Patents by Inventor Rizwan Murji

Rizwan Murji 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).

  • Publication number: 20150003566
    Abstract: A transmitter power supply modulates an RF signal without needing to run a calibration/training cycle every time an exciter or PA module is switched in and out or every time the transmitter powers up. During calibration of the exciter module, an exciter module delay factor is determined, and stored in the exciter module, for each signal modulation scheme that may be implemented by the exciter module. During calibration of a power amplifier (PA) module, a power supply modulation (PSM) delay factor is determined for, and stored in, the PA module. During transmitter operation, the exciter module generates RF and envelope signals based on an input signal. The PA module generates a power supply voltage based on the envelope signal and a final delay factor, which final delay factor is based on the exciter module and PSM delay factors. The PA module then modulates the RF signal using the power supply voltage.
    Type: Application
    Filed: June 26, 2013
    Publication date: January 1, 2015
    Inventor: Rizwan Murji
  • Patent number: 8909180
    Abstract: A transmitter power supply modulates an RF signal without needing to run a calibration/training cycle every time an exciter or PA module is switched in and out or every time the transmitter powers up. During calibration of the exciter module, an exciter module delay factor is determined, and stored in the exciter module, for each signal modulation scheme that may be implemented by the exciter module. During calibration of a power amplifier (PA) module, a power supply modulation (PSM) delay factor is determined for, and stored in, the PA module. During transmitter operation, the exciter module generates RF and envelope signals based on an input signal. The PA module generates a power supply voltage based on the envelope signal and a final delay factor, which final delay factor is based on the exciter module and PSM delay factors. The PA module then modulates the RF signal using the power supply voltage.
    Type: Grant
    Filed: June 26, 2013
    Date of Patent: December 9, 2014
    Assignee: Motorola Solutions, Inc.
    Inventor: Rizwan Murji
  • Patent number: 8483633
    Abstract: A communication device is presented that has different processors and a power amplifier. One of the processors receives a signal from a monitor and indicates that an alarm exists to a diagnostics module. The other processor uses the envelope signal of the input signal to be amplified and either the signal from the diagnostics module, the monitor or the power amplifier to adjust modulation of the power supply of the power amplifier dependent on the type of alarm. The power supply voltage or headroom is maximized or frozen at the value of the last detection cycle if a fault or impairment, respectively, of the power amplifier is detected.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: July 9, 2013
    Assignee: Motorola Solutions, Inc.
    Inventor: Rizwan Murji
  • Patent number: 8417199
    Abstract: A radio is presented that has a processor, memory, modulator and a power amplifier. An envelope of a signal to be transmitted is used by the processor to control modulation of the voltage of the power amplifier by the modulator between a desired minimum voltage and a desired maximum voltage. Using the memory, the desired minimum voltage is determined from the desired maximum voltage and these voltages are less than nominal minimum and maximum voltage, respectively. The desired minimum voltage is tailored for the radio and takes into account environmental conditions to optimize operating conditions for the radio. If the range of voltages would exceed the dynamic range of the radio, the modulation provided by the modulator is controlled by the processor in steps until the desired minimum and maximum voltages are achieved.
    Type: Grant
    Filed: July 23, 2010
    Date of Patent: April 9, 2013
    Assignee: Motorola Solutions, Inc.
    Inventor: Rizwan Murji
  • Publication number: 20120021695
    Abstract: A radio is presented that has a processor, memory, modulator and a power amplifier. An envelope of a signal to be transmitted is used by the processor to control modulation of the voltage of the power amplifier by the modulator between a desired minimum voltage and a desired maximum voltage. Using the memory, the desired minimum voltage is determined from the desired maximum voltage and these voltages are less than nominal minimum and maximum voltage, respectively. The desired minimum voltage is tailored for the radio and takes into account environmental conditions to optimize operating conditions for the radio. If the range of voltages would exceed the dynamic range of the radio, the modulation provided by the modulator is controlled by the processor in steps until the desired minimum and maximum voltages are achieved.
    Type: Application
    Filed: July 23, 2010
    Publication date: January 26, 2012
    Applicant: MOTOROLA, INC.
    Inventor: RIZWAN MURJI
  • Publication number: 20120021708
    Abstract: A communication device is presented that has different processors and a power amplifier. One of the processors receives a signal from a monitor and indicates that an alarm exists to a diagnostics module. The other processor uses the envelope signal of the input signal to be amplified and either the signal from the diagnostics module, the monitor or the power amplifier to adjust modulation of the power supply of the power amplifier dependent on the type of alarm. The power supply voltage or headroom is maximized or frozen at the value of the last detection cycle if a fault or impairment, respectively, of the power amplifier is detected.
    Type: Application
    Filed: July 23, 2010
    Publication date: January 26, 2012
    Applicant: MOTOROLA, INC.
    Inventor: RIZWAN MURJI
  • Patent number: 7760027
    Abstract: An apparatus and method are provided for reducing the output voltage in a power amplifier. The power amplifier contains a power supply, an amplifier stage, an impedance matching circuit, and a voltage reduction unit connected between the power supply and the amplifier stage. A power amplifier device within the amplifier stage has a gain bandwidth that covers multiple frequency bands. The output voltage of the power amplifier device is a composite voltage that contains fundamental and harmonic components that lie within the gain bandwidth. The voltage reduction unit reduces the supply voltage of the power amplifier device such that the composite output voltage is less than the breakdown voltage in the power amplifier device. The impedance matching circuit is coupled to the power amplifier device output and provides impedance matching for output signals of the fundamental and harmonic frequencies.
    Type: Grant
    Filed: May 8, 2008
    Date of Patent: July 20, 2010
    Assignee: Motorola, Inc.
    Inventors: Rizwan Murji, Mitchell R. Blozinski, Rodney W. Hagen
  • Publication number: 20090278610
    Abstract: An apparatus and method are provided for reducing the output voltage in a power amplifier. The power amplifier contains a power supply, an amplifier stage, an impedance matching circuit, and a voltage reduction unit connected between the power supply and the amplifier stage. A power amplifier device within the amplifier stage has a gain bandwidth that covers multiple frequency bands. The output voltage of the power amplifier device is a composite voltage that contains fundamental and harmonic components that lie within the gain bandwidth. The voltage reduction unit reduces the supply voltage of the power amplifier device such that the composite output voltage is less than the breakdown voltage in the power amplifier device. The impedance matching circuit is coupled to the power amplifier device output and provides impedance matching for output signals of the fundamental and harmonic frequencies.
    Type: Application
    Filed: May 8, 2008
    Publication date: November 12, 2009
    Applicant: MOTOROLA, INC.
    Inventors: RIZWAN MURJI, MITCHELL R. BLOZINSKI, RODNEY W. HAGEN