Sony Corporation

Qualcomm Incorporated

Sony Electronics Inc

Other

Joseph C Chan

Matthias Brehler

James E Beckman

Michael Leviant

Robert L Dorney

Brian Clarke Banister

Supratik Bhattacharjee

Farrokh Abrishamkar

Jeremy M Stein

Chinh Viet Tran

Chi-ping Nee

Raheel Khan

Shivratna Giri Srinivasan

Koji Kimura

Naveed U Zaman

Ron Shalev

Wireless receiver circuits and methods include algorithms for switching between a least-squares/minimum mean-square error method of channel estimation known as the CE algorithm, and a continuous plot method of channel estimation known as the CPCE algorithm based upon channel characteristics to improve reception of wireless communications in different reception conditions. In an embodiment, the CPCE algorithm may be selected by a processor for use in channel estimation when a calculated number of candidate paths is less than or equal to a first threshold value, a calculated power ratio of the L strongest paths to the total of all paths is greater than or equal to a second threshold value, and the maximum Automatic Gain Control variation is greater than or equal to a third threshold value. Threshold values may be based on field testing, and set to values at which the CE or CPCE algorithm exhibits better performance.

Methods and systems for improved channel estimation in multi-carrier systems

Techniques for deriving a channel estimate using a scattered pilot and a continual pilot are described. The scattered pilot is sent on different sets of carriers in different symbol periods. The continual pilot is sent in each symbol period on irregularly spaced carriers. The scattered pilot is used to identify the indices of channel taps of interest, e.g., L strongest channel taps. The continual pilot is used to determine the complex gains of these L channel taps. A receiver derives a channel impulse response estimate based on received pilot symbols for the scattered pilot, identifies the L strongest channel taps, and determines the indices of these L strongest channel taps. The receiver forms a Fourier sub-matrix based on the L tap indices and determines the gains of the L channel taps based on received pilot symbols for the continual pilot and the Fourier sub-matrix.

Channel estimation for multi-carrier communication

An apparatus and method for processing signals are disclosed. The apparatus may include a transceiver configured to receive a first paging signal during a first cycle, a memory, and a processor configured to store the received first paging signal in the memory, to switch the transceiver to an off state after the first paging signal is stored in the memory, and to process the stored first paging signal while the transceiver is in the off state.

Device, method, and apparatus for offline discontinuous reception (DRX) processing in cellular systems

Techniques are provided which may be implemented in various methods and/or apparatuses that to provide a tasking system buffer interface capability to interface with a plurality of shared processes/engines.

Tasking system interface methods and apparatuses for use in wireless devices

Apparatus and methods are provided for making timing adjustments in a multi carrier communications system. In an aspect, a timing correction method is provided for a multi-carrier system. This includes adjusting the time basis of two or more pilot interlaces with respect to each other in order to account for timing differences between the interlaces when combining the interlaces, and then adjusting or matching the time bases of the combined interlaces with a symbol to be demodulated. The alignment and matching is performed in order to generate channel estimates for data demodulation. The channel estimates, thus generated, along with the timing alignment information are in turn used for determining timing corrections to be applied to demodulation of a particular symbol. Corresponding apparatus are also disclosed that implement the methodology.

Timing adjustments for channel estimation in a multi carrier system

A bit error position is estimated. The estimation method includes generating data indicative of a substantial number of bit error locations in data frames. The generation of the data includes re-encoding decoded bit stream, mapping the bit stream to a first set of symbols, and determining a soft decision distance between a second set of symbols received through a data transmission channel and the first set of symbols. The generated data is then used to estimate the bit error locations. The estimation process includes capturing metric data for each bit in the data frame and obtaining derivative of the metric data. The derivative may be filtered for further processing. Error position estimation criteria may then be applied to estimate the bit error positions.

Bit error position estimation in data decoder

A method for concealing errors in texture partition of a video packet is described. The method includes determining a particular macroblock within the texture partition where error is detected, concealing the error starting at the particular macroblock, and evaluating image smoothness of concealed macroblocks. The concealing and evaluating are repeated with one more macroblock added prior to the previous particular macroblock. The concealing and evaluating are repeated until all macroblocks in the texture partition have been concealed. A set of macroblocks, including a combination of decoded and concealed macroblocks, that produces best image smoothness is then selected to replace the corrupted texture partition.

Error concealment of video data using texture data recovery

A method and apparatus for initial acquisition using an adaptive threshold includes performing a sort operation of a plurality of full-length correlator outputs and updating the adaptive threshold. Partial-length correlator outputs are generated and compared with an adaptive threshold. If a partial-length correlator output for a particular PN sequence timing is greater than or equal to the adaptive threshold, a full-length correlator output for that PN sequence timing is generated. A sort operation of a plurality of full-length correlator outputs is performed, and sort results are used to update the adaptive threshold. If a partial-length correlator output for a particular PN sequence timing is less than the adaptive threshold, a full-length correlator output for that PN sequence timing is not generated.

Method and apparatus for using adaptive threshold with initial acquisition

The present invention provides several methods and apparatuses for varying the size of a radiolink protocol (RLP) packet based on channel condition estimation. According to one aspect, a channel condition metric is generated to indicate a channel condition. The channel condition metric is processed to determine the optimal packet-size for the channel condition. An optimal RLP packet-size that corresponds to the processed channel condition metric is chosen. All the optimal RLP packets that are control type are equipped with CRC bits and sent to the requester. Sending an optimal RLP packet helps maximize system throughput and adding CRC bits to the control type RLP packets prevents the RLP packet from getting rejected due to bit errors.

Method and apparatus for variable frame size radiolink protocol based on channel condition estimation

A method for concealing errors in video data is disclosed. The method includes decoding a first set of motion vectors and estimating a second set of remaining motion vectors in the corrupted video packet. A motion compensated temporal replacement of texture data is performed using the first and second sets of motion vectors. The image smoothness of the texture data is then performed. The decoding, estimating, performing temporal replacement, and evaluating are repeated with one less motion vector in the first set and one more motion vector in the second set. The repeating is done until there is no more motion vector left in the first set. Sets of motion vectors that produce a best image smoothness measure of the texture data are selected from the first and second sets.

Error concealment of video data using motion vector data recovery

A method and apparatus for entering characters with a reduced number of key presses. The sequence of one or more previously entered characters is used to select a character assignment matrix. The order of characters in the assignment matrix is determined by the probability that the letter will be the next in the sequence, with more likely characters being presented first. Repeated key presses are used to access characters with lower probability.

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San Diego, CA, United States of America

Joseph C Chan