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Sandip Sarkar, San Diego US

Sandip Sarkar, San Diego, CA US

Patent application numberDescriptionPublished
20080232294METHOD AND APPARATUS FOR DISTINGUISHING BROADCAST MESSAGES IN WIRELESS SIGNALS - Methods and apparatus for processing and generating broadcast messages determined by a subband and OFDM symbols of frames in which signals are received. Overhead messages indicating resources used by broadcast messages in a wireless communication system are generated. Signals are received over a wireless system and broadcast messages are determined from the signals as designated by a subband and OFDM symbols of frames of an ultraframe in which signals are received.09-25-2008
20080261582METHOD AND APPARATUS FOR USING A MAC PROTOCOL FOR BROADCAST - Method and apparatus that provide for broadcast multicast services in an ultra mobile broadband network are disclosed. A broadcast transmission structure provides for efficient indexing of subbands reserved for BCMCS. Transmissions on the logical channels are segmented into error control blocks beginning with zero or one MAC packet received by a MAC layer. A transmitting entity appends parameters relating to content change within a next ultraframe at end of every broadcast packet that is not a stuffing packet. A mapping message of multiple Physical Layer groups addresses a single logical channel when SFN (Single Frequency Network) coverage of an associated subband group is different from SFN coverage of the logical channel.10-23-2008
20090046570EIGEN-BEAMFORMING FOR WIRELESS COMMUNICATION SYSTEMS - Techniques for sending multiple-input multiple-output (MIMO) transmissions in wireless communication systems are described. In one design, a transmitter sends a first reference signal via a first link, e.g., a cell-specific reference signal via the downlink. The transmitter receives channel quality indicator (CQI) information determined by a receiver based on the first reference signal. The transmitter also receives a second reference signal from the receiver via a second link, e.g., a sounding reference signal via the uplink. The transmitter obtains at least one MIMO channel matrix for the first link based on the second reference signal. The transmitter determines at least one precoding matrix based on the at least one MIMO channel matrix, e.g., in accordance with ideal eigen-beamforming or pseudo eigen-beamforming. The transmitter then sends a data transmission to the receiver based on the at least one precoding matrix and the CQI information.02-19-2009
20090046582BEAMFORMING OF CONTROL INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - Techniques for sending traffic data and control information in a wireless communication system are described. In one design, a transmitter (e.g., a Node B or a UE) may perform beamforming to send traffic data on M layers based on a precoding matrix, where M may be one or greater. The transmitter may also perform beamforming to send control information on up to M layers based on the same precoding matrix used for the traffic data. The transmitter may send the beamformed traffic data on a first physical channel and may send the beamformed control information on a second physical channel. The transmitter may multiplex the beamformed traffic data and the beamformed control information using time division multiplexing (TDM) or frequency division multiplexing (FDM).02-19-2009
20090054093ANTENNA SWITCHING AND UPLINK SOUNDING CHANNEL MEASUREMENT - Systems and methodologies are described that facilitate employing downlink precoding based on uplink sounding channel measurement and channel reciprocity in time division duplex or time division multiplex systems. In particular, mechanism are provided that enable downlink precoding in situations where user equipment antenna configuration includes an unequal number of transmit chains and receive chains. A mobile device transmits modulated sounding reference signals on each antenna during a calibration stage. The mobile device then transmits non-modulated sounding reference signals during a normal mode. A base station utilizes the modulated and non-modulated sounding reference signals to restore a downlink channel estimate employed in downlink precoding.02-26-2009
20090083602OPERATION OF A FORWARD LINK ACKNOWLEDGEMENT CHANNEL FOR THE REVERSE LINK DATA - An acknowledgement method in a wireless communication system. Initially, a reverse supplemental channel (R-SCH) frame is received at a base station. The base station then transmits an acknowledgement (ACK) signal if quality of the received R-SCH frame is indicated as being good. A negative acknowledgement (NAK) signal is transmitted only if the received data frame is indicated as being bad but has enough energy such that, if combined with energy from retransmission of the data frame, it would be sufficient to permit correct decoding of the data frame. If the best base station is known, the acknowledgement method may reverse the transmission of the acknowledgement signals for the best base station so that only NAK signal is sent. A positive acknowledgement is assumed in the absence of an acknowledgement. This is done to minimize the transmit power requirements.03-26-2009
