Radio communication system

Abstract

Abstract PURPOSE:To transmit a digital signal without affecting the transmission of a picture signal, by transmitting the digital signal in the direction opposite to the transmitting direction of the picture signal by making use of the horizontal synchronizing signal of the picture signal. CONSTITUTION:A digital signal DG is applied to a velocity converting circuit 32. The synchronizing signal extracted by a synchronizing signal adder circuit 30 is applied to the circuit 32 via a delay circuit 31. At the same time, a clock CLK is applied to the circuit 32. The signal DG is applied to a modulator 33 only in the period of a horizontal synchronizing signal. The modulator 33 modulates the digital signal with the output of a local oscillator 34. While the signal DG is received by an antenna 7 at the transmitting side of the picture signal. Then the signal DG is applied to a mixer 9 to be mixed with the picture signal given from a branching circuit 4 and then converted into an IF. Then the clock reproduced 14 after IF amplified 10 and velocity converted 13, and the digital signal within the period of a horizontal synchronizing signal is converted into continuous digital signals by an extracted synchronizing signal.

Inventors

• 👤 Isao Nakazawa
• 👤 中沢　勇夫

Bibliographic Details