System and method for data communication over power lines

• US 7,986,711 B2
• Filed: 10/11/2005
• Issued: 07/26/2011
• Est. Priority Date: 04/08/2003
• Status: Active Grant

• Current Assignee: ACN Advanced Communications Network SA
• Original Assignee: ACN Advanced Communications Network SA
• Inventors: Jamin, Antony, Horvath, Stephan
• Primary Examiner(s): Wu; Jianye
• Application Number:
  US11/246,560
• Publication Number:
  US 20060146866A1
• Time in Patent Office: 2,114 Days
• Field of Search: 370/464
• US Class Current: 370/468
• CPC Class Codes: H04B 2203/5416 by adding signals to the wave form of the power source
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines
• CPC Class Codes: H04L 5/06 the signals being represented by different frequencies combined with time-division multiplexing H04L5/26

Abstract

A system and method for broadband communications over power lines has a low-voltage transformer for the house connection unit and/or the electricity distribution inside the house. The system method allow for several parallel asynchronous data communications in different sub-channels with individual transmit power in each sub-channel. Sub-channel separation uses pass-band filters with high stop-band attenuation. High data rate in each sub-channel is achieved through the use of discrete wavelet multi-tone modulation. Coarse synchronization in each sub-channel and the optimization of the coefficients of the time-domain equalizer are carried out using a training sequence.

Claims

1. A method for data communication, comprising the step of:

from a plurality of senders to a plurality of receivers being connected over a single electric power network having a determined data transmission channel bandwidth in a frequency band of 1.6-40 MHz, simultaneously asynchronously transmitting data over any of a plurality of parallel peer-to-peer transmission channels established on said single electric power network between said plurality of senders and said plurality of receivers;

said channel bandwidth being dynamically divided into a plurality of non-overlapping sub-channels having different frequency bandwidths and using band-pass filters, each of said parallel peer-to-peer transmission channels using a different one of said sub-channels;

wherein each of the plurality of senders detects current data transmission activity on a plurality of said sub-channels and selects a sub-channel free of any current data transmission activity for transmitting data.

2. The method of claim 1, further comprising modulating said data with a Discrete Cosine Modulation filter bank.

3. The method of claim 1, further comprising modulating said data with a Wavelet Packet filter bank.

4. The method of claim 1, further comprising synchronizing each of said receivers with a corresponding sender.

5. The method of claim 4, said synchronizing being performed with a training sequence known from said receivers and transmitted by said corresponding senders.

6. The method of claim 1, data transmission over each of said peer-to-peer transmission channels being performed at a different transmission power.

7. The method of claim 6, said transmission power being adapted to the signal attenuation along the corresponding peer-to-peer transmission channel.

8. The method of claim 1, further comprising encrypting said data using a public-private key encryption method.

19. The method of claim 1, wherein said detecting comprises measuring signal energy for a selected one of the plurality of sub-channels.

20. The method of claim 1, comprising the steps performed by the sender of detecting current data transmission activity on a plurality of said sub-channels, determining which of the plurality of sub-channels are free of any data transmission activity, and selecting one of the plurality of sub-channels determined to be free of any data transmission activity.

21. The method of claim 20, wherein said selecting comprises selecting the best sub-channel of the plurality of sub-channels determined to be free of any data transmission activity based on at least one of bandwidth, attenuation characteristics and noise.

22. The method of claim 1, wherein each sub-channel has individual transmit power.

9. A system for data communication comprising:

a plurality of bi-directional communication devices for transmitting and/or receiving data over an electric power network having a determined data transmission channel bandwidth in a frequency band of 1.6-40 MHz;

said bi-directional communication devices each comprising a transceiver system designed for asynchronously transmitting data over any of a plurality of parallel peer-to-peer transmission channels established on said electric power network between said plurality of bi-directional communication devices;

wherein the system is arranged to dynamically divide said channel bandwidth into a plurality of non-overlapping sub-channels having different frequency bandwidths and using band-pass filters, each of said peer-to-peer transmission channels being established using one of said plurality of non-overlapping sub-channels, wherein each of the plurality of bi-directional communication devices detects current data transmission activity on a plurality of said sub-channels and selects a sub-channel free of any current data transmission activity for transmitting data.

