Patents Assigned to Electronics and Telecommunications Research Center
  • Publication number: 20020097779
    Abstract: An orthogonal complex spreading method for a multichannel and an apparatus thereof are disclosed. The method includes the steps of complex-summing &agr;n1WM,n1Xn1 which is obtained by multiplying an orthogonal Hadamard sequence WM,n1 by a first data Xn1 of a n-th block and &agr; n2WM,n2Xn2 which is obtained by multiplying an orthogonal Hadamard sequence W1,n2 by a second data Xn2 of a n-th block; complex-multiplying &agr;n1WM,n1Xn1+j&agr;n2WM,n2Xn2 which is summed in the complex type and WM,n3+jPWM,n4 of the complex type using a complex multiplier and outputting as an in-phase information and quadrature phase information; and summing only in-phase information outputted from a plurality of blocks and only quadrature phase information outputted therefrom and spreading the same using a spreading code.
    Type: Application
    Filed: March 27, 2001
    Publication date: July 25, 2002
    Applicant: Electronics and Telecommunications Research Center
    Inventors: Seung Chan Bang, Jae Ryong Shim, Ki Chul Han, Jung Im Kim, Tae Joong Kim
  • Patent number: 5751468
    Abstract: A vertical modulator with a dual mode distributed Bragg reflection (DBR), includes a pair of integrated elements using different wavelengths to provide functions of logical operation, data switching and wavelength conversion. The optical device includes a first optical structure operating at a first wavelength (.lambda..sub.1) and a second optical structure operating at a second wavelength (.lambda..sub.2). The first and second optical structures are formed over a semiconductor substrate. The first optical structure, which operates at the first wavelength (.lambda..sub.1), transmits its data to the second optical structure so that data corresponding to the second wavelength (.lambda..sub.2) can be output. Since the wavelength of input light is different from the wavelength of output light, the optical device serves as a modulator which performs a logic operation and switching function while carrying out wavelength conversion.
    Type: Grant
    Filed: September 20, 1996
    Date of Patent: May 12, 1998
    Assignee: Electronics and Telecommunications Research Center
    Inventors: Kyung-Sook Hyun, O-Kyun Kwon, Kwang-Joon Kim, El-Hang Lee