Transmission and reception system for television signal

Abstract

Abstract PURPOSE:To improve largely picture quality by frequency-converting a high frequency luminance signal exceeding the transmission band width by a specific frequency and multiplexing the high frequency luminance signal onto a television signal in the transmission band. CONSTITUTION:A luminance signal Y and color difference signals I, Q are outputted from a matrix 101. A prescribed band is limited to the signals I, Q by LPFs 102, 103 and the spread of a vector is limited by band limit circuits 104, 105, orthogonal modulation is applied by an orthogonal modulation circuit 107 to form a chrominance carrier signal. On the other hand, components below 4.2MHz in the luminance signal Y passes through an LPF 106 and is fed to an adder circuit 108. A high frequency luminance signal YH exceeding 4.2MHz is extracted by a BPF 111 and the spread of the spectrum is limited by a band limit circuit 112 and subjected to frequency modulation by a balanced modulation circuit 113 and a BPF 114. Thus, the signals YH and Y are superimposed on each other. In this case, the carrier frequency mu0 to the circuit 113 is to be selected as an integral number of multiple of the horizontal synchronizing frequency fH.

Inventors

• 👤 Shigemitsu Higuchi
• 👤 Akira Shibata

Bibliographic Details