Patents by Inventor Lizhong Zhu

Lizhong Zhu 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: 7825870
    Abstract: A mobile wireless communications device includes a housing and circuit board carried by the housing and having RF circuitry comprising at least one RF component and plurality of other components mounted on the circuit board. An RF metal shield is secured to the circuit board and surrounds and isolates the at least one RF component and plurality of other components within the RF metal shield. An RF absorber is positioned adjacent an area of the RF component that radiates energy to aid in reducing energy radiated from the RF component into the RF metal shield.
    Type: Grant
    Filed: December 15, 2008
    Date of Patent: November 2, 2010
    Assignee: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, Robert Grant, Liviu George, Perry Jarmuszewski
  • Publication number: 20100210318
    Abstract: A mobile wireless communications device may include a portable device housing, wireless communications circuitry carried by the portable device housing, and a self-contained rechargeable battery pack carried by the portable housing for powering the wireless communications circuitry. The self-contained rechargeable battery pack may include a battery casing, at least one internal battery cell carried within the battery casing, internal battery circuitry carried within the battery casing, and at least one internal filter element carried within the battery casing and coupled to the internal battery circuitry.
    Type: Application
    Filed: February 16, 2009
    Publication date: August 19, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, George Mankaruse
  • Publication number: 20100208848
    Abstract: A communications device, in one aspect as a portable wireless communications device, includes an in-phase modulator and power amplifier that receives a baseband I signal and modulates and amplifies the I signal. A quadrature modulator and power amplifier receives a baseband Q signal and modulates and amplifies the Q signal. A power combiner sums and outputs the I and Q signals. An I demodulator circuit receives a signal fed back from the I power amplifier and demodulates the fed back signal to produce demodulated I signals. A Q demodulator circuit receives a signal fed back from the Q power amplifier and demodulates the fed back signal to produce demodulated Q signals. A processor compares the digital, baseband I and Q signals with a demodulated I and Q signals to compensate for amplitude, frequency and phase modulation errors.
    Type: Application
    Filed: February 19, 2009
    Publication date: August 19, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan, Perry Jarmuszewski, Oleksiy Kravets, Kent Nickerson, Nagula Sangary
  • Publication number: 20100188145
    Abstract: The disclosure relates to a system and method for attenuating harmonics in output signals. In the system, an electronic circuit for reducing leakage of radio frequency signals from a power amplifier of a wireless communication device is provided. The circuit comprises: a printed circuit board ‘PCB’ having the power amplifier mounted on the PCB; a first electrical track in the PCB connecting to a power input terminal of the power amplifier; and a first capacitor connected to the first electrical track and a ground reference in the PCB, the first capacitor reducing transmission of radio frequency signals from the input terminal of the power amplifier.
    Type: Application
    Filed: March 31, 2010
    Publication date: July 29, 2010
    Inventors: Lizhong ZHU, George Mankaruse, Michael Corrigan, Jun Xu, Kent Nickerson
  • Publication number: 20100172527
    Abstract: A hearing aid has improved immunity to RF electromagnetic interference produced from wireless communications devices. A microphone receives audio signals from the environment. Audio circuitry is connected to the microphone and amplifies the audio signals. A speaker is connected to the audio circuitry and directs the audio signals into an ear canal of the user of the hearing aid. The audio connection lines connect the microphone and audio circuitry and the speaker and audio circuitry. A filter is connected into each of the audio connection lines and operative for reducing the RF coupling from a wireless communications device.
    Type: Application
    Filed: March 17, 2010
    Publication date: July 8, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong ZHU, George Mankaruse, Michael Corrigan
  • Patent number: 7724084
    Abstract: The invention relates to a system and method for attenuating harmonics in output signals. In the system, an electronic circuit for reducing harmonics of an output signal from a power amplifier in a transmission circuit for a wireless communication device is provided. The circuit comprises: a printed circuit board (PCB); a power amplifier for generating an output signal; and a circuit implemented on the PCB connected to an output terminal of the power amplifier for the output signal. The circuit comprises a first filtering stage; a delay element; and a harmonic filter. The delay element is located between the harmonic filter and the output terminal and the delay element provides a timing delay in the output signal through at least one 0 ohm-rated component. Also, the harmonic filter is a low pass filter having a frequency cut-off point that attenuates first order harmonics of the output signal.
    Type: Grant
    Filed: January 25, 2007
    Date of Patent: May 25, 2010
    Assignee: Research in Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan, Jun Xu, Kent Nickerson
  • Patent number: 7715578
    Abstract: A hearing aid has improved immunity to RF electromagnetic interference produced from wireless communications devices. A microphone receives audio signals from the environment. Audio circuitry is connected to the microphone and amplifies the audio signals. A speaker is connected to the audio circuitry and directs the audio signals into an ear canal of the user of the hearing aid. The audio connection lines connect the microphone and audio circuitry and the speaker and audio circuitry. A filter is connected into each of the audio connection lines and operative for reducing the RF coupling from a wireless communications device.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: May 11, 2010
    Assignee: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan
  • Publication number: 20100029214
    Abstract: A portable audio device having reduced sensitivity to RF interference over a predetermined frequency range from an adjacent mobile wireless communications device may include a portable housing, a battery carried thereby, a recharging power input connected to the battery, a digital signal input, and an audio analog signal output. A digital-to-analog converter (DAC) may be carried by the portable housing and powered by the battery for converting a selected digital audio file from a memory into an analog audio signal. An audio analog amplifier may be connected between the DAC and the audio analog signal output. A first RF filter(s) may be connected to the recharging power input, and a second RF filter(s) may be connected to the audio analog signal output, both for reducing RF interference over the predetermined frequency range from the adjacent mobile wireless communications device.
