Patents by Inventor Francis Swarts

Francis Swarts 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: 8432953
    Abstract: A method and an apparatus for efficient Gold code generation and management in WCDMA systems are presented. Aspects of the method may include simultaneously generating, based on the codeword sequence, a plurality of scrambling code segments associated with a scrambling code. A plurality of scrambling code segments, where each is associated with a corresponding one of a plurality of scrambling codes, may also be simultaneously generated. The plurality of scrambling codes may form a scrambling code group. Based on the codeword sequence, a plurality of time shifted versions of at least one scrambling code segment associated with a scrambling code may also be simultaneously generated.
    Type: Grant
    Filed: December 5, 2011
    Date of Patent: April 30, 2013
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Francis Swarts
  • Patent number: 8411729
    Abstract: In a WCDMA network, a communication system may include a baseband processor that enables determination of a primary synchronization position and a plurality of scrambling codes based on received configuration information from at least one base station. The baseband processor may also determine a slot boundary in at least one signal received from the at least one base station based on the determined primary synchronization position. The baseband processor may concurrently apply segments of the plurality of scrambling codes to the received at least one signal. The segments of the plurality of scrambling codes are generated from a plurality of time shifted versions of one of the plurality of scrambling codes. The system may also include a multipath detector that enables unscrambling of the received at least one signal based on the determined slot boundary and at least a portion of the one or more scrambling codes.
    Type: Grant
    Filed: December 2, 2011
    Date of Patent: April 2, 2013
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Francis Swarts, Uri Landau
  • Patent number: 8401123
    Abstract: A mobile device receives a radio frequency (RF) signal comprising a primary synchronization sequence (PSS) and a secondary synchronization sequence (SSS). The mobile device performs multiple frequency hypothesis (MFH) testing via multiple MFH branches. A PSS correlation process is performed for each MFH branch. Frequency offset for receiving data is estimated using resulting correlation data. A desired offset is placed in each MFH branch. A baseband signal is frequency offset per MFH branch according to the desired frequency offset before the PSS correlation process. A received PSS is detected based on a maximum PSS correlation over the entire set of MFH branches. A frequency offset is estimated for the MFH branch associated with the detected PSS by combining an associated residual frequency with a corresponding desired offset. The frequency offset estimate is used for baseband signal processing and/or adjusting a reference oscillator frequency at the mobile device.
    Type: Grant
    Filed: July 28, 2009
    Date of Patent: March 19, 2013
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8380151
    Abstract: Aspects of a method and system for reducing the complexity of multi-frequency hypothesis testing using an iterative approach may include estimating a frequency offset of a received signal via a plurality of iterative frequency offset hypotheses tests. The iterative frequency offset hypotheses may be adjusted for each iteration. A correlation may be done between a primary synchronization signal (PSS), and one or more frequency offset versions of a received signal to control the adjustment of the iterative frequency offset hypotheses. A frequency of the received local oscillator signal may be adjusted based on the estimated frequency offset. One or more frequency offset version of the received signal may be generated via one or more multiplication, and the multiplication may be achieved via a multiplication signal corresponding to one or more frequency offsets. The frequency offset of the received signal may be estimated via the correlation.
    Type: Grant
    Filed: March 11, 2010
    Date of Patent: February 19, 2013
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8369279
    Abstract: A mobile device receives a signal comprising a PSS and a SSS. The mobile device performs iterative MFHT utilizing a reduced number of MFH branches. At each iteration, frequency offset estimation and Cell-ID detection are concurrently performed. An iteration starts with selecting initial frequency offsets spanning a frequency offset estimation range. The selected initial frequency offsets are placed in the MFH branches. A particular MFH branch with a maximum PSS correlation peak magnitude is selected at the iteration. A frequency offset estimate in the selected MFH branch is utilized for frequency control. The frequency offset estimation range utilized for the current iteration is reduced for the next iteration. A Cell-ID is declared if the Cell-ID is consistently detected not only within a particular iteration on the basis of having detected consistent cell ID information for the first and second halves of a radio frame, but also from iteration to iteration.