10. The system of claim 9, each of said plurality of bi-directional communication devices comprising a sender and/or a receiver.

11. The system of claim 10, said sender and/or receiver comprising a filter bank for modulating and/or demodulating the data to be transmitted and/or received over said sub-channel using a plurality of sub-carriers.

12. The system of claim 11, said transceiver system being configured so as to transmit at different data rates and/or transmit power level for each one of said plurality of sub-carriers, depending on the transmission characteristics in the corresponding sub-carrier frequency bandwidth.

13. The system of claim 11, said filter bank being a Discrete Cosine Modulation filter bank.

14. The system of claim 11, said filter bank being a Wavelet Packet filter bank.

15. The system of claim 10, said receiver comprising a synchronization device for synchronizing said receiver with a corresponding sender.

16. The system of claim 15, said receiver being synchronized with the help of a training sequence known from the receiver and transmitted by the corresponding sender.

17. A method for data communication, comprising:

from a plurality of senders to a plurality of receivers being connected over a single electric power network having a determined data transmission channel bandwidth in a frequency band of 1.6-40 MHz, simultaneously asynchronously transmitting data over a plurality of parallel peer-to-peer transmission channels established on said single electric power network between said plurality of senders and said plurality of receivers;

said channel bandwidth being dynamically divided into a plurality of non-overlapping sub-channels, each of said parallel peer-to-peer transmission channels using a different one of said sub-channels having different frequency bandwidths and using band-pass filters and comprising a step of discrete wavelet multi-tone modulating data, within said parallel peer-to-peer transmission channels, over a plurality of sub-carriers within the frequency bandwidth available in the sub-channel used by said parallel peer-to-peer transmission channel;

wherein each of the plurality of senders detects current data transmission activity on a plurality of said sub-channels and selects a sub-channel free of any current data transmission activity for transmitting data.

18. A system for data communication comprising:

a plurality of bi-directional communication devices for transmitting and/or receiving data over an electric power network having a determined data transmission channel bandwidth in a frequency band of 1.6-40 MHz;

said bi-directional communication devices each comprising a transceiver system designed for asynchronously transmitting data over a plurality of parallel peer-to-peer transmission channels established on said electric power network between said plurality of bi-directional communication devices, wherein each of said peer-to-peer transmission channels being established using a different one of non-overlapping sub-channels having different frequency bandwidths and using band-pass filters; and

wherein each of said bi-directional communication devices detects current data transmission activity on a plurality of said sub-channels and selects a sub-channel free of any current data transmission activity for transmitting data, and comprises a filter bank for discrete wavelet multi-tone modulating and/or demodulating the data to be transmitted and/or received over said sub-channel using a plurality of sub-carriers, said transceiver system being configured so as to transmit at different data rates and/or transmit power level for each one of said plurality of sub-carriers, depending on the transmission characteristics in the corresponding sub-carrier frequency bandwidth.

23. A power line modem comprising:

a power line network that has a bandwidth in a frequency band of 1.6-40 MHz connecting to the power line modem;

a sender;

a receiver; and

an activity detector circuit, wherein the activity detector circuit is arranged to detect presence of a data communication activity in a plurality of non-overlapping sub-channels channels having different frequency bandwidths and using band-pass filters obtained by dividing said bandwidth of the power line network;

wherein the sender detects current data transmission activity on one of said plurality of said sub-channels and to select a free sub-channel that is free from data communication activity, to be employed for transmission, wherein the sender comprises a discrete cosine modulated filter bank or a wavelet packet modulated filter bank arranged to modulate the data to be transmitted over a plurality of sub-carriers, and a modulator arranged to digitally upshift the serial output of said discrete cosine modulated filter bank or a wavelet packet modulated filter bank in said selected free sub-channel.