    Type: Application
    Filed: October 6, 2009
    Publication date: February 4, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, George Mankaruse
  • Publication number: 20100013718
    Abstract: A mobile wireless communications device includes a housing and at least one circuit board. Radio frequency (RF) circuitry is carried by the circuit board and includes a transceiver. A processor is carried by the at least one circuit board and operative with the RF circuitry. An antenna is mounted within the housing. An antenna contact is secured on the at least one circuit board and operatively connects the RF circuitry and engages the antenna at an antenna contact point. Electromagnetic interference (EMI) shielding is positioned at the antenna contact point and reduces RF inductance effects.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 21, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong ZHU, George Mankaruse, Michael Corrigan, Perry Jarmuszewski, Jun Jun Xu
  • Publication number: 20100016032
    Abstract: A mobile wireless communications device includes a housing an antenna, and radio frequency (RF) circuitry. A transceiver is connected to the antenna and a processor is operative with the RF circuitry. The transceiver includes an In-phase and Quadrature (I/Q) Modulation and Power Amplification circuit having an In-phase (I) circuit with a modulator mixer and power amplifier circuit. A Quadrature (Q) circuit includes a modulator mixer and power amplifier circuit. A power combiner receives the separately amplified In-phase and Quadrature signals and sums and outputs the signals as a combined I and Q signal. The I and Q circuits are isolated from the combined I and Q signal to enhance antenna matching and transmitted radiated power (TRP) and reduce harmonic emission from the power amplification circuits.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 21, 2010
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan, Perry Jarmuszewski
  • Publication number: 20100016033
    Abstract: In accordance with a non-limiting aspect, a mobile wireless communications device includes a housing, at least one circuit board carried by the housing, radio frequency (RF) circuitry, and a processor. An antenna is operative with the RF circuitry. A charging circuit charges a battery carried by and powers the device and includes at least one charging contact carried by the housing and configured for engaging an external charging cradle when connected thereto. It includes an internal connector extending to at least one circuit board and connecting to the charging circuitry. An RF filter includes a ferrite material surrounding at least a portion of the internal connector to minimize RE coupling from the at least one charging contact to the antenna and reduce transmitter harmonics emission and receiver de-sense.
    Type: Application
    Filed: July 15, 2008
    Publication date: January 21, 2010
    Applicant: Research in Motion Limited
    Inventors: George MANKARUSE, Lizhong Zhu, Michael Corrigan
  • Publication number: 20090280757
    Abstract: A mobile wireless communications device includes a housing and antenna supported by the housing. At least one circuit board is carried by the housing and has radio frequency (RF) circuitry operative with the antenna for receiving and transmitting RF signals through the antenna. A power amplifier is connected within a transmission line for amplifying RF signals to be transmitted over the transmission line to the antenna. An antenna switch is carried by the circuit board and connected to the antenna and RF circuitry. An RF shield surrounds the power amplifier and antenna switch isolates the power amplifier and antenna switch from the antenna and RF circuitry.
    Type: Application
    Filed: May 8, 2008
    Publication date: November 12, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan
  • Patent number: 7616973
    Abstract: A portable audio device having reduced sensitivity to RF interference over a predetermined frequency range from an adjacent mobile wireless communications device may include a portable housing, a battery carried thereby, a recharging power input connected to the battery, a digital signal input, and an audio analog signal output. A digital-to-analog converter (DAC) may be carried by the portable housing and powered by the battery for converting a selected digital audio file from a memory into an analog audio signal. An audio analog amplifier may be connected between the DAC and the audio analog signal output. A first RF filter(s) may be connected to the recharging power input, and a second RF filter(s) may be connected to the audio analog signal output, both for reducing RF interference over the predetermined frequency range from the adjacent mobile wireless communications device.
    Type: Grant
    Filed: January 30, 2006
    Date of Patent: November 10, 2009
    Assignee: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, George Mankaruse
  • Publication number: 20090156127
    Abstract: A wireless headset has improved immunity to RF electromagnetic interference produced from wireless communications devices. A headset body is adapted to be worn by a user and includes a microphone and earpiece. An antenna receives wireless communication signals and passes them to RF and audio circuitry mounted within the headset body. The RF and audio circuitry include a Bluetooth module operatively connected to the antenna for transmitting and receiving wireless communication signals, an audio CODEC connected to the Bluetooth module, and audio connection lines connected between the CODEC and the earpiece and between the CODEC and the microphone. A filter is connected into each of the audio connection lines at the earpiece and microphone and operative for reducing the RF coupling from a mobile wireless communications device.
