Transformer coupler for communication over various lines

• US 5,717,685 A
• Filed: 06/02/1995
• Issued: 02/10/1998
• Est. Priority Date: 04/28/1989
• Status: Expired due to Fees

• Current Assignee: Satius Holding, Inc. (Satius, Inc.)
• Original Assignee: Videocom, Inc.
• Inventors: Abraham, Charles
• Primary Examiner(s): Olms, Douglas W.
• Assistant Examiner(s): HOM, SHICK C
• Application Number:
  US08/458,229
• Time in Patent Office: 984 Days
• Field of Search: 370/30, 370/31, 370/26, 370/32, 340/310.01, 340/310.03, 340/310.05, 340/310.06, 340/310.07, 340/310.08, 340/825.51, 340/825.54, 340/870.17, 340/870.28, 333/177, 336/182
• US Class Current: 370/276
• CPC Class Codes: H04B 2203/5416 by adding signals to the wave form of the power source
• CPC Class Codes: H04B 2203/5425 improving S/N by matching impedance, noise reduction, gain control
• CPC Class Codes: H04B 2203/5441 Wireless systems or telephone
• CPC Class Codes: H04B 2203/5445 Local network
• CPC Class Codes: H04B 2203/545 Audio/video application, e.g. interphone
• CPC Class Codes: H04B 2203/5483 using coupling circuits
• CPC Class Codes: H04B 2203/5491 using filtering and bypassing
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04B 3/542 the information being in digital form
• CPC Class Codes: H04B 3/56 Circuits for coupling, blocking, or by-passing of signals

Abstract

Apparatus for electrical line communication that includes a coupler at each of two or more locations along a pair of lines, the coupler having capacitive circuits serially connected with an air-core transformer. The capacitive circuit is designed to resonate with the air-core transformer at a preselected frequency. A transmitter, receiver and modem may also be provided at each location. The apparatus incorporates a novel phase linear coupler which eliminates noise and is matched resistively to the characteristic impedance of the line at a preselected frequency. This apparatus therefore linearizes communication on the line and allows high speed data and voice communication over long distances.

Claims

1. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising:

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

wherein said coupler means communicates the carrier signal having a first preselected frequency less than 90 KHz and a linear phase bandwidth of approximately 7 KHz.

2. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising;

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

wherein said coupler means communicates the carrier signal having a first preselected frequency approximately 30 KHz and a linear phase bandwidth of approximately 6 KHz.

3. A communication apparatus for communicating electrical signals through a pair of electrical lines having a characteristic impedance comprising:

first modem means for producing a modulated carrier signal having a first preselected frequency and demodulating a modulated carrier signal having a second preselected frequency;

first transmitter means having an output impedance, connected to the first modem means, for transmitting the modulated carrier signal at a first preselected frequency;

first receiver means having an input impedance, connected to the first modem means, for receiving the modulated carrier signal having a second preselected frequency;

first coupler means connected between the electrical lines and said first transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said first coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

second modem means for producing a modulated carrier signal having a second preselected frequency and demodulating a modulated carrier signal having a first preselected frequency;

second transmitter means having an output impedance, connected to the second modem means, for transmitting the modulated carrier signal at a second preselected frequency;

second receiver means having an input impedance, connected to the second modem means, for receiving the modulated carrier signal having a first preselected frequency;

second coupler means connected between the electrical lines and said second transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines;

said second coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

wherein the linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion;

said air-core transformer means comprising primary coil having a first diameter, and secondary coil having a second smaller diameter;

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils;

wherein said first and second coupler means communicates the carrier signals having preselected frequencies less than 35 KHz each and a linear phase bandwidth of approximately 6 KHz.

4. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising:

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

demodulator means for demodulating said carrier signal on said electrical lines to produce a demodulated carrier signal having a second preselected frequency;

receiver means having an input impedance connected to said demodulator means for receiving the modulated carrier signal;

second coupler means connected between the electrical line and the receiver means for matching the input impedance of said receiver means to the characteristic impedance of the electrical line;

said second coupler means comprising linear phase means for communicating the modulated carrier signal to the receiver means without phase distortion and capacitor means for resonating with the linear phase means at the second preselected frequency;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion,

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter,

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils,

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said primary coil has a resistive component and said resistive component of said primary coil of said transmitter means is 1 ohm and said resistive component of said primary coil of said receiver means is 3 ohms for full duplex communication.

5. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising:

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

demodulator means for demodulating said carrier signal on said electrical lines to produce a demodulated carrier signal having a second preselected frequency;

receiver means having an input impedance connected to said demodulator means for receiving the modulated carrier signal;

second coupler means connected between the electrical line and the receiver means for matching the input impedance of said receiver means to the characteristic impedance of the electrical line;

said second coupler means comprising linear phase means for communicating the modulated carrier signal to the receiver means without phase distortion and capacitor means for resonating with the linear phase means at the second preselected frequency;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion,

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter,

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils,

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said primary coil has a resistive component and said resistive component of said primary coil of said transmitter means is 1 ohm and said resistive component of said primary coil of said receiver means is 1 ohm for half duplex communications.

6. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising:

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

demodulator means for demodulating said carrier signal on said electrical lines to produce a demodulated carrier signal having a second preselected frequency;

receiver means having an input impedance connected to said demodulator means for receiving the modulated carrier signal;

second coupler means connected between the electrical line and the receiver means for matching the input impedance of said receiver means to the characteristic impedance of the electrical line;

said second coupler means comprising linear phase means for communicating the modulated carrier signal to the receiver means without phase distortion and capacitor means for resonating with the linear phase means at the second preselected frequency;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion,

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter,

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils,

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said electrical line is a high voltage power line and said primary coil has a resistive component and wherein said resistive component of said primary coil of said transmitter means is 5 ohms and said resistive component of said primary coil of said receiver means is 10 ohms for full duplex communications.

7. A communications apparatus for communicating electrical signals through an electrical line having a characteristic impedance comprising:

modulator means for modulating the electrical signals to produce a modulated carrier signal having a first preselected frequency;

transmitter means having an output impedance, connected to said modulator means for transmitting the modulated carrier signal;

first coupler means connected between the electrical line and the transmitter means for matching the output impedance of said transmitter means to the characteristic impedance of the electrical line;

said first coupler means comprising linear phase means for communicating the modulated carrier signal to the electrical line without phase distortion and capacitor means for resonating with the linear phase means at the first preselected frequency;

demodulator means for demodulating said carrier signal on said electrical lines to produce a demodulated carrier signal having a second preselected frequency;

receiver means having an input impedance connected to said demodulator means for receiving the modulated carrier signal;

second coupler means connected between the electrical line and the receiver means for matching the input impedance of said receiver means to the characteristic impedance of the electrical line;

said second coupler means comprising linear phase means for communicating the modulated carrier signal to the receiver means without phase distortion and capacitor means for resonating with the linear phase means at the second preselected frequency;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion,

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter,

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils,

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said electrical line is a high voltage power line and said primary coil has a resistive component and wherein said resistive component of said primary coil of said transmitter means is 5 ohms and said resistive component of said primary coil of said receiver means is 5 ohms for half duplex communications.

8. A communication apparatus for communicating electrical signals through a pair of electrical lines having a characteristic impedance comprising:

first modem means for producing a modulated carrier signal having a first preselected frequency and demodulating a modulated carrier signal having a second preselected frequency;

first transmitter means having an output impedance, connected to the first modem means, for transmitting the modulated carrier signal at a first preselected frequency;

first receiver means having an input impedance, connected to the first modem means, for receiving the modulated carrier signal having a second preselected frequency;

first coupler means connected between the electrical line and said first transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said first coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

second modem means for producing a modulated carrier signal having a second preselected frequency and demodulating a modulated carrier signal having a first preselected frequency;

second transmitter means having an output impedance, connected to the second modem means, for transmitting the modulated carrier signal at a second preselected frequency;

second receiver means having an input impedance, connected to the second modem means, for receiving the modulated carrier signal having a first preselected frequency;

second coupler means connected between the electrical lines and said second transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said second coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a phase linear means for communicating the carrier signals without phase distortion;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion;

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter;

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils;

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said primary coil has a resistive component and said resistive component of said primary coil of said transmitter means is 1 ohm and said resistive component of said primary coil of said receiver means is 3 ohms for full duplex communications.