    Type: Grant
    Filed: March 25, 2010
    Date of Patent: February 5, 2013
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8326251
    Abstract: A mobile device receives a radio frequency (RF) signal, comprising a physical signal such as a primary synchronization signal (PSS), from a serving base station. Two successive samples derived from the received physical signal such as a PSS are selected to generate a single phasor. A receiver frequency offset for the received RF signal is estimated utilizing the generated single phasor. A correlation process is performed to detect the received PSS. An angular increment in the first quadrant is calculated utilizing the generated single phasor. An actual angular increment subject to the receiver frequency offset is calculated based on the angular increment in the first quadrant and signs of real and imaginary components of the generated single phasor. The receiver frequency offset is determined based on the calculated actual angular increment and is utilized to adjust a reference or local oscillator frequency of the mobile device.
    Type: Grant
    Filed: April 23, 2010
    Date of Patent: December 4, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Publication number: 20120281792
    Abstract: A mobile device coupled to a common system clock receives a signal comprising a primary synchronization sequence (PSS) and a secondary synchronization sequence (SSS) in a radio frame. Sample counts are generated for timed events based on corresponding operating bandwidths. The timed events are detected at modulo sample counts of the generated sample counts according to corresponding operating bandwidths. PSS symbol timing determined via the PSS synchronization is aligned to the generated sample counts based on corresponding operating bandwidth. The generated sample counts are bit-shifted relative to the aligned PSS symbol timing for other timed events based on corresponding operating bandwidths. The one or more timed events are determined via performing modulo counting after the bit-shifting. Timing operations are performed at the determined timed events and the determined one or more timed events are refined, accordingly.
    Type: Application
    Filed: May 25, 2012
    Publication date: November 8, 2012
    Applicant: Broadcom Corporation
    Inventors: Francis SWARTS, Mark Kent
  • Publication number: 20120275379
    Abstract: Aspects of a method and system for frame timing acquisition in evolved universal terrestrial radio access (EUTRA) may include determining a received secondary synchronization sequence (SSS) based on a selected cyclic prefix length and on synchronization of a primary synchronization sequence (PSS). A first portion of information associated with the received SSS may be processed separately from a second portion of information associated with the received SSS. A frame timing and/or base station identifier may be determined by comparing the processed first portion of information with the processed second portion of information. The cyclic prefix length may be selected from a finite set of possible cyclic prefix lengths. The cyclic prefix length may be, for example, 9 samples or 32 samples. The primary synchronization sequence synchronization may be determined via correlation.
    Type: Application
    Filed: April 30, 2012
    Publication date: November 1, 2012
    Applicant: Broadcom Corporation
    Inventors: Francis SWARTS, Mark KENT
  • Publication number: 20120243512
    Abstract: Methods and systems for dual frequency timing acquisition for compressed WCDMA communication networks may include processing received WCDMA signals. The WCDMA signals, which may be primary synchronization channel signals, may comprise signals transmitted by one base station at one frequency band and by another base station at a different frequency band, during a compressed frame. Samples of the received WCDMA signals from the different base stations may be stored in portions of a memory allocated for signals from each base station. The received WCDMA signals having the first frequency band may be processed via the processing circuitry during a non-compressed frame. The samples corresponding to the signals with the first frequency band during the non-compressed frame may be stored in the memory. The received WCDMA signals may be sampled at a faster rate during the non-compressed frame than during the compressed frame.
    Type: Application
    Filed: June 5, 2012
    Publication date: September 27, 2012
    Applicant: Broadcom Corporation
    Inventors: Francis SWARTS, Mark Kent, Uri Landau
  • Patent number: 8218517
    Abstract: Methods and systems for dual frequency timing acquisition for compressed WCDMA communication networks may include processing received WCDMA signals. The WCDMA signals, which may be primary synchronization channel signals, may comprise signals transmitted by one base station at one frequency band and by another base station at a different frequency band, during a compressed frame. Samples of the received WCDMA signals from the different base stations may be stored in portions of a memory allocated for signals from each base station. The received WCDMA signals having the first frequency band may be processed via the processing circuitry during a non-compressed frame. The samples corresponding to the signals with the first frequency band during the non-compressed frame may be stored in the memory. The received WCDMA signals may be sampled at a faster rate during the non-compressed frame than during the compressed frame.