20090093222CALIBRATION AND BEAMFORMING IN A WIRELESS COMMUNICATION SYSTEM - Techniques for performing calibration and beamforming in a wireless communication system are described. In an aspect, a Node B may periodically perform calibration in each calibration interval with a set of UEs to obtain a calibration vector for the Node B. The Node B may apply the calibration vector to account for mismatches in the responses of the transmit and receive chains at the Node B. In another aspect, the Node B may perform beamforming to a UE by taking into account gain imbalance for multiple antennas at the UE. The Node B may determine a precoding matrix for beamforming by taking into account gain imbalance due to (i) different automatic gain control (AGC) gains for receive chains at the UE, (ii) different power amplifier (PA) gains for transmit chains at the UE, and/or (iii) different antenna gains for multiple antennas at the UE.04-09-2009
20090129259CODING AND MULTIPLEXING OF CONTROL INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - Techniques for sending control information in a wireless communication system are described. In an aspect, a UE spreads control information across frequency with a DFT and across time with an orthogonal sequence to obtain output data for the control information. In one design, the UE receives codewords for N HARQ processes in N downlink subframes, determines an ACK value for each HARQ process, codes N ACK values for the N HARQ processes to obtain ACK information, generates output data for the ACK information, and sends the output data in one of M uplink subframes. In another aspect, first control information is processed based on a first coding and multiplexing scheme utilizing code division multiplexing in time and frequency domains. Second control information is processed based on a second coding and multiplexing scheme utilizing code division multiplexing in time domain and spreading in frequency domain.05-21-2009
20090129298EFFICIENT SYSTEM IDENTIFICATION SCHEMES FOR COMMUNICATION SYSTEMS - Systems and methodologies are described that facilitate efficiently indicating parameter(s) associated with a base station utilizing synchronization signals in a wireless communication environment. For instance, relative locations of a PSC and a SSC in a radio frame can be a function of a parameter. Further, a PSC sequence utilized to generate PSCs can be selected based upon a parameter. Moreover, inclusion or exclusion of PSCs from a radio frame can be a function of a parameter. Additionally or alternatively, pseudo random sequence mappings (e.g., to cell IDs, tone locations) can be a function of a parameter. Example parameters can be whether the base station is part of a TDD or a FDD system, whether the radio frame employs FS05-21-2009
20090143072CONTROL ARRANGEMENT AND METHOD FOR COMMUNICATING PAGING MESSAGES IN A WIRELESS COMMUNICATION SYSTEM - Systems and methods for utilizing paging group IDs and paging indicators are disclosed for PDCCH and PDSCH transmissions to mobile terminals in a mobile communication system. By use of the paging group IDs and paging indicators, various groups of mobile terminals, including subsets of those groups can be paged with reduced decoding requirements. Nesting of the grouping is exploited and packing of the PDCCH frame to accomplish efficient use is described.06-04-2009
20090168922METHODS AND SYSTEMS FOR PDCCH BLIND DECODING IN MOBILE COMMUNICATIONS - Various methods and systems for efficiently performing the blind decoding of downlink signals is described. Several forms of arranging possible CCE combinations are examined and investigated. Based on PDCCH size estimation/information, CCE concatenations that are most likely (of limited sets) can be arrived at. Tree-based concatenations are also devised using largest CCE ordering to align smaller CCE sizes to similar boundaries. By such ordering, the search space for all possible CCE ordering and sizes can be reduced to an efficient tree. Set mapping between possible lnposelstartCCElnposelend/REs are also described using a first set to secondary and tertiary sets. Various other ordering and sorting schemes are also detailed that enable a blind decode of a PDCCH channel to be efficiently performed.07-02-2009
20090180435TDD OPERATION IN WIRELESS COMMUNICATION SYSTEMS - A method provides a wireless frame protocol. The method includes communicating a transmission interval that facilitates switching between a downlink portion and an uplink portion of a wireless communications channel. The method employs one or more guard periods during the transmission interval to mitigate overlap of transmitting frequencies between the downlink and uplink portions of the wireless communications channel.07-16-2009
20090274100UPLINK RESOURCE MANAGEMENT IN A WIRELESS COMMUNICATION SYSTEM - Management of uplink resources in a wireless communication is presented. In one embodiment, management of uplink resources comprises receiving a multi-bit acknowledge (multi-bit A/N) that is available for uplink transmission and receiving other information that is available for uplink transmission along with the multi-bit A/N. Next, it is determined whether a condition has been met. If the condition has been met, an uplink message is created comprising the multi-bit A/N but dropping the other information. If the condition has not been met, an uplink message is created which jointly codes the multi-bit A/N and the other information. The uplink message is then transmitted to a receiver.11-05-2009
