Patents by Inventor Stephen A. Allpress

Stephen A. Allpress 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: 9369310
    Abstract: An apparatus, method and program for processing a signal received over a wireless channel. The apparatus comprises: a channel searcher configured to determine a profile of the channel in the form of energy values for a plurality of rays at respective channel positions, and an equalizer for equalizing the signal based on a variable window of the equalizer. The channel searcher is configured to estimate dispersion of the channel by determining a measure of variance of ray distance from a reference position within the channel profile weighted by ray energy. The equalizer is coupled to the channel searcher and arranged to adapt the window in dependence on the measure of energy-weighted ray distance variance.
    Type: Grant
    Filed: January 13, 2012
    Date of Patent: June 14, 2016
    Assignee: Icera, Inc.
    Inventors: Stephen Allpress, Edward Andrews, Simon Huckett, Laolu Lijofi, Jonathan Peter Lucas, Carlo Luschi, Simon Nicholas Walker
  • Patent number: 9143244
    Abstract: A method of mitigating interference between carrier frequency bands of a carrier aggregation scheme. The method comprises: at a wireless device, receiving a first signal on a first carrier frequency band of the carrier aggregation scheme; mixing a second signal onto a second carrier frequency band of the carrier aggregation scheme and transmitting the second signal from the wireless device; executing code on a processing apparatus of the device to generate a reconstructed interference signal, by mixing an instance of the signal with a frequency location of an interfering harmonic from the second carrier frequency band falling in the first carrier frequency band; and removing the reconstructed interference signal from the first signal.
    Type: Grant
    Filed: December 18, 2012
    Date of Patent: September 22, 2015
    Assignee: Nvidia Corporation
    Inventor: Stephen A. Allpress
  • Patent number: 8868078
    Abstract: A mobile terminal comprising: transceiver apparatus for accessing a wireless network using an earlier and a later generation radio access technology, to establish a voice channel and packet data channel; and an inter radio access technology selector configured to monitor a condition for disabling the earlier generation access, being a condition other than coverage under the earlier generation technology falling below an acceptable lower level. The selector makes inter radio access technology decisions dynamically from the mobile terminal by updating registration with the network to indicate that the earlier generation technology is no longer supported. The selector thereby prevents the mobile terminal being subject to decisions from the network that would otherwise impose transfer to the earlier generation. At least some of the decisions made from the mobile terminal thus disable the earlier generation access whilst in presence of at least the lower level of coverage under the earlier generation.
    Type: Grant
    Filed: December 20, 2012
    Date of Patent: October 21, 2014
    Assignee: Nvidia Corporation
    Inventors: Steve Molloy, Stephen A. Allpress, Mathieu Imbault
  • Publication number: 20130310036
    Abstract: A mobile terminal comprising: transceiver apparatus for accessing a wireless network using an earlier and a later generation radio access technology, to establish a voice channel and packet data channel; and an inter radio access technology selector configured to monitor a condition for disabling the earlier generation access, being a condition other than coverage under the earlier generation technology falling below an acceptable lower level. The selector makes inter radio access technology decisions dynamically from the mobile terminal by updating registration with the network to indicate that the earlier generation technology is no longer supported. The selector thereby prevents the mobile terminal being subject to decisions from the network that would otherwise impose transfer to the earlier generation. At least some of the decisions made from the mobile terminal thus disable the earlier generation access whilst in presence of at least the lower level of coverage under the earlier generation.
    Type: Application
    Filed: December 20, 2012
    Publication date: November 21, 2013
    Applicant: NVIDIA CORPORATION
    Inventors: Steve Molloy, Stephen A. Allpress, Mathieu Imbault
  • Patent number: 8582636
    Abstract: An apparatus and method for implementing an equalizer which combines the benefits of a decision feedback equalizer (DFE) with a maximum-a-posterori (MAP) equalizer (or a maximum likelihood sequence estimator, MLSE) to provide an equalization device with significantly lower complexity than a full-state MAP device, but which still provides improved performance over a conventional DFE. The equalizer architecture includes two DFE-like structures, followed by a MAP equalizer. The first DFE forms tentative symbol decisions. The second DFE is used thereafter to truncate the channel response to a desired memory of L1 symbols, which is less than the total delay spread of L symbols of the channel. The MAP equalizer operates over a channel with memory of L1 symbols (where L1<=L), and therefore the overall complexity of the equalizer is significantly reduced.
