Patents by Inventor John Sadowsky

John Sadowsky has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 7881390
    Abstract: Methods and apparatus provide increased symbol length with more subcarriers in a fixed-bandwidth system. The subcarriers spacing may be reduced to provide increased symbol length and enable higher throughput. In one implementation, a system compatible with the IEEE P802.11n proposal can use 128 subcarriers in 20 MHz operation to provide increased throughput in lower-bandwidth channel operation.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: February 1, 2011
    Assignee: Intel Corporation
    Inventors: John Sadowsky, Alexander A. Maltsev, Vadim S. Sergeyev, Alexei V. Davydov
  • Publication number: 20090252257
    Abstract: A multiple-input-multiple output (MIMO) transmitter for transmitting an orthogonal frequency division multiplexed (OFDM) symbol over a plurality of spatial channels using a plurality of antennas is described. The transmitter includes encoding circuitry to encode blocks of input bits in accordance with a variable encoding rate to generate blocks of encoded bits and a spatial-frequency parser to parse the blocks of encoded bits into spatial-frequency groups. The transmitter also includes subcarrier modulators to modulate each spatial-frequency group of encoded bits on one of the OFDM subcarriers to generate symbol-modulated subcarriers. Spatial-frequency groups having a greater number of encoded bits are modulated at higher-order modulation levels and spatial-frequency groups having a lesser number of encoded bits are modulated at lower-order modulation orders.
    Type: Application
    Filed: June 11, 2009
    Publication date: October 8, 2009
    Inventors: John Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander A. Maltsev, Eric A. Jacobsen, Ali S. Sadri
  • Patent number: 7333555
    Abstract: Briefly, some embodiments of the invention may provide devices, systems and methods for wireless combined-signal communication. For example, a method in accordance with an embodiment of the invention may include transmitting a combined signal over a combined channel by mapping a first block of said combined signal to be carried by a first sub-channel of said combined channel and mapping a second block, substantially identical to said first block, to be carried by a second sub-channel of said combined channel.
    Type: Grant
    Filed: March 30, 2004
    Date of Patent: February 19, 2008
    Assignee: Intel Corporation
    Inventors: Gal Basson, Jorge Myszne, Yuval Finkelstein, Shay Waxman, Assaf Kasher, John Sadowsky
  • Publication number: 20080025430
    Abstract: In a multiple-input multiple-output (MIMO) system, multiple receive antennas produce a received signal vector, Y, which includes an element for each of the receive antennas. In an embodiment of a de-mapping method performed within a MIMO receiver, a quadrature phase shift keying (QPSK) search is performed within a search space that includes the full constellation of symbol points. Based on the results of the QPSK search, the search space is reduced to fewer than all of the quadrants, and the received signal vector data is scaled and transformed to the reduced search space. A lower-level QPSK search is performed, and the process is repeated until the modulation order is reduced to a QPSK constellation. Hard or soft decisions corresponding to the search results may then be passed to a decoder.
    Type: Application
    Filed: August 23, 2007
    Publication date: January 31, 2008
    Inventor: John Sadowsky
  • Publication number: 20060115012
    Abstract: Methods and apparatus provide increased symbol length with more subcarriers in a fixed-bandwidth system. The subcarriers spacing may be reduced to provide increased symbol length and enable higher throughput. In one implementation, a system compatible with the IEEE P802.11n proposal can use 128 subcarriers in 20 MHz operation to provide increased throughput in lower-bandwidth channel operation.
    Type: Application
    Filed: November 30, 2005
    Publication date: June 1, 2006
    Inventors: John Sadowsky, Alexander Maltsev, Vadim Sergeyev, Alexei Davydov
  • Publication number: 20060071807
    Abstract: In a communication system using closed loop MIMO, beam forming information may be fed back from a receiver to a transmitter sequentially over a number of frames. The beam forming matrices that are fed back may be quantized.
    Type: Application
    Filed: September 30, 2004
    Publication date: April 6, 2006
    Inventor: John Sadowsky
  • Publication number: 20060068777
    Abstract: Methods and systems for communicating in a wireless network include usage based switching between two or more different types of air interfaces. In example implementations, a first air interface for wireless wide area networks (WWAN) may be used for low bandwidth data transfers and a second interface for wireless local area networks (WLAN) or wireless metropolitan area networks (WMAN) may be used for higher bandwidth data transfers. Various specific embodiments and variations are also disclosed.
    Type: Application
    Filed: June 30, 2004
    Publication date: March 30, 2006
    Inventors: John Sadowsky, Ernest Woodward
  • Publication number: 20050220206
    Abstract: Briefly, some embodiments of the invention may provide devices, systems and methods for wireless combined-signal communication. For example, a method in accordance with an embodiment of the invention may include transmitting a combined signal over a combined channel by mapping a first block of said combined signal to be carried by a first sub-channel of said combined channel and mapping a second block, substantially identical to said first block, to be carried by a second sub-channel of said combined channel.
