Patents by Inventor Joachim S. Hammerschmidt

Joachim S. Hammerschmidt 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: 10171129
    Abstract: Embodiments enable communicating Ultra Wideband (UWB) devices to collaborate by exchanging pulse shape information. The UWB devices use the pulse shape information to improve ranging accuracy. The improved ranging accuracy can be used in complex multipath environments where advanced estimation schemes are used to extract an arriving path for time-of-flight estimation. To determine the pulse shape information to be shared, some embodiments include determining location information of a UWB device and selecting the pulse shape information that satisfies regional aspects. The pulse shape information includes a time-zero index specific to a ranging signal that is used by UWB receivers to establish timestamps time-of-flight calculations. Some embodiments include measuring performance characteristics and selecting different pulse shape information based on the performance characteristics for improved accuracy.
    Type: Grant
    Filed: August 21, 2017
    Date of Patent: January 1, 2019
    Assignee: Apple Inc.
    Inventors: Joachim S. Hammerschmidt, Eren Sasoglu
  • Publication number: 20180097521
    Abstract: A method and apparatus for performing a two-point calibration of a VCO in a PLL is disclosed. The method includes determining a first steady state tuning voltage of the VCO with no modulation voltage applied. Thereafter, an iterative process may be performed wherein a modulation voltage is applied to the VCO (along with the tuning voltage) and a modified divisor is applied to the divider circuit in the feedback loop. During each iteration, after the PLL is settled, the tuning voltage is measured and a difference between the current value and the first value is determined. If the current and first values of the turning voltage are not equal, another iteration may be performed, modifying at least one of the modulation voltage and the divisor, and determining the difference between the current and first values of the tuning voltage.
    Type: Application
    Filed: August 14, 2017
    Publication date: April 5, 2018
    Inventors: Joachim S. Hammerschmidt, Robert G. Lorenz
  • Publication number: 20180091340
    Abstract: Systems and methods for efficient estimation of a most likely sequence are provided. In one embodiment, an electronic device includes most likely receiver circuitry that receives a convolutional encoded signal, generates a linearized representation of the convolutional encoded Gaussian minimum-shift keying signal, resulting in a pseudo-symbol stream, estimates a most likely sequence for the pseudo-symbol stream, and decodes the pseudo-symbol stream based upon the most likely sequence.
    Type: Application
    Filed: September 22, 2017
    Publication date: March 29, 2018
    Inventors: Konstantinos Sarrigeorgidis, Joachim S. Hammerschmidt
  • Publication number: 20180048350
    Abstract: An electronic device that communicates with a second electronic device using adaptive frequency hopping across different spectral bands is described. An integrated circuit in the electronic device includes processing logic that determines an adaptive spectral map that specifies channels across multiple spectral bands. During communication with a second electronic device that includes a second integrated circuit using a communication protocol (such as Bluetooth or Bluetooth Low Energy), the integrated circuit selects channels in the adaptive spectral map, where selection can be based on a predefined frequency-hopping sequence.
    Type: Application
    Filed: August 10, 2017
    Publication date: February 15, 2018
    Inventors: Joachim S. HAMMERSCHMIDT, Robert G. LORENZ, Tad J. DREIER
  • Patent number: 8730930
    Abstract: Polling using B-ACK for occasional back-channel traffic in VoWIFI applications. Within wireless communication systems having a relatively asymmetric channel (e.g., relative more downstream traffic than upstream), certain upstream communications (e.g., acknowledgments (ACKs) and/or block acknowledgments (B-ACKs)) include indication therein (e.g., piggybacked therein) that a given downstream located communication device desires/needs to make upstream communication. In some instances, specificity is also provided therein to indicate the type of information to be transmitted upstream. Such a communication protocol mitigates (or eliminates) contention between upstream and downstream traffic in an environment with significantly more downstream traffic (e.g., such as ongoing downstream traffic that may include streaming video). A coordinating device (e.g.
