Pulse Or Interrupted Continuous Wave Modulator Patents (Class 332/106)
  • Patent number: 5038051
    Abstract: A switching modulator for a microwave radar transmitter is presented. In embodiment, a string of series connected transistors is controlled from an external source for pulse modulating the cathodes of transmitter microwave tubes. The individual components of the series string can be individually switched ON or OFF in order to maintain regulation of the modulation pulse. In a second embodiment, a pulse transformer has a plurality of individual primary windings and a single secondary winding wherein the primary windings are specially wound to provide isolation between the primary windings with the flux in the secondary winding and the voltage generated in the secondary winding being proportional to the sum of the excitation of the primary windings. Each of the primary windings are individually switchable for regulating the generated output voltage at the secondary winding.
    Type: Grant
    Filed: May 8, 1984
    Date of Patent: August 6, 1991
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Jeffrey C. Firman, Richard E. Rouse, William H. Zinger
  • Patent number: 4896156
    Abstract: A differential delta-sigma modulator of switched-capacitance type is operated with a three-phase cycle, rather than the two-phase cycle of the prior art. In the first phase of operation the switched capacitors are charged in accordance with the previous single-bit output of the modulator. Structural modifications permit the switching capacitors to be connected in series to receive the modulator input voltage during the second phase of operation so that voltage need not be balanced with regard to any specified common-mode potential. In the third phase of operation the switched capacitors discharge from first plates thereof to the differential-input integrator while the second plates thereof are driven in accordance with the previous single-bit output of the modulator.
    Type: Grant
    Filed: October 3, 1988
    Date of Patent: January 23, 1990
    Assignee: General Electric Company
    Inventor: Steven L. Garverick
  • Patent number: 4866737
    Abstract: ASCII characters are coded in the form of 8, 16 or longer digital words. Signal pulses with durations proportional to such digital words are generated and filtered so that the filtered signal has substantially the same duration as the unfiltered signal. The filtered signal fits within the voiceband so that it can be transmitted through a voiceband medium such as a telephone network. At the receiver, zero-crossings of the received signal are detected and from the duration between consecutive zero-crossings, the particular ASCII represented by the duration of such signal may be recovered.
    Type: Grant
    Filed: July 21, 1987
    Date of Patent: September 12, 1989
    Inventor: Bruce Seifried