    Type: Grant
    Filed: February 28, 2006
    Date of Patent: July 10, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent, Uri Landau
  • Patent number: 8189541
    Abstract: A mobile device coupled to a common system clock receives a signal comprising a primary synchronization sequence (PSS) and a secondary synchronization sequence (SSS) in a radio frame. Sample counts are generated for timed events based on corresponding operating bandwidths. The timed events are detected at modulo sample counts of the generated sample counts according to corresponding operating bandwidths. PSS symbol timing determined via the PSS synchronization is aligned to the generated sample counts based on corresponding operating bandwidth. The generated sample counts are bit-shifted relative to the aligned PSS symbol timing for other timed events based on corresponding operating bandwidths. The one or more timed events are determined via performing modulo counting after the bit-shifting. Timing operations are performed at the determined timed events and the determined one or more timed events are refined, accordingly.
    Type: Grant
    Filed: July 13, 2009
    Date of Patent: May 29, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8170592
    Abstract: Aspects of a method and system for frame timing acquisition in evolved universal terrestrial radio access (EUTRA) may include determining a received secondary synchronization sequence (SSS) based on a selected cyclic prefix length and on synchronization of a primary synchronization sequence (PSS). A first portion of information associated with the received SSS may be processed separately from a second portion of information associated with the received SSS. A frame timing and/or base station identifier may be determined by comparing the processed first portion of information with the processed second portion of information. The cyclic prefix length may be selected from a finite set of possible cyclic prefix lengths. The cyclic prefix length may be, for example, 9 samples or 32 samples. The primary synchronization sequence synchronization may be determined via correlation.
    Type: Grant
    Filed: October 15, 2008
    Date of Patent: May 1, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Publication number: 20120076175
    Abstract: A method and an apparatus for efficient Gold code generation and management in WCDMA systems are presented. Aspects of the method may include simultaneously generating, based on the codeword sequence, a plurality of scrambling code segments associated with a scrambling code. A plurality of scrambling code segments, where each is associated with a corresponding one of a plurality of scrambling codes, may also be simultaneously generated. The plurality of scrambling codes may form a scrambling code group. Based on the codeword sequence, a plurality of time shifted versions of at least one scrambling code segment associated with a scrambling code may also be simultaneously generated.
    Type: Application
    Filed: December 5, 2011
    Publication date: March 29, 2012
    Inventors: Mark Kent, Francis Swarts
  • Publication number: 20120069923
    Abstract: In a WCDMA network, a communication system may include a baseband processor that enables determination of a primary synchronization position and a plurality of scrambling codes based on received configuration information from at least one base station. The baseband processor may also determine a slot boundary in at least one signal received from the at least one base station based on the determined primary synchronization position. The baseband processor may concurrently apply segments of the plurality of scrambling codes to the received at least one signal. The segments of the plurality of scrambling codes are generated from a plurality of time shifted versions of one of the plurality of scrambling codes. The system may also include a multipath detector that enables unscrambling of the received at least one signal based on the determined slot boundary and at least a portion of the one or more scrambling codes.
    Type: Application
    Filed: December 2, 2011
    Publication date: March 22, 2012
    Inventors: Mark Kent, Francis Swarts, Uri Landau
  • Patent number: 8135096
    Abstract: Aspects of a method and system for the extension of frequency offset estimation range based on correlation of complex sequences may include partitioning each of a received sample sequence and a local replica sample sequence into three or more similar length contiguous sample sub-sequences. For each of the three or more similar length contiguous sample sub-sequences, a correlation coefficient may be determined between corresponding sample sub-sequences of the partitioned received sample sequence and the local replica sample sequence. A plurality of phase differences may be determined based on adjacent ones of the determined correlation coefficients, and the determined plurality of phase differences may be averaged to generate a phase increment estimate. The communication system may be compliant with a wireless standard, comprising UMTS EUTRA (LTE), WiMAX (IEEE 802.16), and/or WLAN (IEEE 802.11).
