Qualcomm Incorporated

Other

Tao Tian

Vijayalakshmi Rajasundaram Raveendran

Peisong Chen

Fang Shi

Bin Tian

Gordon Kent Walker

Phanikumar Kanakadurga Bhamidipati

Sameer Vermani

Lin Yang

Raghuraman Krishnamoorthi

Seyfullah Halit Oguz

Fuyun Ling

Krishna Kiran Mukkavilli

Gwendolyn Denise Barriac

Dhananjay Ashok Gore

Michael Mao Wang

Sitaraman Ganapathy Subramania

Jing Jiang

Rahul Tandra

Dung Ngoc Doan

Thomas Sun

Eric Pierre Rebeiz

Sitaraman Ganapathy Subramanian

Yan Zhou

Simone Merlin

Alfred Asterjadhi

James Arthur Proctor, Jr

Ashok Mantravadi

Steven J Howard

Didier Johannes Richard Van Nee

Albert Van Zelst

Fang Liu

Amit Rohatgi

Scott T Swazey

Hemanth Sampath

Kenneth Marvin Gainey

Murali Chari

Bojan Vrcelj

Seong Taek Chung

Vinay Murthy

Yuheng Huang

Hakan Inanoglu

Tadeusz Jarosinski

Eugene Jong-Hyon Baik

Serafim S Loukas

Kent Gordon Walker

Xinmiao Zhang

Didier Johannes Van Nee

Gordon Kent Qualcomm Incorporated Walker

Phanikumar Bhamidipati

Phanikumar Qualcomm Incorporated Bhamidipati

Aspects of the present disclosure provide techniques for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations.

Phase tracking in training fields

A method of wirelessly communicating a packet includes generating, at a first wireless device, a first packet including a first preamble decodable by a plurality of devices and a second preamble decodable by only a subset of the plurality of devices. The first preamble includes a first signal field. The second preamble includes a first training field. The method further includes transmitting the first packet concurrently with one or more second packets to be transmitted by wireless devices other than the first wireless device.

Methods and apparatus for packet acquisition in mixed-rate wireless communication networks

A method of wirelessly communicating includes generating, at a wireless device, a packet including a first preamble field. The method further includes generating a first repeated preamble field by multiplying the first preamble field by a first frequency-domain polarity sequence. The method further includes transmitting the packet from the wireless device. The packet includes the first preamble field and the first repeated preamble field.

Robust early detection through signal repetition in mixed-rate wireless communications

Techniques are provided for phase tracking in wireless communications using frames with some portions that use relatively long symbol durations. One technique includes generating a frame having a plurality of orthogonal training field sequences. Each orthogonal training field sequence is assigned to a different spatial stream. The frame is output for transmission as a single user (SU) transmission, a downlink multi-user (MU) multiple input multiple output (MIMO) transmission, or an orthogonal frequency division multiple access (OFDMA) transmission. After obtaining the frame, channel estimation and/or phase tracking may be performed based on the orthogonal training field sequences.

Orthogonal training field sequences for phase tracking

A method of wirelessly communicating a packet including a first portion for transmission over at least one channel of a first transmission type and a second portion for transmission over at least one channel of a second transmission type. In one aspect, the method includes generating, at a wireless device, a packet including a first portion having a first symbol duration. The packet further includes a second portion having a second symbol duration greater than the first. The second portion can include a plurality of repeated portions of the signal field, the repeated portions having the second symbol duration. The first portion includes a first training field. The method further includes prepending or appending a second training field to the first portion. The second training field has the second symbol duration. The method further includes transmitting the packet.

Aspects of the present disclosure provide example preamble formats with repeated signal (SIG) fields that may help provide backwards compatibility and help address the effects of larger delay spreads in various wireless bands (e.g., WiFi bands).

High efficiency WLAN preamble structure

Systems and methods for using travelling pilots for channel estimation are described herein. In one aspect, wireless communications apparatus is described that comprises a processor configured to divide a plurality of tones on which pilot signals are to be transmitted among a plurality of symbols, wherein each symbol includes less than all of the plurality of tones and the plurality of symbols includes at least a subset of the plurality of tones. The wireless communication apparatus further comprises a transmitter configured to transmit, during a given symbol, pilot signals on the tones included in the given symbol, wherein the tones over which the pilot signals are transmitted are changed from symbol to symbol.

Systems and methods for transmitting pilot tones

A method of processing a sequence of frames of multimedia data is presented. The method provides for progressively refreshing the image data. The method includes dynamically selecting portions of frames of the sequence with progressively increasing area to refresh, and excluding non-refreshed areas as potential reference data for other frames.

Method and apparatus for progressive channel switching

Certain aspects of the present disclosure provide methods and apparatus for detecting ongoing transmissions and assessing channel state, based on midpacket detection. One example method generally includes receiving signals on a primary channel; detecting, based on the received signals, occurrence or non-occurrence of a first ongoing packet transmission on a primary channel; and generating at least one of a busy signal or an idle signal based on the detection. In this manner, collisions may be avoided.

Midpacket detection schemes for clear channel assessment (CCA)

A method and apparatus for tracking amplitude and phase of a received low frequency signal comprising a walking pilot signal is disclosed, wherein the pilot signal changes in frequency a number of times according to a sequence that repeats. The design includes initializing a FIFO buffer and summing estimated channel power over the sequence to determine an initial total power. The design also includes, for a new received symbol, determining an updated power estimate for the new received symbol, placing the updated power estimate in the FIFO buffer, and removing a least current value from the FIFO buffer, and estimating amplitude of the signal using a sum of all updated power estimates in the FIFO buffer divided by the initial total power. The design may further include determining a delta phase value using maximum ratio combining scaled with a scaling factor.

Phase and amplitude tracking in the presence of a walking pilot signal

The invention generally relates to multimedia data processing, and more particularly, to processing operations performed prior to or in conjunction with data compression processing. A method of processing multimedia data includes receiving interlaced video frames, obtaining metadata for the interlaced video frames, converting the interlaced video frames to progressive video using at least a portion of the metadata; and providing the progressive video and at least a portion of the metadata to an encoder for use in encoding the progressive video. The method can also include generating spatial information and bi-directional motion information, for the interlaced video frames, and generating progressive video based on the interlaced video frames using the spatial and bi-directional motion information.

Preprocessor method and apparatus

Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes classifying content of multimedia data, and encoding the multimedia data in a first data group and in a second data group based on the content classification, wherein the first data group comprises a coefficient and the second data group comprises a first differential refinement associated with the first data group coefficient. An apparatus for using content information for encoding multimedia data includes a content classifying module configured to classify content of multimedia data and provide content classification data, and an encoder configured to encode the multimedia data in a first data group and in a second data group based on the content classification, wherein the first data group comprises a coefficient and the second data group comprises a first differential refinement associated with the first data group coefficient.

Scalability techniques based on content information

Apparatus and methods of using content information for encoding multimedia data are described. A method of processing multimedia data includes classifying content of multimedia data, and encoding the multimedia data in a first data group and in a second data group based on the content classification. The first and second groups are associated with quality levels. A user can request a target quality level.

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San Diego, CA, United States of America

Tao Tian