    Type: Application
    Filed: March 30, 2004
    Publication date: October 6, 2005
    Inventors: Gal Basson, Jorge Myszne, Yuval Finkelstein, Shai Waxman, Assaf Kasher, John Sadowsky
  • Publication number: 20050220199
    Abstract: Subcarrier phase rotation is implemented in an OFDM transmitting apparatus to overcome problems such as, for example, non-frequency selective multipath fading. In at least one embodiment, subcarrier phase rotation is practiced in an OFDM system implementing multiple input multiple output (MIMO) techniques.
    Type: Application
    Filed: March 31, 2004
    Publication date: October 6, 2005
    Inventors: John Sadowsky, Shmuel Levy, Sumeet Sandhu, Keith Holt
  • Publication number: 20050174927
    Abstract: Methods and systems for communicating in a wireless network may distinguish different types of packet structures by modifying the phase of a modulation constellation, such as a binary phase shift keying (BPSK) constellation, in a signal field. Receiving devices may identify the type of packet structure associated with a transmission or whether the signal field is present by the phase of the modulation constellation used for mapping for the signal field. In one embodiment, the phase of the modulation constellation may be determined by examining the energy of the I and Q components after Fast Fourier Transform. Various specific embodiments and variations are also disclosed.
    Type: Application
    Filed: December 20, 2004
    Publication date: August 11, 2005
    Inventors: Adrian Stephens, John Sadowsky
  • Publication number: 20050152473
    Abstract: A frame structure for communicating over a high-throughput communication channel includes a channelization field as part of a current data unit to indicate a frequency and space configuration of subsequent portions of the current data unit.
    Type: Application
    Filed: March 26, 2004
    Publication date: July 14, 2005
    Inventors: Alexander Maltsev, Ali Sadri, Vadim Sergeyev, Adrian Stephens, John Sadowsky
  • Publication number: 20050147076
    Abstract: In an orthogonal frequency division multiplexed (OFDM) system, a transmitter and/or receiver communicate separate data streams on non-orthogonal spatial channels. Each spatial channel may use the same set of OFDM subcarriers and may take advantage of the multipath characteristics of the spatial channel allowing the communication of additional data without an increase in frequency bandwidth. Space-frequency subcarrier modulation assignments may be dynamically assigned on a per subcarrier basis as well as a per spatial channel basis to help maximize the data-carrying capacity of the channel. In some embodiments, each of the spatial channels may be associated with one of a plurality of spatially diverse antennas. In other embodiments, beamforming may be performed to allow the transmission and/or reception of signals within the spatial channels.
    Type: Application
    Filed: December 29, 2003
    Publication date: July 7, 2005
    Inventors: John Sadowsky, Minnie Ho, Sumeet Sandhu, Alexander Maltsev, Eric Jacobsen, Ali Sadri
  • Publication number: 20050141644
    Abstract: In a multiple-input multiple-output (MIMO) system, multiple receive antennas produce a received signal vector, Y, which includes an element for each of the receive antennas. In an embodiment of a de-mapping method performed within a MIMO receiver, a quadrature phase shift keying (QPSK) search is performed within a search space that includes the full constellation of symbol points. Based on the results of the QPSK search, the search space is reduced to fewer than all of the quadrants, and the received signal vector data is scaled and transformed to the reduced search space. A lower-level QPSK search is performed, and the process is repeated until the modulation order is reduced to a QPSK constellation. Hard or soft decisions corresponding to the search results may then be passed to a decoder.
    Type: Application
    Filed: December 31, 2003
    Publication date: June 30, 2005
    Inventor: John Sadowsky
  • Publication number: 20050111345
    Abstract: Methods, apparatus and systems are disclosed for block encoding/decoding information wireless networks having narrow decoding latency restrictions. A method includes identifying a length of information to be sent in a block code and encoding the information to be sent in the block code into one or more codewords, where the number of codewords and the amount of information encoded within each codeword is adjusted based on the identified length and to achieve a similar codeword error probability for each codeword considering available decoding time for decoding a last codeword is less than available decoding time for decoding a first codeword. In certain implementations low density parity check (LDPC) encoding may be used in combination with OFDM to provide reliable communications in a high throughput WLAN.
    Type: Application
    Filed: November 25, 2003
    Publication date: May 26, 2005
    Inventors: Eric Jacobsen, John Sadowsky
  • Patent number: 5933082
    Abstract: The device assists those who are visually handicapped and, in particular, warns blind or visually impaired travellers that they have entered a potentially dangerous area proximal to the edge of boarding platforms of the type typically found in public railway transit systems. An InfraRed Integrated Information System consists of an array of infrared transmitters and a portable detector/warning device to be held by the blind traveller. The transmitters create a beam of infrared light which bathes the section of the platform proximal to the platform edge. As the traveller moves into the region of the platform covered by the emission, the sensors in the warning device are activated and by audio, tactile or other stimuli alert the traveller of entry into the danger zone.
    Type: Grant
    Filed: April 2, 1996
    Date of Patent: August 3, 1999
    Assignee: The Johns Hopkins University
    Inventors: Joseph Lawrence Abita, John Sadowsky, Wolfger Schneider, Robert W. Massof