    Type: Grant
    Filed: February 2, 2010
    Date of Patent: November 12, 2013
    Assignee: Broadcom Corporation
    Inventors: Stephen Allpress, Quinn Li
  • Publication number: 20130260806
    Abstract: A method of mitigating interference between carrier frequency bands of a carrier aggregation scheme. The method comprises: at a wireless device, receiving a first signal on a first carrier frequency band of the carrier aggregation scheme; mixing a second signal onto a second carrier frequency band of the carrier aggregation scheme and transmitting the second signal from the wireless device; executing code on a processing apparatus of the device to generate a reconstructed interference signal, by mixing an instance of the signal with a frequency location of an interfering harmonic from the second carrier frequency band falling in the first carrier frequency band; and removing the reconstructed interference signal from the first signal.
    Type: Application
    Filed: December 18, 2012
    Publication date: October 3, 2013
    Applicant: NVIDIA CORPORATION
    Inventor: Stephen A. Allpress
  • Publication number: 20120183033
    Abstract: Method, apparatus and computer program product for processing an input signal received over a channel of a wireless network at an apparatus. In one embodiment, an apparatus includes a plurality of receiver processing means, wherein each one of the plurality of receiver processing means is repeatedly selected to perform the processing of the input signal for a respective time interval thereby generating a respective plurality of output signals and, only one of the receiver processing means is selected for said processing at a time. A respective quality measure of each of the plurality of output signals is compared. The selection of the plurality of receiver processing means is controlled in dependence upon the comparison of the quality measures of the output signals, such that the receiver processing means which generates the output signal having the quality measure indicating the highest quality is selected for the longest time interval.
    Type: Application
    Filed: January 12, 2012
    Publication date: July 19, 2012
    Inventors: Stephen Allpress, Edward Andrews, Simon Huckett, Laolu Lijofi, Jonathan Peter Lucas, Carlo Luschi, Simon Nicholas Walker
  • Publication number: 20120183037
    Abstract: An apparatus, method and program for processing a signal received over a wireless channel. The apparatus comprises: a channel searcher configured to determine a profile of the channel in the form of energy values for a plurality of rays at respective channel positions, and an equaliser for equalising the signal based on a variable window of the equaliser. The channel searcher is configured to estimate dispersion of the channel by determining a measure of variance of ray distance from a reference position within the channel profile weighted by ray energy. The equaliser is coupled to the channel searcher and arranged to adapt the window in dependence on the measure of energy-weighted ray distance variance.
    Type: Application
    Filed: January 13, 2012
    Publication date: July 19, 2012
    Inventors: Stephen Allpress, Edward Andrews, Simon Huckett, Laolu Lijofi, Jonathan Peter Lucas, Carlo Luschi, Simon Nicholas Walker
  • Publication number: 20100202507
    Abstract: An apparatus and method for implementing an equalizer which combines the benefits of a decision feedback equalizer (DFE) with a maximum-a-posterori (MAP) equalizer (or a maximum likelihood sequence estimator, MLSE) to provide an equalization device with significantly lower complexity than a full-state MAP device, but which still provides improved performance over a conventional DFE. The equalizer architecture includes two DFE-like structures, followed by a MAP equalizer. The first DFE forms tentative symbol decisions. The second DFE is used thereafter to truncate the channel response to a desired memory of L1 symbols, which is less than the total delay spread of L symbols of the channel. The MAP equalizer operates over a channel with memory of L1 symbols (where L1<=L), and therefore the overall complexity of the equalizer is significantly reduced.
    Type: Application
    Filed: February 2, 2010
    Publication date: August 12, 2010
    Inventors: Stephen Allpress, Quinn Li
  • Patent number: 7656943
    Abstract: An apparatus and method for implementing an equalizer which combines the benefits of a decision feedback equalizer (DFE) with a maximum-a-posterori (MAP) equalizer (or a maximum likelihood sequence estimator, MLSE) to provide an equalization device with significantly lower complexity than a full-state MAP device, but which still provides improved performance over a conventional DFE. The equalizer architecture includes two DFE-like structures, followed by a MAP equalizer. The first DFE forms tentative symbol decisions. The second DFE is used thereafter to truncate the channel response to a desired memory of L1 symbols, which is less than the total delay spread of L symbols of the channel. The MAP equalizer operates over a channel with memory of L1 symbols (where L1<=L), and therefore the overall complexity of the equalizer is significantly reduced.