    Type: Grant
    Filed: October 15, 2008
    Date of Patent: March 13, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8126948
    Abstract: Aspects of a method and system for constant amplitude random sequence construction may include generating one or more real signal components via a random number generator, wherein each of the generated one or more real signal components may be subjected to an amplitude constraint. One or more corresponding imaginary signal components may be generated, each of which may be derived from a relationship between the generated one or more real signal components and the amplitude constraint. At least the generated one or more real signal components and the generated one or more corresponding imaginary signal components may be combined to generate a complex constant amplitude signal. The one or more real signal components may be generated according to a probability distribution in the random number generator.
    Type: Grant
    Filed: December 27, 2007
    Date of Patent: February 28, 2012
    Assignee: Broadcom Corporation
    Inventors: Francis Swarts, Mark Kent
  • Patent number: 8102900
    Abstract: A method and an apparatus for efficient Gold code generation and management in WCDMA systems are presented. Aspects of the method may include simultaneously generating, based on the codeword sequence, a plurality of scrambling code segments associated with a scrambling code. A plurality of scrambling code segments, where each is associated with a corresponding one of a plurality of scrambling codes, may also be simultaneously generated. The plurality of scrambling codes may form a scrambling code group. Based on the codeword sequence, a plurality of time shifted versions of at least one scrambling code segment associated with a scrambling code may also be simultaneously generated.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: January 24, 2012
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Francis Swarts
  • Patent number: 8077759
    Abstract: A method and an apparatus for new cell identification in a WCDMA network with a given neighbor set are described. Aspects of a system for new cell identification in a WCDMA network with a given neighbor set may include a baseband processor that enables determination of a primary synchronization position and at least one scrambling code based on received configuration information from one or more base stations. The baseband processor may also enable determination of a slot boundary in at least one signal received from the one or more base stations based on the determined primary synchronization position. The system may also include a multipath detector that enables unscrambling of the received at least one signal based on the determined slot boundary and at least a portion of the one or more scrambling codes.
    Type: Grant
    Filed: April 7, 2006
    Date of Patent: December 13, 2011
    Assignee: Broadcom Corporation
    Inventors: Mark Kent, Francis Swarts, Uri Landau
  • Publication number: 20110243105
    Abstract: A mobile device accumulates energy associated with each of successive PSS transmissions received from a base station. Accumulated energy values may be rescaled by a same number of bits whenever a buffer overflow condition occurs within the accumulation buffer. The mobile device may detect a correct PSS timing hypothesis utilizing the rescaled accumulated energy values within the accumulation buffer. A significant bit such as, for example, the most significant bit (MSB) or one of lesser significant bits, of each of the accumulated energy values may be monitored during the energy accumulation process to detect a buffer overflow condition. The mobile device may determine number of bits for rescaling or right shift each of the accumulated energy values in response to the detected buffer overflow condition. The resulting shifted accumulated energy values may be utilized for PSS detection. Either an integrating or filtering method is utilized during the energy accumulation process.
    Type: Application
    Filed: April 27, 2010
    Publication date: October 6, 2011
    Inventors: Francis Swarts, Mark Kent
  • Publication number: 20110243104
    Abstract: A mobile device receives a signal comprising a PSS and performs multiple frequency hypothesis testing (MFHT) on the received signal. The mobile device starts MFHT by applying different initial frequency offsets in corresponding MFH branches. Timing drift in MFHT is compensated based on corresponding initial frequency offsets. In this regard, a PSS correlation process is performed on the received signal in each MFH branch. Resulting PSS correlation data is buffered and processed in corresponding PSS timing hypothesis buffers. The timing position of samples is updated in the PSS timing hypothesis buffers based on corresponding initial frequency offsets. Energy associated with the PSS transmissions may be accumulated utilizing corresponding PSS correlation data at updated sampling positions. The received PSS is detected based on a maximum accumulated energy associated with the PSS transmissions. Information that comes from the detected PSS is utilized by the mobile device to camp on a corresponding cell.
    Type: Application
    Filed: April 27, 2010
    Publication date: October 6, 2011
    Inventors: Francis Swarts, Mark Kent