( | 10-11-2012 |
20120287859 | SERVING BASE STATION SELECTION IN A WIRELESS COMMUNICATION NETWORK - 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. | 11-15-2012 |
20130142154 | DYNAMIC POWER AMPLIFIER BACKOFF USING HEADROOM INFORMATION - 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. | 06-06-2013 |
20130148557 | METHOD AND APPARATUS FOR ENHANCED DISCOVERY IN PEER-TO-PEER NETWORKS BY SYNCHRONIZED DISCOVERY WAKE UP - Certain aspects of the present disclosure relate to a technique for enhanced discovery in peer-to-peer (P2P) wireless network by synchronized discovery wake up. A wireless node can first obtain information about one or more time instants. Then, the wireless node can wake up to discover one or more other wireless nodes for communication, wherein the wake up occurs at the one or more time instants synchronized with the one or more other wireless nodes. The one or more time instants can be updated according to location information of the wireless node. | 06-13-2013 |
20130148642 | ENHANCED DISCOVERY PROCEDURES IN PEER-TO-PEER WIRELESS LOCAL AREA NETWORKS (WLANS) - Certain aspects of the present disclosure generally provide methods and apparatus for enhanced discovery procedures in peer-to-peer (P2P) wireless local area networks (WLANs). With these procedures, discovery duration may be decreased, battery power consumption may be reduced during discovery, provided services may be ascertained during the device discovery phase without performing a separate service discovery phase, and/or the discovery range may be extended in an effort to discover a greater number of devices. | 06-13-2013 |
20130148643 | ENHANCED DISCOVERY PROCEDURES IN PEER-TO-PEER WIRELESS LOCAL AREA NETWORKS (WLANS) - Certain aspects of the present disclosure generally provide methods and apparatus for enhanced discovery procedures in peer-to-peer (P2P) wireless local area networks (WLANs). With these procedures, discovery duration may be decreased, battery power consumption may be reduced during discovery, provided services may be ascertained during the device discovery phase without performing a separate service discovery phase, and/or the discovery range may be extended in an effort to discover a greater number of devices. | 06-13-2013 |
20130215778 | Intra-Cell Common Reuse for a Wireless Communication System - To avoid or reduce intra-cell interference, each sector of a cell is associated with a sector-specific set of system resources (e.g., subbands) and at least one non-overlapping common set of system resources. Each common set for each sector includes system resources observing little or no interference from at least one other sector in the cell. The channel condition for a terminal in a given sector x is ascertained based on forward and/or reverse link measurements for the terminal. The terminal is assigned system resources from a common set or a sector-specific set for sector x based on the terminal's channel condition. For example, if the terminal observes high interference from another sector y, then the terminal is assigned system resources from a common set that observes little or no interference from sector y. The techniques may be used for an OFDMA system that uses frequency hopping. | 08-22-2013 |
20130265968 | INTERFERENCE MITIGATION FOR CONTROL CHANNELS IN A WIRELESS COMMUNICATION NETWORK - Techniques for mitigating interference on control channels in a wireless communication network are described. In an aspect, high interference on radio resources used for a control channel may be mitigated by sending a request to reduce interference to one or more interfering stations. Each interfering station may reduce its transmit power on the radio resources, which may then allow the control channel to observe less interference. In one design, a user equipment (UE) may detect high interference on radio resources used for a control channel by a desired base station. The UE may send a request to reduce interference on the radio resources to an interfering base station, which may reduce its transmit power on the radio resources. The UE may receive the control channel on the radio resources from the desired base station and may observe less interference from the interfering base station. | 10-10-2013 |
20140223479 | APPARATUS AND METHODS OF PROVIDING AND RECEIVING VENUE LEVEL TRANSMISSIONS AND SERVICES - A venue-cast system and method for providing and receiving venue level transmissions and services, including discovery of a venue specific transmission by receiving an overhead signal from a non-venue network, extracting information for receiving the venue specific transmission from the overhead signal, and tuning to receive the venue specific transmission based on the extracted information. The venue level transmission may be provided and received in a manner that does not prevent an access terminal from receiving a local area or wide area transmission. | 08-07-2014 |
20140286317 | Assignment acknowledgement for a wireless communication system - A method, apparatus, and channel structure for acknowledging assignment messages is provided. The method and apparatus allow for efficient signaling based upon the resources. | 09-25-2014 |
20150055611 | METHOD AND APPARATUS FOR MITIGATING PILOT POLLUTION IN A WIRELESS NETWORK - Techniques for mitigating pilot pollution in a wireless network are described. In an aspect, pilot pollution may be mitigated by reducing density and/or transmit power of common pilots whenever possible. A cell may send a common pilot at a first density and a first transmit power level during a first time period and may send the common pilot at a second density and a second transmit power level during a second time period. The second density may be lower than the first density and/or the second transmit power level may be lower than the first transmit power level. Lower density may be achieved by sending the common pilot less frequently, on fewer subcarriers, and/or from fewer antennas. The cell may determine whether to reduce the density and/or transmit power of the common pilot based on network loading, SINRs of terminals, etc. In another aspect, pilot pollution may be mitigated by performing pilot cancellation at a terminal. | 02-26-2015 |