Title:
ORTHOGONAL MULTIPLEX TRANSMISSION SYSTEM AND SIGNAL GENERATOR USED FOR TRANSMITTER THEREOF AND SIGNAL REPRODUCING DEVICE USED FOR RECEIVER THEREOF
Document Type and Number:
Japanese Patent JPH02156787
Kind Code:
A
Abstract:
PURPOSE:To reduce disturbance of a multiplex signal onto a video signal of a television receiver by applying spectrum suppression processing to a multiplex signal subject to digital coding, applying modulation so as to invert the phase of an adjacent data and applying amplitude modulation to an orthogonal carrier in the relation of orthogonal phase with a video carrier. CONSTITUTION:A multiplex digital signal is fed to an input terminal 111, a digital signal processing circuit 112 corrects an error caused during the transmission, a digital modulation circuit 113 applies FM, PE digital modulation and a tri-state value conversion circuit 114 converts the binary digital signal into a tri-state digital signal. Moreover, a processing circuit 115 processed the data in the unit of one horizontal scanning period for plural number of times, the data is inverted in the adjacent horizontal scanning period to apply transmission in opposite phase. Then the carrier for video is modulated in the orthogonal relation between the video signal and digitally coded signal. Thus, the disturbance onto the existing television receiver is reduced in the case of multiplexing the multiplex signal.
Inventors:
KISUGI TAKATOSHI
NODA TSUTOMU
HOTTA NOBUTAKA
NODA TSUTOMU
HOTTA NOBUTAKA
Application Number:
JP30997188A
Publication Date:
June 15, 1990
Filing Date:
December 09, 1988
Export Citation:
Assignee:
HITACHI LTD
HITACHI VIDEO ENG
HITACHI VIDEO ENG
International Classes:
H04N7/015; H04N7/00; H04N7/08; H04N7/081; (IPC1-7): H04N7/00; H04N7/08
Attorney, Agent or Firm:
Katsuo Ogawa (1 person outside)