System and method for extending the operating range and/or increasing the bandwidth of a communication link

• US 6,731,678 B1
• Filed: 10/30/2000
• Issued: 05/04/2004
• Est. Priority Date: 10/30/2000
• Status: Expired due to Fees

• Current Assignee: Sprint Communications Company LP (Deutsche Telekom AG)
• Original Assignee: Sprint Communications Company LP (Deutsche Telekom AG)
• Inventors: Kaplan, Martin J., White, Albert L.
• Primary Examiner(s): Tran, Khai
• Assistant Examiner(s): TRAN, KHANH C
• Application Number:
  US09/699,919
• Time in Patent Office: 1,282 Days
• Field of Search: 375/219, 375/220, 375/222, 375/260, 375/225, 375/295, 375/316, 379/93.01, 379/93.07, 379/93.08, 379/93.09, 379/93.11, 379/100.12, 370/320, 370/334, 370/335, 370/342, 370/441, 370/480, 370/485, 370/490, 455/132, 455/135, 455/275, 455/279.1
• US Class Current: 375/219
• CPC Class Codes: H04L 5/0007 the frequencies being orthogonal, e.g. OFDM(A), DMT
• CPC Class Codes: H04L 5/143 for modulated signals H04L5/1469 takes precedence
• CPC Class Codes: H04L 5/16 Half-duplex systems; Simplex/duplex switching; Transmission of break signals non-automatically inverting the direction of transmission

Abstract

A system and method for extending the operating range and/or increasing the bandwidth of a communication link. The communication link may consist of any two communication devices that are connected by two or more separate “band limited” communication paths for the transmission of information therebetween. In operation, the communication devices use a “frequency split scheme” to divide the information transmitted between the devices into two or more signals, each of which is transmitted over one of the communication paths. A “frequency foldback scheme” may also be used to shift the information from the higher frequencies to the lower frequencies of each respective signal, thereby taking advantage of the fact that more information can be carried in the lower frequencies. By using these schemes, it is possible to extend the operating range of the communication link and/or transmit a greater amount of information over the communication paths to thereby increase the bandwidth of the communication link.

Claims

1. A communication system, comprising:

(a) a first communication device;

(b) a second communication device located a distance from said first communication device; and

(c) two or more separate communication paths connecting said first and second communication devices for the transmission of information therebetween;

(d) wherein said first communication device is adapted to divide said information into two or more signals for transmission over a different one of said communication paths, wherein said information is assigned to a plurality of subcarriers on each one of said communication paths in such a manner as to enable said distance between said first and second communication devices to be extended, and wherein said second communication device is adapted to receive said signals from said communication paths and extract said information from said subcarriers on each of said communication paths.

2. The communication system of claim 1, wherein said first and second communication devices are adapted to increase the power level of each of said signals transmitted over said communication paths to thereby enable said distance between said first and second communication devices to be extended.

3. The communication system of claim 1, wherein said first and second communication devices are adapted to assign said information to a plurality of lower frequency subcarriers on each of said communication paths to thereby enable a greater amount of said information to be transmitted between said first and second communication devices.

4. The communication system of claim 3, wherein the transmission of said signals between said first and second communication devices is performed in accordance with an analog modulation scheme.

5. The communication system of claim 3, wherein the transmission of said signals between said first and second communication devices is performed in accordance with a discrete multi-tone modulation scheme.

6. The communication system of claim 1, wherein each of said communication paths comprises a metallic twisted wire pair.

7. The communication system of claim 1, wherein each of said communication paths comprises a coaxial cable.

8. The communication system of claim 1, wherein each of said communication paths comprises a single-mode fiber optic cable.

9. The communication system of claim 1, wherein each of said communication paths comprises a multi-mode fiber optic cable.

10. The communication system of claim 1, wherein each of said communication paths comprises an RF path.

11. The communication system of claim 10, wherein each RF path has a fixed frequency range.

12. The communication system of claim 10, wherein each RF path comprises a CDMA radio channel.

13. An assymetric digital subscriber line (“

ADSL”

) transceiver system for transmitting information between a central office and a customer premise, comprising;

(a) a central office ADSL transceiver unit (“

ATU-C”

) located at said central office;

(b) a remote ADSL transceiver unit (“

ATU-R”

) located a distance from said central office at said customer premise; and

(c) two or more metallic twisted wire pairs connecting said ATU-C and said ATU-R for the transmission of said information therebetween;

(d) wherein said ATU-C and said ATU-R are each adapted to divide said information into two or more signals, each of which is transmitted over a different one of said metallic twisted wire pairs, and wherein said ATU-C and said ATU-R are also each adapted to receive said divided signals from said metallic twisted wire pairs and extract said information therefrom.

