Patents by Inventor Chandra Khandavalli

Chandra Khandavalli 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: 9899970
    Abstract: A high-power solid-state RFPA includes an output stage having a power transistor and a current enhanced driver that drives the output stage. The current enhanced driver includes an inductor and first and second transistors arranged in totem-pole-like configuration. When the first transistor is turned on and the second transistor is turned off, the inductor supplies a first charging current to the output stage, to assist in charging the input gate-source capacitor (Cgs) of the power transistor in the output stage. The first transistor further provides a second charging current that supplements the first charging current, thereby enhancing charging of the gate-source capacitor Cgs. Conversely, when the first transistor of the driver is turned off and the second transistor is turned on, the second transistor provides a discharge path through which the gate-source capacitor Cgs can discharge.
    Type: Grant
    Filed: June 18, 2015
    Date of Patent: February 20, 2018
    Assignee: Eridan Communications, Inc.
    Inventor: Chandra Khandavalli
  • Publication number: 20160373063
    Abstract: A high-power solid-state RFPA includes an output stage having a power transistor and a current enhanced driver that drives the output stage. The current enhanced driver includes an inductor and first and second transistors arranged in totem-pole-like configuration. When the first transistor is turned on and the second transistor is turned off, the inductor supplies a first charging current to the output stage, to assist in charging the input gate-source capacitor (Cgs) of the power transistor in the output stage. The first transistor further provides a second charging current that supplements the first charging current, thereby enhancing charging of the gate-source capacitor Cgs. Conversely, when the first transistor of the driver is turned off and the second transistor is turned on, the second transistor provides a discharge path through which the gate-source capacitor Cgs can discharge.
    Type: Application
    Filed: June 18, 2015
    Publication date: December 22, 2016
    Applicant: Eridan Communications, Inc.
    Inventor: Chandra Khandavalli
  • Patent number: 8587378
    Abstract: An analog pre-distortion linearizer having predetermined gain and phase characteristics as a function of input RF signal power is disclosed. The linearizer comprises a core circuit comprising an input terminal configured to receive an input RF signal; an output terminal configured to provide a processed version of that signal; a transistor having a gate, a drain, and a source; and a feedback circuit, presenting an impedance at the frequency of the RF signal, connected to the transistor. The gate is connected to the input terminal and the drain is connected to the output terminal. First and second dc bias voltages applied to the gate and drain respectively cause the transistor to operate at a quiescent bias point in a saturated region of the transistor I-V plane. The quiescent bias point and the impedance are selected such that the linearizer has the predetermined gain and phase characteristics.
    Type: Grant
    Filed: March 11, 2012
    Date of Patent: November 19, 2013
    Inventor: Chandra Khandavalli
  • Publication number: 20130127541
    Abstract: An analog pre-distortion linearizer having predetermined gain and phase characteristics as a function of input RF signal power is disclosed. The linearizer comprises a core circuit comprising an input terminal configured to receive an input RF signal; an output terminal configured to provide a processed version of that signal; a transistor having a gate, a drain, and a source; and a feedback circuit, presenting an impedance at the frequency of the RF signal, connected to the transistor. The gate is connected to the input terminal and the drain is connected to the output terminal. First and second dc bias voltages applied to the gate and drain respectively cause the transistor to operate at a quiescent bias point in a saturated region of the transistor I-V plane. The quiescent bias point and the impedance are selected such that the linearizer has the predetermined gain and phase characteristics.
    Type: Application
    Filed: March 11, 2012
    Publication date: May 23, 2013
    Inventor: Chandra Khandavalli
  • Patent number: 5132641
    Abstract: A power divider/combiner circuit is disclosed for connecting to a single port, 2N+1 multi-cell monolithic transistor chips, each chip composed of an even number of cells. A planar binary tree type transmission line structure is provided having first and second ends for connecting 2.sup.P trtansmission line ports at the first end to the single port at the second end, where N and P are each integers greater than or equal to 1, and an equal number of cells are connected to each of the 2.sup.P transmission line ports The value of P is chosen such that ##EQU1## where R is an integer greater than 1, and C is the sum total of the number of cells in the 2N+1 chips. R cells are connected to each of the 2.sup.P transmission line ports, and some cells from at least one transistor chip are connected to a transmission line port which is different from the port to which other cells from that one chip are connected.
    Type: Grant
    Filed: May 1, 1991
    Date of Patent: July 21, 1992
    Assignee: Fujitsu Limited
    Inventor: Chandra Khandavalli
  • Patent number: 4928078
    Abstract: A branch line coupler is disclosed. The device is comprised of multiple ports and branch lines, every two such lines being connected in a junction point. Each branch line has a width which is narrow at each end and increases in a curvilinear manner toward the middle. By virtue of the width design, the device performs the same functions as a conventional coupler, but for much higher frequencies.
    Type: Grant
    Filed: December 22, 1988
    Date of Patent: May 22, 1990
    Assignee: Avantek, Inc.
    Inventor: Chandra Khandavalli