    Type: Grant
    Filed: March 14, 2006
    Date of Patent: February 2, 2010
    Inventors: Stephen Allpress, Quinn Li
  • Publication number: 20060291593
    Abstract: A decoder for use in a wireless communication device, the decoder comprising a correlator for correlating a received data sequence with a set of codewords such that a correlation value is generated for each correlation, wherein the set of codewords correspond to possible codewords that could be generated from encoding bit sequences having a predetermined number of information bits; a selector for selecting a first correlation value and a second correlation value generated by the correlator and for subtracting the second correlation value from the first correlation value to generate a third value; and a comparator for comparing the third value with a predetermined value to generate a decoding reliability indicator.
    Type: Application
    Filed: June 27, 2005
    Publication date: December 28, 2006
    Inventors: Stephen Allpress, Carlo Luschi
  • Publication number: 20060176949
    Abstract: An apparatus and method for implementing an equalizer which combines the benefits of a decision feedback equalizer (DFE) with a maximum-a-posterori (MAP) equalizer (or a maximum likelihood sequence estimator, MLSE) to provide an equalization device with significantly lower complexity than a full-state MAP device, but which still provides improved performance over a conventional DFE. The equalizer architecture includes two DFE-like structures, followed by a MAP equalizer. The first DFE forms tentative symbol decisions. The second DFE is used thereafter to truncate the channel response to a desired memory of L1 symbols, which is less than the total delay spread of L symbols of the channel. The MAP equalizer operates over a channel with memory of L1 symbols (where L1<=L), and therefore the overall complexity of the equalizer is significantly reduced.
    Type: Application
    Filed: March 14, 2006
    Publication date: August 10, 2006
    Inventors: Stephen Allpress, Quinn Li
  • Patent number: 7012957
    Abstract: An apparatus and method for implementing an equalizer which combines the benefits of a decision feedback equalizer (DFE) with a maximum-a-posterori (MAP) equalizer (or a maximum likelihood sequence estimator, MLSE) to provide an equalization device with significantly lower complexity than a full-state MAP device, but which still provides improved performance over a conventional DFE. The equalizer architecture includes two DFE-like structures, followed by a MAP equalizer. The first DFE forms tentative symbol decisions. The second DFE is used thereafter to truncate the channel response to a desired memory of L1 symbols, which is less than the total delay spread of L symbols of the channel. The MAP equalizer operates over a channel with memory of L1 symbols (where L1<=L), and therefore the overall complexity of the equalizer is significantly reduced.
    Type: Grant
    Filed: August 27, 2001
    Date of Patent: March 14, 2006
    Assignee: Broadcom Corporation
    Inventors: Stephen Allpress, Quinn Li
  • Patent number: 5926455
    Abstract: Polyphase channelizing transmitters convert multiple signal channels into a single stream for transmission and corresponding polyphase channelizing receivers process the received stream to recover signals corresponding to the original signal channels. The filter transfer functions for both the transmitters and receivers are designed to have non-recursive numerators and recursive denominators. Such filters can be realized using non-recursive (e.g., finite impulse response (FIR)) filters and recursive (e.g., infinite impulse response) filters on opposite sides of a Fourier transform. For a given application, polyphase structures of the present invention may require fewer coefficients to implement than conventional (e.g., FIR-based) solutions and will therefore be less complex and less expensive.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: July 20, 1999
    Assignee: Lucent Technologies Inc.
    Inventor: Stephen A. Allpress
  • Patent number: 5694079
    Abstract: In a preferred embodiment, an FM demodulator includes an I and Q sampler for generating data samples of I and Q signals of an FM signal. A signal processor derives samples of a modulating waveform of the FM signal from the I and Q data samples, using a Lagrangian interpolation function of the I and Q data samples. Variables include derivatives of the I and Q signals obtained by differentiation of the Lagrangian function. Preferably, the processor further utilizes a correction factor to correct the modulating waveform samples obtained from the Lagrangian-based interpolation, to thereby derive a modulating waveform exhibiting low signal distortion.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: December 2, 1997
    Assignee: Lucent Technologies Inc.
    Inventors: Stephen A. Allpress, Roy Baxter Blake