Patents by Inventor Michael E. Spencer

Michael E. Spencer 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: 7729498
    Abstract: A parametric loudspeaker system using improved modulators to compensate for the non-linearity of the parametric process in air when driving the air at saturation levels and below saturation levels. The parametric loudspeaker uses a pre-processed single sideband modulator that offers ideal linearity as characterized by square root pre-processed double sideband modulators but with a lower carrier frequency and without the wide bandwidth requirements. By eliminating some or all of the lower sideband the carrier frequency can be reduced without producing sideband frequencies in the audible range. Lower operational frequencies result in greater translation efficiency and greater output capability before reaching the saturation limit of air. A pre-processor minimizes the effects of saturation limits for double sideband, truncated double sideband or single sideband processing to achieve superior output.
    Type: Grant
    Filed: January 9, 2007
    Date of Patent: June 1, 2010
    Assignee: American Technology Corporation
    Inventors: Michael E. Spencer, James J. Croft, III, Joseph O. Norris
  • Publication number: 20080013753
    Abstract: Systems and methods for altering audio for more effective delivery to long range targets. An example of the present invention includes a speaker coupled to a processor and one or more sensors suitable for sensing environmental conditions such as temperature and humidity. The processor reads the output of the sensors and compensates for frequency dependent attenuation likely to occur at the sensed environmental condition. In one embodiment, the user specifies a range that the sound is to travel and an equalization table compensating for attenuation at the desired range is selected according to the user input.
    Type: Application
    Filed: July 10, 2007
    Publication date: January 17, 2008
    Applicant: CONQUEST INNOVATIONS, LLC
    Inventors: Terry J. Conrad, Michael E. Spencer
  • Patent number: 7224808
    Abstract: A system configured to dynamically adjust the ultrasonic carrier level in a parametric array system in response to changing source signal input levels, and which employs a look-ahead delay strategy to enable optimal modulation of the carrier wave to eliminate constant ultrasonic carrier emission and reduce the ultrasonic carrier emission to what is actually needed to accommodate the db range of the source material, and at the same time, to also minimize noticeable distortion and sound artifacts of a high-power ultrasonic carrier, and/or distortion/artifacts arising from modulation of an ultrasonic carrier to reduce average power output; and thus it realizes advantages of carrier modulation based on source-signal level, while minimizing inherent drawbacks of carrier modulation.
    Type: Grant
    Filed: September 3, 2002
    Date of Patent: May 29, 2007
    Assignee: American Technology Corporation
    Inventors: Michael E. Spencer, James J. Croft, III
  • Patent number: 7224219
    Abstract: A method and device for frequency shifting and amplifying an audio signal for use in a parametric loudspeaker system is disclosed. The method includes the operation of receiving an input audio signal and creating a reference signal. The audio signal is compared with the reference signal to derive a compared product signal. The compared product signal is sent to a switching power stage. Nonlinear preprocessing is performed with respect to the input audio signal, and/or a non-triangle wave is created as the reference signal. The input audio signal is shifted and amplified by modulating the reference signal in the switching power stage.
    Type: Grant
    Filed: September 18, 2006
    Date of Patent: May 29, 2007
    Assignee: American Technology Corporation
    Inventor: Michael E Spencer
  • Patent number: 7162042
    Abstract: A parametric loudspeaker system using improved modulators to compensate for the non-linearity of the parametric process in air when driving the air at saturation levels and below saturation levels. The parametric loudspeaker uses a pre-processed single sideband modulator that offers ideal linearity as characterized by square root pre-processed double sideband modulators but with a lower carrier frequency and without the wide bandwidth requirements. By eliminating some or all of the lower sideband the carrier frequency can be reduced without producing sideband frequencies in the audible range. Lower operational frequencies result in greater translation efficiency and greater output capability before reaching the saturation limit of air. A pre-processor minimizes the effects of saturation limits for double sideband, truncated double sideband or single sideband processing to achieve superior output.