    Type: Grant
    Filed: July 12, 2011
    Date of Patent: May 20, 2014
    Assignee: Broadcom Corporation
    Inventors: Peyush Agarwal, Joachim S. Hammerschmidt, Yasantha N. Rajakarunanayake, Praveen K. Gopala, George Kondylis
  • Patent number: 8369388
    Abstract: Embodiments of a wireless transceiver are provided. Embodiments can be used in multiple-input-multiple-output (MIMO) wireless transceivers. In an embodiment, radio control signal bundles are provided as direct parallel interconnects between digital signal processing modules and the radio module of the wireless transceiver to enable a precise low-latency control of radio functions. In another embodiment, a separate physical line is provided to control each radio setting of the radio module, thereby enabling simultaneous real-time control of any number of radio settings. In a further embodiment, the various digital and analog components of the wireless transceiver are integrated within a single chip of the same process technology.
    Type: Grant
    Filed: December 21, 2007
    Date of Patent: February 5, 2013
    Assignee: Broadcom Corporation
    Inventors: Joachim S. Hammerschmidt, Arya Reza Behzad, Keith Andrews Carter, Simeon Furrer, Rohit Vijay Gaikwad, Jason Alexander Trachewsky, Amit Bagchi, Rajendra Tushar Moorti, Venkateswara Rao Kodavati
  • Publication number: 20120311173
    Abstract: Dynamic wireless channel selection and protocol control for streaming video utilizing transmission delay/packet loss information and channel utilization statistics. A transmission delay and packet loss monitor generates transmission delay information during the transmission of a video stream to remote wireless device(s) over a first wireless channel by timestamping and monitoring video packet(s) and associated transmission acknowledgement(s). The transmission delay information is compared to a predetermined threshold (e.g., a maximum tolerated delay threshold and/or total packet loss threshold) and, if the threshold is exceeded, a second wireless channel is selected for continued transmission of the video stream. In one mode, channel utilization statistics are likewise examined prior to a channel relocation event.
    Type: Application
    Filed: August 31, 2011
    Publication date: December 6, 2012
    Applicant: BROADCOM CORPORATION
    Inventors: Peyush Agarwal, Yasantha N. Rajakarunanayake, Joachim S. Hammerschmidt
  • Publication number: 20120307814
    Abstract: Polling using B-ACK for occasional back-channel traffic in VoWIFI applications. Within wireless communication systems having a relatively asymmetric channel (e.g., relative more downstream traffic than upstream), certain upstream communications (e.g., acknowledgments (ACKs) and/or block acknowledgments (B-ACKs)) include indication therein (e.g., piggybacked therein) that a given downstream located communication device desires/needs to make upstream communication. In some instances, specificity is also provided therein to indicate the type of information to be transmitted upstream. Such a communication protocol mitigates (or eliminates) contention between upstream and downstream traffic in an environment with significantly more downstream traffic (e.g., such as ongoing downstream traffic that may include streaming video). A coordinating device (e.g.
    Type: Application
    Filed: July 12, 2011
    Publication date: December 6, 2012
    Applicant: BROADCOM CORPORATION
    Inventors: Peyush Agarwal, Joachim S. Hammerschmidt, Yasantha N. Rajakarunanayake, Praveen K. Gopala, George Kondylis
  • Publication number: 20120309321
    Abstract: Synchronized calibration for wireless communication devices. A protocol is presented herein that allows for calibration operation(s) by one or more wireless communication devices to mitigate (or eliminate) the disruption caused to the communication medium thereby. A calibration announcement frame is provided by a wireless communication device intending to perform calibration operation(s), and respective receiving wireless communication devices may adaptively determine whether to perform a calibration operation based thereon. In response to a calibration announcement frame, one or more other wireless communication devices may also perform calibration operation(s) (e.g., in accordance with a group calibration event, simultaneously, etc.) or may perform some operations as to minimize any effects that may be incurred during such a calibration operation(s) (e.g., enter into some robust operational mode, power savings mode, etc.). Such a calibration announcement frame may indicate respective time slots (e.g.
    Type: Application
    Filed: July 12, 2011
    Publication date: December 6, 2012
    Applicant: BROADCOM CORPORATION
    Inventors: Peyush Agarwal, Joachim S. Hammerschmidt, Yasantha N. Rajakarunanayake
  • Publication number: 20120307746
    Abstract: A wireless access device transmits encoded media streams to at least first and second clients over a shared wireless channel. First and second transmission windows are established in a transmission frame interval for transmission of media packets to the first and second clients, respectively. An unused portion of one of the transmission windows is identified using, for example, transmission status information (from the wireless access device) associated with the media packets. The unused portion of the transmission window is adaptively reallocated for use in transmission of media packets associated with the other transmission window. In one mode of operation, the reallocation process may trigger a reversal in the order of the first and second transmission windows in subsequent transmission frame intervals.