14. The ADSL transceiver system of claim 13, wherein said ATU-C and said ATU-R are each adapted to divide said information into said two or more signals in such a manner as to enable said distance between said ATU-C and said ATU-R to be extended.

15. The ADSL transceiver system of claim 13, wherein said ATU-C and said ATU-R are each adapted to divide said information into said two or more signals in such a manner as to enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.

16. The ADSL transceiver system of claim 13, wherein said ATU-C and said ATU-R are each adapted to use a discrete multi-tone (“

DMT”

) modulation scheme whereby said information is carried in a plurality of DMT subcarriers within a specified frequency range over said metallic twisted wire pairs.

17. The ADSL transceiver system of claim 16, wherein said DMT subcarriers are utilized to carry said information over said metallic twisted wire pairs such that the power level of said signals can be increased to thereby enable said distance between said ATU-C and said ATU-R to be extended.

18. The ADSL transceiver system of claim 17, wherein said DMT subcarriers utilized to carry said information over said metallic twisted wire pairs comprise the DMT subcarriers located in a lower portion of said specified frequency range of each of said metallic twisted wire pairs to thereby enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.

19. The ADSL transceiver system of claim 16, wherein said DMT subcarriers are utilized to carry said information over said metallic twisted wire pairs to thereby enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.

20. A communication system for transmitting information between a first location and a second location, comprising:

(a) first communication means located at said first location for dividing said information into two or more signals for transmission to said second location;

(b) second communication means located a distance from said first communication means at said second location for receiving said signals and extracting said information therefrom; and

(c) two or more communication paths connecting said first and second communication means such that each of said signals is transmitted over a different one of said communication paths, wherein said specified wherein said information is assigned to a plurality of subcarriers on each of said communication paths in such a manner as to enable said distance between said first and second communication devices to be extended.

21. The communication system of claim 20, wherein said first and second communication means increase the power level of said signals transmitted over said communication paths to thereby enable said distance between said first and second communication means to be extended.

22. The communication system of claim 20, wherein said first and second communication means are each adapted to assign said information to a plurality of lower frequency subcarriers on each of said communication paths to thereby enable a greater amount of said information to be transmitted between said first and second locations.

23. A method for transmitting information between a first communication device and a second communication device located a distance apart over two or more separate communication paths, comprising the steps of:

(a) dividing said information into two or more signals for transmission over a different one of said communication paths by assigning said information to a plurality of subcarriers on each of said communication paths in such a manner as to allow the power level of said signals to be increased to thereby enable said distance between said first and second communication devices to be extended;

(b) transmitting each of said signals over said communication paths;

(c) receiving said signals from said communication paths; and

(d) extracting said information from said subcarriers on each of said communication paths.

24. The method of claim 23, wherein said information is divided into said two or more signals in accordance with an analog modulation scheme.

25. The method of claim 24, wherein said information is assigned to a plurality of lower frequency subcarriers on each of said communication paths to thereby enable a greater amount of said information to be transmitted between said first and second communication devices.

26. A method for transmitting information between a central office ADSL transceiver unit (“

ATU-C”

) and a remote ADSL transceiver unit (“

ATU-R”

) located a distance apart over two or more metallic twisted wire pairs, comprising the steps of;

(a) dividing said information into two or more signals for transmission over a different one of said metallic twisted wire pairs by assigning said information to a plurality of subcarriers on each of said twisted wire pairs;

(b) transmitting each of said signals over said metallic twisted wire pairs;

(c) receiving said signals from said metallic twisted wire pairs; and

(d) extracting said information from said subcarriers on each of said metallic twisted wire pairs.

27. The method of claim 26, wherein said information is divided into said two or more signals in such a manner as to enable said distance between said ATU-C and said ATU-R to be extended.

28. The method of claim 26, wherein said information is divided into said two or more signals in such a manner as to enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.

29. The method of claim 26, wherein said information is divided into said two or more signals in accordance with a discrete multi-tone (“

DMT”

) modulation scheme.

30. The method of claim 29, wherein said information is divided into said two or more signals by assigning said information to a plurality of DMT subcarriers in such a manner that the power level of said signals can be increased to thereby enable said distance between said ATU-C and said ATU-R to be extended.

31. The method of claim 30, wherein said information is assigned to a plurality of lower frequency DMT subcarriers to thereby enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.

32. The method of claim 29, wherein said information is divided into said two or more signals by assigning said information to a plurality of DMT subcarriers in such a manner as to enable a greater amount of said information to be transmitted between said ATU-C and said ATU-R.