9. A communication apparatus for communicating electrical signals through a pair of electrical lines having a characteristic impedance comprising:

first modem means for producing a modulated carrier signal having a first preselected frequency and demodulating a modulated carrier signal having a second preselected frequency;

first transmitter means having an output impedance, connected to the first modem means, for transmitting the modulated carrier signal at a first preselected frequency;

first receiver means having an input impedance, connected to the first modem means, for receiving the modulated carrier signal having a second preselected frequency;

first coupler means connected between the electrical line and said first transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said first coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

second modem means for producing a modulated carrier signal having a second preselected frequency and demodulating a modulated carrier signal having a first preselected frequency;

second transmitter means having an output impedance, connected to the second modem means, for transmitting the modulated carrier signal at a second preselected frequency;

second receiver means having an input impedance, connected to the second modem means, for receiving the modulated carrier signal having a first preselected frequency;

second coupler means connected between the electrical lines and said second transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said second coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a phase linear means for communicating the carrier signals without phase distortion;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion;

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter;

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils;

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said primary coil has a resistive component and said resistive component of said primary coil of said transmitter means is 1 ohm and said resistive component of said primary coil of said receiver means is 1 ohm for half duplex communications.

10. A communication apparatus for communicating electrical signals through a pair of electrical lines having a characteristic impedance comprising:

first modem means for producing a modulated carrier signal having a first preselected frequency and demodulating a modulated carrier signal having a second preselected frequency;

first transmitter means having an output impedance, connected to the first modem means, for transmitting the modulated carrier signal at a first preselected frequency;

first receiver means having an input impedance, connected to the first modem means, for receiving the modulated carrier signal having a second preselected frequency;

first coupler means connected between the electrical line and said first transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said first coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

second modem means for producing a modulated carrier signal having a second preselected frequency and demodulating a modulated carrier signal having a first preselected frequency;

second transmitter means having an output impedance, connected to the

second modem means, for transmitting the modulated carrier signal at a second preselected frequency;

second receiver means having an input impedance, connected to the second modem means, for receiving the modulated carrier signal having a first preselected frequency;

second coupler means connected between the electrical lines and said second transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said second coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a phase linear means for communicating the carrier signals without phase distortion;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion;

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter;

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils;

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said electrical line is a high voltage power line and said primary coil has a resistive component and wherein said resistive component of said primary coil of said transmitter means is 5 ohms and said resistive component of said primary coil of said receiver means is 10 ohms for full duplex communications.

11. A communication apparatus for communicating electrical signals through a pair of electrical lines having a characteristic impedance comprising:

first modem means for producing a modulated carrier signal having a first preselected frequency and demodulating a modulated carrier signal having a second preselected frequency;

first transmitter means having an output impedance, connected to the first modem means, for transmitting the modulated carrier signal at a first preselected frequency;

first receiver means having an input impedance, connected to the first modem means, for receiving the modulated carrier signal having a second preselected frequency;

first coupler means connected between the electrical line and said first transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said first coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a linear phase means for communicating the carrier signals without phase distortion;

second modem means for producing a modulated carrier signal having a second preselected frequency and demodulating a modulated carrier signal having a first preselected frequency;

second transmitter means having an output impedance, connected to the second modem means, for transmitting the modulated carrier signal at a second preselected frequency;

second receiver means having an input impedance, connected to the second modem means, for receiving the modulated carrier signal having a first preselected frequency;

second coupler means connected between the electrical lines and said second transmitter and receiver means for matching the impedance of said devices to the characteristic impedance of the electrical lines,

said second coupler means comprising two LCR circuits each consisting of at least one capacitor and at least one resistor connected in parallel to each other and in series to the electrical lines and a phase linear means for communicating the carrier signals without phase distortion;

wherein said linear phase means comprises air-core transformer means for communicating said modulated carrier signal without phase distortion;

said air-core transformer means comprising primary coil having a first diameter and secondary coil having a second smaller diameter;

said secondary coil extending coaxially within said primary coil such that an air-gap is created between said primary and said secondary coils;

further comprising capacitor means connected between said primary coil and said electrical line wherein said primary coil and said capacitor means are matched to the characteristic impedance of said electrical line at a preselected bandwidth;

wherein said electrical line is a high voltage power line and said primary coil has a resistive component and wherein said resistive component of said primary coil of said transmitter means is 5 ohms and said resistive component of said primary coil of said receiver is 5 ohm for half duplex communications.