    Type: Application
    Filed: September 13, 2011
    Publication date: December 6, 2012
    Applicant: BROADCOM CORPORATION
    Inventors: Joachim S. Hammerschmidt, Peyush Agarwal, Yasantha N. Rajakarunanayake, Praveen K. Gopala, Alexander G. MacInnis
  • Patent number: 8194771
    Abstract: A method and apparatus are disclosed for transmitting symbols in a multiple antenna communication system. The disclosed frame structure comprises a preamble having a plurality of long training symbols that are transmitted on a plurality transmit antennas. At least a portion of the frame is delayed on at least one transmit antenna. The disclosed frame formats of the present invention are backwards compatible to existing single antenna communication systems. The delay amount, D, can be approximately equal to one OFDM time sample period, T. The delayed version can be obtained by introducing a time delay into a signal on the delayed branch(es) or by cyclically shifting at least a portion of each frame on the delayed branch(es). The entire frame or only the preamble portion of each frame can be delayed.
    Type: Grant
    Filed: November 16, 2004
    Date of Patent: June 5, 2012
    Assignee: Agere Systems Inc.
    Inventors: Joachim S. Hammerschmidt, Robert John Kopmeiners, Xiaowen Wang
  • Patent number: 8149971
    Abstract: A wireless receiver detects signals received at two or more antennas, with each antenna coupled to an input receive chain. A switch is employed to couple selected input receive chains to one or more corresponding output receive chains during listening, coarse-detection, and fine-adjustment modes. At least one channel selection filter (CSF) is employed in each output receive chain, and the receiver employs sub-ranging. During idle mode, one antenna's input receive chain is connected to two or more CSFs to detect the packet. When the packet is detected, during a coarse-adjustment mode, the CSFs are reconfigured to couple each antenna's input receive chain to a corresponding output receive chain using low-gain signals. During fine-adjustment mode, the various gains are adjusted to be either high- or low-gain to maintain signals within the dynamic range of the corresponding CSFs.
    Type: Grant
    Filed: August 17, 2011
    Date of Patent: April 3, 2012
    Assignee: Agere Systems Inc.
    Inventors: Joachim S. Hammerschmidt, Danilo Manstretta
  • Patent number: 8145161
    Abstract: An integrated circuit radio transceiver and method therefor is operable to determine an antenna configuration for receive operations. More specifically, the system is operable to determine a receive antenna configuration in a network that includes a number of spatial streams, antenna configuration information, code rate, quadrature modulation type, and transmission protocol modulation scheme, etc. Generally, a selected antenna configuration for transmissions to a remote transceiver is used as an initial antenna configuration for receive operations.
    Type: Grant
    Filed: April 29, 2008
    Date of Patent: March 27, 2012
    Assignee: Broadcom Corporation
    Inventors: Simeon Furrer, Joachim S. Hammerschmidt, Arash Behzad, George Kondylis
  • Publication number: 20110299618
    Abstract: A wireless receiver detects signals received at two or more antennas, with each antenna coupled to an input receive chain. A switch is employed to couple selected input receive chains to one or more corresponding output receive chains during listening, coarse-detection, and fine-adjustment modes. At least one channel selection filter (CSF) is employed in each output receive chain, and the receiver employs sub-ranging. During idle mode, one antenna's input receive chain is connected to two or more CSFs to detect the packet. When the packet is detected, during a coarse-adjustment mode, the CSFs are reconfigured to couple each antenna's input receive chain to a corresponding output receive chain using low-gain signals. During fine-adjustment mode, the various gains are adjusted to be either high- or low-gain to maintain signals within the dynamic range of the corresponding CSFs.
    Type: Application
    Filed: August 17, 2011
    Publication date: December 8, 2011
    Applicant: Agere Systems Inc.
    Inventors: Joachim S. Hammerschmidt, Danilo Manstretta
  • Patent number: 8040843
    Abstract: An integrated circuit radio transceiver and method therefor is operable to determine a transmit scheme according to an ordered manner. More specifically, the system is operable to determine a transmit scheme that defines a signaling configuration that includes number of spatial streams, antenna configuration information, code rate, quadrature modulation type, and transmission protocol modulation scheme, transmitting a packet according to the transmit scheme and collecting packet error rate success and failure information of ongoing data transmissions.
