Patents by Inventor Zhongming Shi

Zhongming Shi 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: 8571149
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Grant
    Filed: June 7, 2010
    Date of Patent: October 29, 2013
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza (Reza) Rofougaran, Arya Reza Behzad
  • Publication number: 20100248670
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Application
    Filed: June 7, 2010
    Publication date: September 30, 2010
    Applicant: BROADCOM CORPORATION
    Inventors: Zhongming Shi, Ahmadreza (Reza) Rofougaran, Arya Reza Behzad
  • Patent number: 7733981
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Grant
    Filed: July 4, 2008
    Date of Patent: June 8, 2010
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza (Reza) Rofougaran, Arya Reza Behzad
  • Publication number: 20080267319
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Application
    Filed: July 4, 2008
    Publication date: October 30, 2008
    Applicant: BROADCOM CORPORATION
    Inventors: ZHONGMING SHI, AHMADREZA (REZA) ROFOUGARAN, ARYA REZA BEHZAD
  • Patent number: 7397868
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Grant
    Filed: May 1, 2007
    Date of Patent: July 8, 2008
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza (Reza) Rofougaran, Arya Reza Behzad
  • Publication number: 20070201565
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Application
    Filed: May 1, 2007
    Publication date: August 30, 2007
    Applicant: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza (Reza) Rofougaran, Arya Behzad
  • Patent number: 7224722
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down-converted to baseband frequencies and baseband signals to be up-converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning a local oscillation frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Grant
    Filed: September 26, 2002
    Date of Patent: May 29, 2007
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza Rofougaran, Arya Reza Behzad
  • Patent number: 7212586
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Grant
    Filed: January 18, 2002
    Date of Patent: May 1, 2007
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Reza Rofougaran, Arya Reza Behzad
  • Patent number: 7158762
    Abstract: A single chip radio transceiver includes circuitry that enables received RF signals to be down-converted to baseband frequencies and baseband signals to be up-converted to RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, received signal strength indicators for adjusting frontal and rear amplification stages accordingly, and, finally, filtering circuitry to filter high and low frequency interfering signals, including DC offset.
    Type: Grant
    Filed: January 10, 2003
    Date of Patent: January 2, 2007
    Assignee: Broadcom Corporation
    Inventors: Zhongming Shi, Ahmadreza Rofougaran, Arya Behzad
  • Patent number: 7020449
    Abstract: A variable gain amplifier includes circuit elements that may be partially powered down during transmit modes of operation and that may be powered back up whenever the radio transceiver receives a data packet within a specified settle time even for high throughput RF communications. The radio transceiver circuit may be powered down even in high throughput communications during a transmit mode to reduce power consumption. A DC offset cancellation block is operably coupled to the variable gain block to substantially remove any DC offset from the amplified output. The variable gain amplifier is further able to provide DC offset cancellation within the required settle time by holding the offset value during a dormant mode of operation.
    Type: Grant
    Filed: October 21, 2002
    Date of Patent: March 28, 2006
    Assignee: Broadcom Corporation
    Inventor: Zhongming Shi
  • Publication number: 20040137852
    Abstract: A single chip radio transceiver includes circuitry that enables received RF signals to be down-converted to baseband frequencies and baseband signals to be up-converted to RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, received signal strength indicators for adjusting frontal and rear amplification stages accordingly, and, finally, filtering circuitry to filter high and low frequency interfering signals, including DC offset.
    Type: Application
    Filed: January 10, 2003
    Publication date: July 15, 2004
    Inventors: Zhongming Shi, Ahmadreza Rofougaran, Arya Behzad
  • Publication number: 20040077326
    Abstract: A variable gain amplifier includes circuit elements that may be partially powered down during transmit modes of operation and that may be powered back up whenever the radio transceiver receives a data packet within a specified settle time even for high throughput RF communications. The radio transceiver circuit may be powered down even in high throughput communications during a transmit mode to reduce power consumption. A DC offset cancellation block is operably coupled to the variable gain block to substantially remove any DC offset from the amplified output. The variable gain amplifier is further able to provide DC offset cancellation within the required settle time by holding the offset value during a dormant mode of operation.
    Type: Application
    Filed: October 21, 2002
    Publication date: April 22, 2004
    Inventor: Zhongming Shi
  • Publication number: 20030138034
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down-converted to baseband frequencies and baseband signals to be up-converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning a local oscillation frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Application
    Filed: September 26, 2002
    Publication date: July 24, 2003
    Inventors: Zhongming Shi, Ahmadreza Rofougaran, Arya Reza Behzad
  • Publication number: 20030138032
    Abstract: A single chip radio transceiver includes circuitry that enables received wideband RF signals to be down converted to base band frequencies and base band signals to be up converted to wideband RF signals prior to transmission without requiring conversion to an intermediate frequency. The circuitry includes a low noise amplifier, automatic frequency control circuitry for aligning the LO frequency with the frequency of the received RF signals, signal power measuring circuitry for measuring the signal to signal and power ratio and for adjusting frontal and rear amplification stages accordingly, and finally, filtering circuitry to filter high and low frequency interfering signals including DC offset.
    Type: Application
    Filed: January 18, 2002
    Publication date: July 24, 2003
    Applicant: Broadcom Corporation
    Inventors: Zhongming Shi, Reza Rofougaran
  • Patent number: 6332083
    Abstract: Apparatus, and an associated method, for the IF stage of a receiver, such as the receive portion of a multi-mode mobile station. Direct conversion of an IF-stage receive signal is made into the digital domain through the use of a &Sgr;&Dgr; analog-to-digital converter. Increased portions of the receiver processes signals in the digital domain using digital-domain circuitry.
    Type: Grant
    Filed: March 30, 1999
    Date of Patent: December 18, 2001
    Assignee: Nokia Mobile Phones Limited
    Inventors: Zhongming Shi, Ken Hsu
  • Patent number: 5821891
    Abstract: A demodulator subsystem incorporates second-order filtering for use within a sigma-delta DAC. A conventional demodulator is modified to include circuitry which manifests a second-order filtering response to the output of the demodulator. The added circuitry includes an additional pair of phased switched capacitor legs and a fixed capacitor. The combination of the additional circuitry with the existing phase switched and fixed capacitors of the conventional demodulator creates an additional pole which provides second order filtering to the demodulator output, effectively eliminating the high-order post filtering and minimizing both the circuit area required for implementation of the demodulator and its power consumption.
    Type: Grant
    Filed: December 26, 1996
    Date of Patent: October 13, 1998
    Assignee: Nokia Mobile Phones, Ltd.
    Inventors: Zhongming Shi, Ken Hsu, Kim Kaltiokallio