Patents by Inventor Charles Xiaoping Mao

Charles Xiaoping Mao 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: 6441952
    Abstract: The present invention provides a hybrid Raman/EDFA optical amplifier that utilizes a first optical detector that generates a first electrical or electronic signal that is proportional the combined optical power of the signal light and the leaked pump laser light, a second optical detector that generates a second electrical or electronic signal that is proportional to the power of the pump laser light and an electronic subtraction circuit that receives the first and second electrical or electronic signals and generates a difference signal that is proportional to only to the optical power of the signal light and insensitive to the power of the Raman pump laser light. The difference signal is utilized by an EDFA control circuit to control and/or adjust the operation of the EDFA based upon changes in the power of the input optical signal.
    Type: Grant
    Filed: July 3, 2001
    Date of Patent: August 27, 2002
    Assignee: Avanex Corporation
    Inventors: Xiaodong Duan, Guohua Xiao, Lintao Zhang, Dongqi Liu, Gang Li, Paul Hull, Charles Xiaoping Mao, Simon Xiaofan Cao