    Type: Grant
    Filed: October 19, 2007
    Date of Patent: October 18, 2011
    Assignee: Broadcom Corporation
    Inventors: Simeon Furrer, Joachim S. Hammerschmidt
  • Patent number: 8031808
    Abstract: A wireless receiver detects signals received at two or more antennas, with each antenna coupled to an input receive chain. A switch is employed to couple selected input receive chains to one or more corresponding output receive chains during listening, coarse-detection, and fine-adjustment modes. At least one channel selection filter (CSF) is employed in each output receive chain, and the receiver employs sub-ranging. During idle mode, one antenna's input receive chain is connected to two or more CSFs to detect the packet. When the packet is detected, during a coarse-adjustment mode, the CSFs are reconfigured to couple each antenna's input receive chain to a corresponding output receive chain using low-gain signals. During fine-adjustment mode, the various gains are adjusted to be either high- or low-gain to maintain signals within the dynamic range of the corresponding CSFs.
    Type: Grant
    Filed: February 11, 2008
    Date of Patent: October 4, 2011
    Assignee: Agere Systems Inc.
    Inventors: Joachim S. Hammerschmidt, Danilo Manstretta
  • Patent number: 8009759
    Abstract: A programmable transmitter generates a frame in a frame format according to one of a plurality of operating modes using a frame structure table storing a respective frame format for each of the operating modes. The transmitter includes a frame structure engine that receives a mode selection signal indicative of a select operating mode, and accesses the frame structure table to determine the frame format of the select operating mode. The frame structure engine produces a control signal to a frame generator to control the generation of a frame in the frame format of the select operating mode.
    Type: Grant
    Filed: December 30, 2008
    Date of Patent: August 30, 2011
    Assignee: Broadcom Corporation
    Inventors: Joachim S. Hammerschmidt, Bruce E. Edwards, Venkat Kodavati, Rajendra Tushar Moorti, Ling Su, Jason A. Trachewsky, Andrew Wagner
  • Patent number: 7895495
    Abstract: A station for a communications network. In one embodiment, the station includes a decoder, a check processor, and a transmitter. The decoder is adapted to decode a received encoded data unit. The check processor is adapted to determine whether the encoded data unit has been correctly received. The transmitter is adapted to initiate, prior to the check processor completing the determination whether the encoded data unit has been correctly received, the transmission of an acknowledgment message comprising a frame having a plurality of different fields of data. The transmitter is adapted to modify the transmission of the acknowledgment message if the check processor determines that the data unit has not been correctly received.
    Type: Grant
    Filed: April 13, 2009
    Date of Patent: February 22, 2011
    Assignee: Agere Systems Inc.
    Inventors: Jan Boer, Wilhelmus Diepstraten, Joachim S. Hammerschmidt, Syed Aon Mujtaba
  • Patent number: 7876847
    Abstract: A method for generating soft bit values for a multi-bit symbol encoded in one or more received signals comprises (a) for a plurality of different combinations of multiple bit values, iteratively generating, for each combination, a metric value based on the one or more received signals. The method further comprises (b) for each iteration, maintaining (i) a global extremum register containing a global extremum of the metric values; (ii) a bit occupancy for the global extremum register; and (iii) a plurality of bit bk registers, one for each bit bk in the symbol. Each bit bk register contains an extremum of the metric values corresponding to combinations of multiple bit values whose bit bk value is opposite the bit bk value of the bit occupancy for the global extremum register. The method further comprises (c) generating, for each bit bk in the symbol, a soft bit value based on a difference between the value in the global extremum register and the value in the corresponding bit bk register.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: January 25, 2011
    Assignee: Agere Systems Inc.
    Inventors: Nils Graef, Joachim S. Hammerschmidt
  • Patent number: 7860174
    Abstract: Methods and systems are provided for estimating the DC offset distortion in a receiver. A fast Fourier transform is applied to at least a portion of a preamble portion of the received signal; an impact of the DC offset distortion on one or more empty subcarriers is determined; individual DC estimates are derived based on each of the determinations; and each of the individual DC estimates are combined to obtain an overall DC estimate.
    Type: Grant
    Filed: May 31, 2005
    Date of Patent: December 28, 2010
    Assignee: Agere Systems Inc.
    Inventors: Joachim S. Hammerschmidt, Xiaowen Wang