20090279460BUNDLING OF ACK INFORMATION IN A WIRELESS COMMUNICATION SYSTEM - Techniques for bundling acknowledgement (ACK) information in a wireless communication system are described. In one design, a user equipment (UE) may receive multiple codewords in at least one downlink subframe. The UE may decode the multiple codewords and determine an ACK or a negative acknowledgement (NACK) for each codeword based on decoding result. The UE may bundle the ACKs and NACKs for the multiple codewords to obtain bundled ACK information. In one design, the UE may generate (i) a bundled ACK if ACKs are obtained for all codewords or (ii) a bundled NACK if a NACK is obtained for any codeword. The UE may send the bundled ACK information as feedback for the multiple codewords. The UE may receive retransmissions of the multiple codewords if a bundled NACK is sent and may receive new codewords if a bundled ACK is sent.11-12-2009
20090279500METHODS OF SENDING CONTROL INFORMATION FOR USERS SHARING THE SAME RESOURCE - Certain aspects of the present disclosure relate to a method for sending control information to multiple user terminals that share the same resources in a Spatial Division Multiple Access (SDMA) wireless system. The control information can be transmitted from an access point over a physical downlink control channel (PDCCH) that is common for a plurality of user terminals. The overall PDCCH overhead can thus be reduced due to a smaller number of required PDCCH in the SDMA wireless system.11-12-2009
20090285267METHOD AND APPARATUS FOR MAXIMIZING STANDBY TIME IN REMOTE STATIONS CONFIGURED TO RECEIVE BROADCAST DATABURST MESSAGES - A wireless telecommunications system includes a base station, a plurality of remote stations, a first channel for general page messages containing paging information and broadcast databurst message references, and an auxiliary channel for broadcast databurst notification indicators for the purpose of increasing standby time in remote stations configured to receive broadcast databurst messages.11-19-2009
20100034163ANCHOR CARRIER IN A MULTIPLE CARRIER WIRELESS COMMUNICATION SYSTEM - Multiple downlink (DL) and uplink (UL) carriers can enhance wireless communication between nodes and user equipment (UE). Among the carriers, it is beneficial to have some special, by configuration designated carriers to provide synchronization, system information, paging, data and control for multi-carrier enabled UEs. Thereby, overhead system information can be reduced. For instance, synchronization and paging for a certain cell are not provided on all carriers. A carrier can provide backward compatibility for single carrier UEs for access, synchronization, broadcast, and new control region within the data region of the legacy terminals. Coordination between nodes for selecting anchor carriers that mitigate interference and for transmit power control for non-anchor carriers provide further network performance advantages.02-11-2010
20100034303DOWNLINK GRANTS IN A MULTICARRIER WIRELESS COMMUNICATION SYSTEM - Aspects describe communicating grant information in a multicarrier wireless communication system. The grant information can be transmitted to mobile devices that have single carrier capability and/or mobile devices that have multicarrier capability. Grant information can be sent in a legacy control region and/or a non-legacy control region.02-11-2010
20100035625MULTI-CARRIER DESIGN FOR CONTROL AND PROCEDURES - A method, an apparatus, and a computer program product operable in a wireless communication system are provided in which a pairing is determined between one or more uplink carriers and one or more downlink carriers. The one or more uplink carriers and the one or more downlink carriers include at least three carriers. On which carrier to exchange control information on one or more of the carriers is based on the pairing or an anchor carrier designation.02-11-2010
20100040004MULTI-CARRIER GRANT DESIGN - Systems and methodologies are described that facilitate assigning resources for an anchor carrier and an additional carrier with a grant message. The grant message communicated with an anchor carrier can include resource information a plurality of carriers. Moreover, the systems and methodologies that facilitate identifying control information for an anchor carrier and/or an additional carrier based upon an operating mode, wherein the operating mode is a legacy mode or an extended mode. Based on the operating mode, particular resources associated with control regions are monitored for control information for respective anchor carrier(s) or additional carrier(s).02-18-2010
