Patent ID: 6396392
Filing Date: 2002-05-28
Classification: H04B,H04L

Abstract:
A communications apparatus for communicating electric signals through one or more electric lines having a characteristic impedance comprising:a modulator which modulates the electric signals to produce a modulated carrier signal having a first preselected frequency greater than or equal to 200 MHz; a transmitter operatively connected to the modulator and having an output impedance, said transmitter transmitting the modulated carrier signal; a first coupler connected between the electric line and the transmitter, said coupler matching the output impedance of the transmitter to the characteristic impedance of the electric line and communicating the modulated carrier signal to the electric line without significant phase distortion; a receiver having an input impedance, said receiver receiving the modulated carrier signal; a demodulator electrically connected to the receiver, said demodulator producing a demodulated carrier signal having a second preselected frequency greater than or equal to 200 Mhz by demodulating the modulated carrier signal; a second coupler connected between the electric line and the receiver for matching the input impedance of the receiver to the characteristic impedance of the electric line and communicating the modulated carrier signal to the receiver without significant phase distortion; the first coupler comprising a first transformer having a non-magnetic core, said transformer communicating the modulated carrier signal to the electric line without substantial phase distortion, and a coupling capacitor, that resonates with the transformer at the preselected frequency; the second coupler comprises a second transformer having a non-magnetic core which communicates the modulated carrier signal to the receiver without substantial phase distortion, and a coupling capacitor which resonates with the transformer at the preselected frequency; the first coupler comprising: a first conductive plate; a second conductive plate spaced apart from the first conductive plate by the non-magnetic core; a capacitor adapted to be connected between the first conductive plate and the electric line, wherein the first conductive plate and the capacitor are matched to the characteristic impedance of the electric line at a preselected bandwidth; the second coupler comprising: a first conductive plate; a second conductive plate spaced apart from the first conductive plate by the non-magnetic core; and a capacitor adapted to be connected between the first conductive plate and the electric line, wherein the first conductive plate and the capacitor are matched to the characteristic impedance of the electric line at a preselected bandwidth.