Apparatus and method for communication over power lines

• US 9,142,961 B1
• Filed: 08/26/2011
• Issued: 09/22/2015
• Est. Priority Date: 09/10/2010
• Status: Expired due to Fees

• Current Assignee: U.S. Government Administrator of NASA (Government of the United States of America)
• Original Assignee: United States Administrator of National Aeronautics and Space Administration
• Inventors: Krasowski, Michael J., Prokop, Norman F., Greer, Lawrence C. III, Nappier, Jennifer M.
• Primary Examiner(s): DEBERADINIS, ROBERT L
• Application Number:
  US13/218,847
• Time in Patent Office: 1,488 Days
• Field of Search: 307/3
• US Class Current: 1/1
• CPC Class Codes: H02J 3/02 using a single network for simultaneous distribution of power at different frequencies; using a single network for simultaneous distribution of ac power and of dc power
• CPC Class Codes: H04B 1/04 Circuits
• CPC Class Codes: H04B 2001/0416 having gain or transmission power control
• CPC Class Codes: H04B 2203/5458 Monitor sensor; Alarm systems
• 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

Abstract

An apparatus and method are provided for communicating over power lines. The apparatus includes a coupling modem that is situated between a power line and a device. The coupling modem is configured to demodulate a signal received from the power line into a sine signal and a cosine signal. The coupling modem is also configured to modulate a communicated bit stream received from the device into a transmitted signal in order to impose the transmitted signal onto the power line.

Claims

1. An apparatus, comprising:

a modem situated between a power line and a device, the modem configured to;

demodulate a signal received from the power line into a first signal and a second signal which are linearly and nonlinearly processed to create a bit stream for transmission to the device; and

modulate a bit stream received from the device into a transmitted signal in order to impose the transmitted signal onto the power line.

2. The apparatus of claim 1, wherein the modem comprises a demodulator and a modulator.

3. The apparatus of claim 2, wherein the demodulator comprises a plurality of resistors and a switch, and the demodulator is configured to demodulate the received signal into the first signal and the second signal using a clock cycle at frequencies of interest.

4. The apparatus of claim 3, wherein the plurality of resistors are equal.

5. The apparatus of claim 2, wherein the modulator comprises a gate and an inverter at an input of the gate, and the modulator is configured to receive the communicated bit stream from the device and generate the transmitted signal by gating a clock frequency.

6. The apparatus of claim 1, further comprising:

a signal averaging unit configured to receive the first and the second signals from the modem and calculate direct current values of the first and second signals;

an absolute value unit configured to receive the direct current values of the first and the second signals and determine absolute values of the first and second signals; and

a magnitude unit configured to receive the absolute values of the first and second signals and determine a magnitude of the first and second signals.

7. The apparatus of claim 6, further comprising:

a discriminator and automatic gain control unit configured to receive the magnitude of the first and the second signals and create a bit stream of data to be transmitted to the device.

14. The method of claim 6, further comprising:

receiving, at a discriminator and automatic gain control unit, the magnitude of the first and the second signals; and

creating a bit stream of data to be transmitted to the device.

8. A method, comprising:

demodulating, by a modem, a signal received from a power line into a first signal and a second signal which are linearly and nonlinearly processed to create a bit stream for transmission to a device; and

modulating a bit stream received from the device into a transmitted signal in order to impose the transmitted signal onto the power line.

9. The method of claim 8, wherein the demodulating of the received signal further comprises:

demodulating the received signal into the first signal and a second signal using a clock cycle at frequencies of interest.

10. The method of claim 8, wherein the modulating further comprises:

receiving the bit stream from the device and generating the transmitted signal by gating a clock frequency.

11. The method of claim 8, further comprising:

receiving, at a signal averaging unit, the first and the second signals from the modem; and

calculating direct current values of the first and second signals.

12. The method of claim 11, further comprising:

receiving, at a absolute value unit, the direct current values of the first and second signals; and

determining absolute values of the first and second signals.

13. The method of claim 12, further comprising:

receiving, at a magnitude unit, the absolute values of the first and second signals; and

determining a magnitude of the first and second signals.

15. An apparatus, comprising:

a demodulator configured to receive a signal from a power line and demodulate the signal into a first signal and a second signal using a quadrature clock; and

a modulator configured to receive a bit stream of data and a clock signal to generate a transmission signal for transmission onto the power line.

16. The apparatus of claim 15, wherein the demodulator further comprises:

a plurality of resistors that are equal; and

a switch configured to allow the first and the second signals to pass through when the switch is open and invert the first and the second signals when the switch is closed.

17. The apparatus of claim 15, wherein the quadrature clock comprises two clock streams that are 90 degrees out of phase with a 50 percent duty cycle.

18. The apparatus of claim 15, wherein the modulator comprises a gate with a first inverter and a second inverter at a front of the gate.

19. The apparatus of claim 18, wherein the first inverter is configured to receive the bit stream of data from the device, and the second inverter is configured to receive the clock signal from the device.

20. The apparatus of claim 15, wherein the modulator is configured to gate the clock signal with the bit stream in order to generate the transmission signal such that the transmission signal can be imparted onto the power line.