US 4,907,218 A · Multiplex signal processing apparatus

Abstract

In a multiplex signal processing apparatus, in the band of a demodulated signal in which a carrier is amplitude-modulated in a vestigial side band by a main signal, another carrier is superposed which is identical in frequency to the first carrier but different in phase by 90.degree. is amplitude-modulated its double side bands by a multiplex signal which is different from the main signal and which is formed into a vestigial side band signal by a nyquist filter. At least either the frequency or polarity of the multiplex signal is inverted on the transmission side by a multiplier, an oscillator and a filter. At least either the frequency or polarity of the multiplex signal is inverted on the reception side by a multiplier, an oscillator and a filter. The reception side has a crosstalk reduction filter for removing crosstalk from the main signal to the multiplex signal.

Claims3

Dependent claims

A multiplex signal processing apparatus on a transmission side, comprising:

a first carrier modulating means for modulating a first carrier by a main signal;
a means for inverting at least one of frequency and polarity of a multiplex signal;
a second carrier modulating means for modulating a second carrier, which is the same in frequency as and different in phase from the first carrier, by an output of said inverting means;
and
a means for adding an output of the first carrier modulating means and an output of the second carrier modulating means to obtain a signal to be transmitted.

2 more elements

Dependencies are inferred from the claim text.

Multiplex signal processing apparatus

Life of this patent

Multiplex signal processing apparatus

Life of this patent

Abstract

Claims3