DMT symbol repetition in the presence of impulse noise

• US 9,621,198 B2
• Filed: 12/03/2014
• Issued: 04/11/2017
• Est. Priority Date: 10/15/2004
• Status: Active Grant

• Current Assignee: TQ Delta LLC (Techquity Capital Management, LLC)
• Original Assignee: TQ Delta LLC (Techquity Capital Management, LLC)
• Inventors: Tzannes, Marcos C.
• Primary Examiner(s): Wong, Linda
• Application Number:
  US14/559,156
• Publication Number:
  US 20150146821A1
• Time in Patent Office: 860 Days
• Field of Search: 375219, 375220, 375222, 375240, 37524026-24027, 375254, 375259, 375267, 375285, 375284, 375278, 375295, 375299, 375316, 375324, 375340, 375346, 375347, 375349, 375358, 455 39, 455 42, 455 45, 455500, 455501, 455517, 455702, 455 91, 455 95, 455101, 455103, 455104, 455112, 4551142
• CPC Class Codes: H04B 1/0475 with means for limiting noise, interference or distortion H04B1/0483 takes precedence
• CPC Class Codes: H04B 3/50 Systems for transmission between fixed stations via two-conductor transmission lines H04B3/54 takes precedence
• CPC Class Codes: H04L 1/0009 by adapting the channel coding H04L1/1812 takes precedence
• CPC Class Codes: H04L 1/0011 applied to payload information
• CPC Class Codes: H04L 1/0026 Transmission of channel quality indication
• CPC Class Codes: H04L 1/0041 Arrangements at the transmitter end
• CPC Class Codes: H04L 1/0045 Arrangements at the receiver end
• CPC Class Codes: H04L 1/0061 Error detection codes
• CPC Class Codes: H04L 1/007 Unequal error protection for format H04L1/0078; for codes per se H03M13/35
• CPC Class Codes: H04L 1/0071 Use of interleaving interleaving per se H03M13/27
• CPC Class Codes: H04L 1/08 by repeating transmission, e.g. Verdan system H04L1/1858 and H04L1/189 take precedence
• CPC Class Codes: H04L 1/20 using signal quality detector
• CPC Class Codes: H04M 11/062 using different frequency bands for speech and other data

Abstract

With the current initialization procedures defined in the VDSL and ADSL standards, even though the xDSL system could operate in Showtime in an impulse noise environment where symbols are being corrupted, the transceivers would not be able to reach Showtime because initialization would fail due to initialization message failure. Through the use of an improved initialization procedure for communication systems, operation in environments with higher levels of impulse noise is possible.

Claims

1. A method, in a multicarrier transceiver, the method comprising:

receiving at the multicarrier transceiver from another multicarrier transceiver over a connected communications channel a first message indicating a repetition rate for DMT symbols;

modulating at least one bit of a second message onto at least one DMT symbol;

determining a CRC (Cyclic Redundancy Checksum) for the second message;

modulating at least one CRC bit of the CRC for the second message onto at the least one DMT symbol;

repeating the at least one DMT symbol with the modulated at least one CRC bit of the CRC for the second message according to the repetition rate indicated in the first message; and

transmitting from the multicarrier transceiver the repeated DMT symbols with the modulated at least one CRC bit of the CRC for the second message.

2. The method of claim 1, wherein the repetition rate is based on impulse noise levels.

3. The method of claim 1, wherein the repetition rate is based on crosstalk levels.

4. A multicarrier transceiver comprising:

a receiver that receives over a connected communications channel a first message another multicarrier transceiver indicating a repetition rate for DMT symbols;

a modulation module that modulates at least one bit of a second message onto at least one DMT symbol;

a CRC module that determines a CRC (Cyclic Redundancy Checksum) for the second message;

the modulation module further modulating at least one CRC bit of the CRC for the second message onto the at least DMT symbol;

a DMT symbol repetition module that cooperates with the modulation module and repeats the at least one DMT symbol with the modulated at least one CRC bit of the CRC for the second message according to the repetition rate indicated in the first message; and

a transmitter that transmits the repeated DMT symbols with the modulated at least one CRC bit of the CRC for the second message.

5. The transceiver of claim 4, wherein the repetition rate is based on impulse noise levels.

6. The transceiver of claim 4, wherein the repetition rate is based on crosstalk levels.

7. A multicarrier transceiver comprising:

means for receiving at the multicarrier transceiver from another multicarrier transceiver over a connected communications channel a first message indicating a repetition rate for DMT symbols;

means for modulating at least one bit of a second message onto at least one DMT symbol;

means for determining a CRC (Cyclic Redundancy Checksum) for the second message;

means for modulating at least one CRC bit of the CRC for the second message onto at the least one DMT symbol;

means for repeating the at least one DMT symbol with the modulated at least one CRC bit of the CRC for the second message according to the repetition rate indicated in the first message; and

means for transmitting from the multicarrier transceiver the repeated DMT symbols with the modulated at least one CRC bit of the CRC for the second message.

8. The transceiver of claim 7, wherein the repetition rate is based on impulse noise levels.

9. The transceiver of claim 7, wherein the repetition rate is based on crosstalk levels.

10. A non-transitory computer readable information storage media having stored thereon instructions, that when executed by a multicarrier transceiver, cause the multicarrier transceiver to:

receive at the multicarrier transceiver from another multicarrier transceiver over a connected communications channel a first message indicating a repetition rate for DMT symbols;

modulate at least one bit of a second message onto at least one DMT symbol;

determine a CRC (Cyclic Redundancy Checksum) for the second message;

modulate at least one CRC bit of the CRC for the second message onto at the least one DMT symbol;

repeat the at least one DMT symbol with the modulated at least one CRC bit of the CRC for the second message according to the repetition rate indicated in the first message; and

transmit from the multicarrier transceiver the repeated DMT symbols with the modulated at least one CRC bit of the CRC for the second message.

11. The media of claim 10, wherein the repetition rate is based on impulse noise levels.

12. The media of claim 10, wherein the repetition rate is based on crosstalk levels.