WIRED COMMUNICATIONS SYSTEMS WITH IMPROVED CAPACITY AND SECURITY

• US 20140286489A1
• Filed: 06/09/2014
• Published: 09/25/2014
• Est. Priority Date: 10/19/2011
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Ross, John Anderson Fergus, Hartman, Michael James, Hershey, John Erik, Zinser, Richard Louis
• Granted Patent: US 10,666,623 B2
• Time in Patent Office: Days
• US Class Current: 380/257
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 5/14 Two-way operation using the same type of signal, i.e. duplex
• CPC Class Codes: H04L 63/0428 wherein the data content is protected, e.g. by encrypting or encapsulating the payload

Abstract

Provided are methods and systems of using division-free duplexing (DFD) in a cable communication network. Techniques for applying DFD in a cable communication network may enable data to be transmitted and received over a coaxial cable without using division duplexing techniques. For example, the cable communication network may include DFD enabled network nodes and each subscriber to the cable network may be equipped with a DFD system configured to operate in a DFD mode. In some embodiments, oppositely propagating signals may be transmitted over one frequency channel, and DFD techniques may be used to recover originally transmitted signals. Further, in some embodiments, DFD techniques may be used with encryption methods to increase the security of data transmitted in the cable communication network.

Claims

1. A method comprising:

transmitting first data comprising a cryptovariable in a first direction from a first device to a second device over a cable in a cable communication network;

receiving the first data comprising the cryptovariable at a second device;

transmitting second data from the second device over the cable in a second direction, using a division-free duplexing (DFD) technique, and wherein transmitting the second data from the second device comprises transmitting broadband noise from the second device while the first device transmits the cryptovariable to the second device; and

removing the broadband noise from the first data received at the second device using the DFD techniques to recover the cryptovariable.

2. The method of claim 1, comprising one or more of:

transmitting first encrypted data in the first direction from the first device after transmitting the cryptovariable; and

transmitting second encrypted data in the second direction from the second device after receiving and recovering the cryptovariable.

3. The method of claim 2, comprising:

receiving the first encrypted data at the second device; and

decrypting the first encrypted data using the cryptovariable.

4. The method of claim 3, comprising:

removing the broadband noise from the first encrypted data at the second device before decrypting.

5. The method of claim 1, comprising:

wherein removing the broadband noise from the first data received at the second device comprises using the second data transmitted from the second device as a reference signal.

6. The method of claim 1, wherein the DFD technique comprises:

receiving an analog primary signal from the cable;

receiving an analog reference signal from a transmitter;

converting the analog primary signal into a digital primary signal;

converting the analog reference signal into a digital reference signal; and

processing the digital reference signal with a digital adaptive filter, wherein the digital adaptive filter uses the digital reference signal and digital primary signal as inputs for determining filter weights of the digital adaptive filter to provide an output; and

subtracting the output of the digital adaptive filter from the digital primary signal to generate a digital cancelled signal.

7. The method of claim 1, wherein the first data transmitted in the first direction and the second data transmitted in the second direction are transmitted over the same frequency channel.

8. A cable communication system, comprising:

a plurality of nodes each comprising a division-free duplexing (DFD) system configured such that each of the plurality of nodes is operable in a DFD mode; and

a processor configured to control a mode of operation of each of the plurality of nodes, wherein each of the plurality of nodes connected to the one or more fiber rings is configured to receive a cryptovariable from one of the one or more network nodes.

9. The cable communication system of claim 8, wherein a communication between two or more of the plurality of nodes is transmitted via a coaxial cable.

10. The cable communication system of claim 8, wherein the plurality of nodes comprises one or more network nodes and one or more fiber rings each comprising a plurality of nodes, wherein each of the one or more network nodes are connected to one or more fiber rings.

11. The cable communication system of claim 8, wherein the cryptovariable comprises an algorithm.

12. The cable communication system of claim 8, wherein each of the plurality of nodes connected to the one or more fiber rings is configured to transmit noise while receiving the cryptovariable and use DFD techniques to recover the cryptovariable.

13. The cable communication system of claim 8, wherein the processor is configured to control the transmission of the cryptovariable from one of the one or more network nodes and the receiving of the cryptovariable at each of the plurality of nodes connected to the one or more fiber rings.

14. The cable communication system of claim 8, wherein each of the plurality of nodes in the one or more fiber rings is coupled to a user of the cable communication system.

15. The cable communication system of claim 8, wherein the plurality of nodes each comprise instructions for:

receiving a primary signal;

receiving a reference signal from a transmitter;

processing the reference signal with an adaptive filter, wherein the adaptive filter uses the reference signal and primary signal as inputs for determining filter weights of the adaptive filter to provide an output; and

subtracting the output of the adaptive filter from the primary signal to generate a cancelled signal comprising the cryptovariable.

16. The cable communication system of claim 8, wherein the processor is configured to operate a respective node of the plurality of nodes using a division duplexing scheme.

17. A division-free duplexing (DFD) system comprising:

a receiver capable of receiving an analog primary signal from a coaxial cable in a cable network, wherein the analog signal comprises a cryptovariable;

a transmitter capable of transmitting an analog transmitted signal to the coaxial cable, wherein the analog transmitted signal comprises broadband noise;

a directional coupler capable of sampling a portion of the analog transmitted signal to provide an analog reference signal;

a first analog to digital converter capable of converting the analog primary signal into a digital primary signal;

a second analog to digital converter capable of converting the analog reference signal into a digital reference signal; and

a processor comprising instructions for;

processing the digital reference signal with an adaptive filter, wherein the adaptive filter uses the digital reference and primary signals as inputs for determining filter weights of the adaptive filter to provide an output;

subtracting the output of the adaptive filter from the digital primary signal to generate a digital cancelled signal; and

recovering the cryptovariable from the digital cancelled signal.

18. The DFD system of claim 17, wherein the DFD system is configured to be coupled to a network node in a cable communication network.

19. The DFD system of claim 17, wherein the DFD system is configured to be coupled to a user device of a cable communication network.

20. The DFD system of claim 17, wherein the transmitter is configured to transmit the analog transmitted signal to the coaxial cable on a same frequency from which the receiver receives the analog primary signal.

21. The DFD system of claim 17, wherein the processor further comprises instructions for using the recovered cryptovariable to decrypt encrypted signals received at the receiver.

22. The DFD system of claim 17, wherein the processor further comprises instructions for using the recovered cryptovariable to encrypt signal transmitted from the transmitter.