Patents by Inventor Hefeng Wang

Hefeng Wang 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: 5771442
    Abstract: In a dual mode transmitter for modulating, in a digital mode, an input digital signal and transmitting a modulated digital signal and modulating, in an analog mode, an input analog signal and transmitting a modulated analog signal, a digital modulating section modulates the input digital signal to thereby generate the modulated digital signal, and outputs the modulated digital signal. An analog modulator/carrier generator modulates the input analog signal to thereby generate the modulated analog signal, and outputs it. Also, the analog modulator/carrier generator generates a carrier signal for up-converting the modulated digital signal. The up-converter up-converts, in the digital mode, the modulated digital signal by using the carrier signal and receives, in the analog mode, the modulated analog signal and passes it therethrough.
    Type: Grant
    Filed: November 13, 1995
    Date of Patent: June 23, 1998
    Assignee: OKI Electric Industry Co., Ltd.
    Inventors: Hefeng Wang, Tetsuo Onodera
  • Patent number: 5606285
    Abstract: A power control circuit having a saturation preventing control loop including a variable gain amplifier, an RF power amplifier, a directional coupler, a detecting circuit, a comparator, a switch, and an adder. When the signal level of an output signal of the comparator is low, the switch is turned on. When the signal level of the output signal of the comparator is high, the switch is turned off. A system power control loop includes a system power control terminal, the adder, and the variable gain amplifier. Since the saturation preventing control loop is provided with the switch, the saturation preventing control loop operates only when the signal level of the amplified signal is larger than a reference value. The system power control loop can properly operate according to a system power control signal supplied from the system power control terminal.
    Type: Grant
    Filed: July 21, 1995
    Date of Patent: February 25, 1997
    Assignee: OKI Electric Industry Co., Ltd.
    Inventors: Hefeng Wang, Tetsuo Onodera
  • Patent number: 5093839
    Abstract: A frequency diversity receiving system is based on cancellation of a C/A (Clear/Acquisition) code in a GPS (Global Positioning System). Spread spectrum signals of a P code (Precision) code is picked up by removing, in an interference removal circuit, spread spectrum signals of the C/A code out of spread spectrum signals of L.sub.1 band which are transmitted from GPS satellites. A difference in relative delay times between the spread spectrum signals of the P code in L.sub.1 band and spread spectrum signals of the P code in L.sub.2 band, which are also transmitted from GPS satellites, is obtained in a modified DLL (Delay Locked Loop).
    Type: Grant
    Filed: January 2, 1991
    Date of Patent: March 3, 1992
    Assignee: Sokkisha Co., Ltd.
    Inventors: Ryuji Kohno, Hefeng Wang, Hideki Imai