    Type: Grant
    Filed: March 21, 2003
    Date of Patent: January 9, 2007
    Assignee: American Technology Corporation
    Inventors: Michael E. Spencer, James J. Croft, III, Joseph O. Norris
  • Patent number: 7109789
    Abstract: A modulator-amplifier configured for use in parametric sound reproduction systems, including an input configured for receiving at least one input signal, a reference signal generator configured for generating a reference signal, and a comparator stage coupled to the input and the reference signal generator, the comparator stage configured for detecting relationships between a first signal based on the input signal and the reference signal. A switching power stage coupled to the comparator is configured to receive a second signal derived from a combination of an output from the comparators and the input signal, wherein there is a non-linear relationship between the input signal and the timing of state transitions in the switching power stage for the purpose of generating an output that has been shifted in frequency relative to a frequency of the input signal, and which includes at least one sideband.
    Type: Grant
    Filed: January 21, 2003
    Date of Patent: September 19, 2006
    Assignee: American Technology Corporation
    Inventor: Michael E. Spencer
  • Publication number: 20030185405
    Abstract: A parametric loudspeaker system using improved modulators to compensate for the non-linearity of the parametric process in air when driving the air at saturation levels and below saturation levels. The parametric loudspeaker uses a pre-processed single sideband modulator that offers ideal linearity as characterized by square root pre-processed double sideband modulators but with a lower carrier frequency and without the wide bandwidth requirements. By eliminating some or all of the lower sideband the carrier frequency can be reduced without producing sideband frequencies in the audible range. Lower operational frequencies result in greater translation efficiency and greater output capability before reaching the saturation limit of air. A pre-processor minimizes the effects of saturation limits for double sideband, truncated double sideband or single sideband processing to achieve superior output.
    Type: Application
    Filed: March 21, 2003
    Publication date: October 2, 2003
    Inventors: Michael E. Spencer, James J. Croft, Joseph O. Norris
  • Patent number: 6584205
    Abstract: A parametric loudspeaker system using improved modulators to compensate for the non-linearity of the parametric process in air when driving the air at saturation levels and below saturation levels. The parametric loudspeaker uses a pre-processed single sideband modulator that offers ideal linearity as characterized by square root pre-processed double sideband modulators but with a lower carrier frequency and without the wide bandwidth requirements. By eliminating some or all of the lower sideband the carrier frequency can be reduced without producing sideband frequencies in the audible range. Lower operational frequencies result in greater translation efficiency and greater output capability before reaching the saturation limit of air. A pre-processor minimizes the effects of saturation limits for double sideband, truncated double sideband or single sideband processing to achieve superior output.
    Type: Grant
    Filed: August 26, 1999
    Date of Patent: June 24, 2003
    Assignee: American Technology Corporation
    Inventors: James J. Croft, III, Michael E. Spencer, Joseph O. Norris
  • Publication number: 20030091203
    Abstract: A system configured to dynamically adjust the ultrasonic carrier level in a parametric array system in response to changing source signal input levels, and which employs a look-ahead delay strategy to enable optimal modulation of the carrier wave to eliminate constant ultrasonic carrier emission and reduce the ultrasonic carrier emission to what is actually needed to accommodate the db range of the source material, and at the same time, to also minimize noticeable distortion and sound artifacts of a high-power ultrasonic carrier, and/or distortion/artifacts arising from modulation of an ultrasonic carrier to reduce average power output; and thus it realizes advantages of carrier modulation based on source-signal level, while minimizing inherent drawbacks of carrier modulation.
    Type: Application
    Filed: August 30, 2002
    Publication date: May 15, 2003
    Applicant: American Technology Corporation
    Inventors: James J. Croft, Michael E. Spencer
  • Publication number: 20030091196
    Abstract: A system configured to dynamically adjust the ultrasonic carrier level in a parametric array system in response to changing source signal input levels, and which employs a look-ahead delay strategy to enable optimal modulation of the carrier wave to eliminate constant ultrasonic carrier emission and reduce the ultrasonic carrier emission to what is actually needed to accommodate the db range of the source material, and at the same time, to also minimize noticeable distortion and sound artifacts of a high-power ultrasonic carrier, and/or distortion/artifacts arising from modulation of an ultrasonic carrier to reduce average power output; and thus it realizes advantages of carrier modulation based on source-signal level, while minimizing inherent drawbacks of carrier modulation.
    Type: Application
    Filed: September 3, 2002
    Publication date: May 15, 2003
    Applicant: American Technology Corporation
    Inventors: Michael E. Spencer, James J. Croft