    Type: Application
    Filed: February 18, 2009
    Publication date: June 18, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan
  • Publication number: 20090098917
    Abstract: A mobile wireless communications device and associated method of making same includes a housing and circuit board having a ground plane. Radio frequency (RF) circuitry and a processor are carried by the circuit board and operative with each other. An antenna is carried by the housing and operative with the RF circuitry. Audio circuitry is carried by the circuit board and operative with the RF circuitry and processor. An audio transducer assembly such as a receiver is carried by the circuit board and engages audio circuitry for carrying audio signals between the audio circuitry and speaker. A filter is mounted at the speaker for blocking RF energy from the antenna through the speaker to the ground plane and decoupling the antenna from the speaker and any other components on the circuit board to minimize any detuning of antenna impedance match and degradation in antenna gain.
    Type: Application
    Filed: December 17, 2008
    Publication date: April 16, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong ZHU, Yihong Qi, Michael Corrigan, Krystyna Bandurska, Ying Tong Man
  • Publication number: 20090093286
    Abstract: A mobile wireless communications device includes a housing and circuit board carried by the housing and having RF circuitry comprising at least one RF component and plurality of other components mounted on the circuit board. An RF metal shield is secured to the circuit board and surrounds and isolates the at least one RF component and plurality of other components within the RF metal shield. An RF absorber is positioned adjacent an area of the RF component that radiates energy to aid in reducing energy radiated from the RF component into the RF metal shield.
    Type: Application
    Filed: December 15, 2008
    Publication date: April 9, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, Robert Grant, Liviu George, Perry Jarmuszewski
  • Patent number: 7515944
    Abstract: A wireless headset has improved immunity to RF electromagnetic interference produced from wireless communications devices. A headset body is adapted to be worn by a user and includes a microphone and earpiece. An antenna receives wireless communication signals and passes them to RF and audio circuitry mounted within the headset body. The RF and audio circuitry include a Bluetooth module operatively connected to the antenna for transmitting and receiving wireless communication signals, an audio CODEC connected to the Bluetooth module, and audio connection lines connected between the CODEC and the earpiece and between the CODEC and the microphone. A filter is connected into each of the audio connection lines at the earpiece and microphone and operative for reducing the RF coupling from a mobile wireless communications device.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: April 7, 2009
    Assignee: Research In Motion Limited
    Inventors: Lizhong Zhu, George Mankaruse, Michael Corrigan
  • Publication number: 20090080643
    Abstract: A telephone to be connected to a wireline having reduced sensitivity to RE interference over a predetermined frequency range from an adjacent mobile wireless communications device may include a transmit amplifier, a receive amplifier, an audio input transducer connected to the transmit amplifier, and an audio output transducer connected to the receive amplifier. The telephone may further include an RE shield(s) surrounding the audio input transducer and the audio output transducer for reducing RE interference over the predetermined frequency range from the adjacent mobile wireless communications device. Moreover, the telephone may also include at least one RE audio input filter element connected to the audio input transducer and at least one RE audio output filter element connected to the audio output transducer, both of which are also for reducing RE interference over the predetermined frequency range from the adjacent mobile wireless communications device.
    Type: Application
    Filed: December 2, 2008
    Publication date: March 26, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, George Mankaruse, Perry Jarmuszewski
  • Publication number: 20090033572
    Abstract: A system for testing a communications device includes a portable wireless communications device comprising a transmitter for transmitting an RF signal. A monitoring device receives the RF signals from the portable wireless communications device and analyzes the RF signals to determine total radiated power emitted from the transmitter. An adaptive antenna equivalent circuit is coupled to the transmitter. A connection line extends between the adaptive antenna equivalent circuit and the monitoring device. The adaptive antenna equivalent circuit has an equivalent antenna impedance matched to the portable wireless communications device and the connection line and monitoring device based on transmit frequency to ensure that total radiated power of the RF signals is transmitted from the transmitter to the monitoring device.
    Type: Application
    Filed: August 1, 2007
    Publication date: February 5, 2009
    Applicant: Research In Motion Limited
    Inventors: Lizhong Zhu, Michael Corrigan, Perry Jarmuszewski, Ying Tong Man, George Mankaruse, Yihong Qi
  • Patent number: 7483727
    Abstract: A mobile wireless communications device and associated method of making same includes a housing and circuit board having a ground plane. Radio frequency (RF) circuitry and a processor are carried by the circuit board and operative with each other. An antenna is carried by the housing and operative with the RF circuitry. Audio circuitry is carried by the circuit board and operative with the RF circuitry and processor. An audio transducer assembly such as a receiver is carried by the circuit board and engages audio circuitry for carrying audio signals between the audio circuitry and speaker. A filter is mounted at the speaker for blocking RF energy from the antenna through the speaker to the ground plane and decoupling the antenna from the speaker and any other components on the circuit board to minimize any detuning of antenna impedance match and degradation in antenna gain.
    Type: Grant
    Filed: April 4, 2005
    Date of Patent: January 27, 2009
    Assignee: Research In Motion Limited
    Inventors: Lizhong Zhu, Yihong Qi, Michael Corrigan, Krystyna Bandurska, Ying Tong Man