20100062783TRANSMISSION AND RECEPTION OF DEDICATED REFERENCE SIGNALS - Providing a coding scheme for wireless communication downlink reference signals is described herein. By way of example, a dedicated reference signal is mapped to resources of a wireless channel as a function of an identifier (ID) of a cell in which the reference signal is transmitted. The function can be similar to mapping functions employed for common reference signals, or can be distinct from such functions. As one example of the latter, a dedicated reference signal mapping function can be shifted in time or frequency with respect to the common reference signal mapping function. By employing a mapping function based on cell ID, noise caused by concurrent transmission of reference signals can be mitigated in a manner readily determined by terminals in a wireless network.03-11-2010
20100135156CONGESTION CONTROL IN A WIRELESS DATA NETWORK - Techniques for congestion control are disclosed. In an embodiment, a base station allocates a shared resource using a combination of zero or more individual grants and zero or more common grants, and generates a multi-valued busy signal in response to loading conditions that exceed a pre-determined level. In another embodiment, a subset of transmitting mobile stations reduce their transmission rate in response to a multi-valued busy signal. The subset may include autonomous transmission, commonly granted transmission, individually granted transmission, or any combination thereof. In various embodiments, rate adjustment may be probabilistic or deterministic. In an embodiment, a rate table is deployed, and a mobile station decreases or increases the transmission rate from one rate in the table to a lower or higher rate in the table, respectively, in response to the busy signal. Various other aspects provide efficient congestion control, avoiding excessive interference and increasing capacity.06-03-2010
20100182957APPARATUS, SYSTEM, AND METHOD FOR MANAGING REVERSE LINK COMMUNICATION - An apparatus, system, and method efficiently manage reverse link resources by allowing a mobile station to select between transmitting a payload at a standard power level and transmitting a smaller payload at a boosted power level. The mobile station, therefore, can autonomously select a QoS (Quality of Service) level for physical layer packets. Based on reverse link transmission information received from a base station, the mobile station derives a reverse link transmission guideline defining the power levels and associated payloads for at least a standard service and boosted service. The mobile station selects a reverse link transmission power level from a plurality of power levels including at least a standard reverse link transmission power level associated with a standard payload size and a boosted reverse link transmission power level associated with a boosted payload size where the standard payload size is greater than the boosted payload size.07-22-2010
20100232318RANDOM ACCESS CHANNEL (RACH) OPTIMIZATION FOR A SELF-ORGANIZING NETWORK (SON) - Systems and methodologies are described that facilitate optimizing parameters for random access in a wireless communication environment. A network manager can select centrally optimized parameters for random access that mitigate interference among RACH attempts and/or mitigate uplink interference due to RACH in a SON. Moreover, a base station can select locally optimized parameters for random access that mitigate a number of access attempts, mitigate interference among RACH attempts, and/or mitigate uplink interference due to RACH. The centrally optimized parameters can include PRACH configurations, root sequence parameters, ranges for one or more MAC parameters (e.g., initial transmit power, power ramp step, maximum number of preamble transmissions, contention resolution timer, . . . ), and so forth. Further, the locally optimized parameters can include sequence length, one or more MAC parameters (e.g., initial received target power of the random access preamble, power ramp step, contention resolution timer, maximum number of preamble transmissions, . . . ), etc.09-16-2010
20100260081BANDWIDTH SEGMENTATION AND MULTI-SEGMENT OPERATION AND CONTROL - Bandwidth segmentation according to a one carrier approach conveyed in a main information block (MIB) supports a plurality of contiguous frequency segments with one frequency segment seen by legacy terminals and the whole bandwidth seen by advanced terminals. Control regions either within data regions of a legacy frequency band segment or with one or two contiguous advanced frequency band segments separated by the legacy frequency band segment are communicated to advanced terminals in system information blocks (SIBs) or conveyed to an advanced UE by dedicated signaling.10-14-2010
20110007756CHANNEL ALLOCATIONS IN A COMMUNICATIONS SYSTEM - Systems and techniques for communications include forming a data packet, selecting a plurality of transmission parameters for the data packet, generating information having one of a plurality of codes identifying the transmission parameters, and transmitting the data packet on a first channel and the information on a second channel. It is emphasized that this abstract is provided to comply with the rules requiring an abstract which will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or the meaning of the claims.01-13-2011

Patent applications by Sandip Sarkar, San Diego, CA US