Title:
DIRECT SEQUENCE BAND DIFFUSION CODE CHIP MODULATION DEVICE
Document Type and Number:
Japanese Patent JP3390771
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To obtain a small transmission signal envelope change and a phase change by generating first and second binary codes, making a pseudo noise(PN) binary code into a third binary code, generating a diffusion symbol, generating a quadrature phase sequence, generating an in phase signal and converting the waveform of the quadrature phase sequence into an analog signal.
SOLUTION: A coherent direct sequence band diffusion Walsh QPSK chip modulation device contains the two signal generators of a pilot signal generator 252 and a data signal generator 254. The pilot signal generator 252 and the data signal generator 254 generate the common-mode and quadrature phase analog signals by the method of non-coherent direct sequence band diffusion Walsh QPSK. The input of the pilot signal generator 252 is a PN code generated by a PN code generator 202. The gains of the data signals, which are adjusted by gain adjusting parts 228 and 230, are adjusted in such a way that the power of the pilot signals is reduced.
Inventors:
Lee Dong Wook
Hen Lee
Kim Myung Chin
Hen Lee
Kim Myung Chin
Application Number:
JP23337197A
Publication Date:
March 31, 2003
Filing Date:
August 14, 1997
Export Citation:
Assignee:
Electronics and Telecommunications Research Institute
Dacom Co., Ltd.
Dacom Co., Ltd.
International Classes:
H04L27/20; H04B1/707; H04B14/00; H04J11/00; H04J13/00; H04J13/18; H04L27/34; (IPC1-7): H04J13/00; H04L27/20
Domestic Patent References:
| JP8321804A | ||||
| JP9181648A | ||||
| JP10107692A | ||||
| JP7506469A |
Other References:
【文献】国際公開95/23464(WO,A1)
【文献】国際公開95/23459(WO,A1)
【文献】国際公開95/23459(WO,A1)
Attorney, Agent or Firm:
Toru Seya (1 outside)