Line synchronization method in OSD system, system, and vectoring control entity

Patent metadata

Field	Value
Publication number	US-10615845-B2
Application number	US-201816125301-A
Country	US
Kind code	B2
Filing date	Sep 7, 2018
Priority date	Feb 27, 2014
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A line synchronization method in an overlapped spectrum duplex (OSD) system having K pairs of communications lines. Each pair of communications lines includes an uplink and a downlink. The method includes synchronizing downstream synchronization symbols of downlinks in the pairs of communications lines, and separately synchronizing an upstream synchronization symbol of an uplink of each pair of communications lines with a downstream synchronization symbol of a downlink of each pair of communications lines. The method may be applied to crosstalk channel estimation to distinguish near-end crosstalk (NEXT) and far-end crosstalk (FEXT) crosstalk channels when upstream and downstream spectrums are overlapped.

First claim

What is claimed is:

1. A line synchronization method comprising:
synchronizing a plurality of downstream synchronization symbols from local transceivers, in a plurality of pairs of communications lines, at least in part by configuring a plurality of local transceivers in a vectoring group to cause the downstream synchronization symbols to be at a same position, wherein each of local transceivers corresponds to one of a plurality of downlinks in an overlapped spectrum duplex (OSD) system; and
synchronizing upstream synchronization symbols with the downstream synchronization symbols at least in part by configuring a plurality of remote transceivers in the vectoring group to cause upstream synchronization symbols from the remote transceivers and the downstream synchronization symbols to be at the same position, wherein each of the remote transceivers corresponds to one of a plurality of uplinks in the OSD system.

2. The method of claim 1 , wherein configuring the remote transceivers in the vectoring group comprises directing each local transceiver to send a synchronization request to a corresponding remote transceiver, and wherein the synchronization request comprises a downstream synchronization symbol count.

3. The method of claim 1 , further comprising sending a symbol quantity offset between the upstream synchronization symbols and the downstream synchronization symbols in the pairs of communications lines to the remote transceivers.

4. The method of claim 1 , further comprising:
generating 2K orthogonal pilot sequences, wherein K is a positive integer;
allocating K of the 2K orthogonal pilot sequences to K downlinks;
allocating the remaining K orthogonal pilot sequences to K uplinks; and
sending, to remote transceivers using an operation channel, the remaining K orthogonal pilot sequences allocated to the K uplinks and positions of synchronization symbols for synchronously sending the orthogonal pilot sequences.

5. A vectoring control entity applied to an overlapped spectrum duplex (OSD) system, comprising:
a memory comprising instructions; and
a processor coupled to the memory and configured to execute the instructions, which cause the processor to be configured to:
synchronize a plurality of downstream synchronization symbols, from local transceivers in a plurality of pairs of communications lines, at least in part by configuring a plurality of local transceivers in a vectoring group to cause the downstream synchronization symbols to be at a same position, wherein each of local transceivers corresponds to one of a plurality of downlinks in an overlapped spectrum duplex (OSD) system; and
synchronize upstream synchronization symbols with the downstream synchronization symbols at least in part by configuring a plurality of remote transceivers in the vectoring group to cause upstream synchronization symbols from the remote transceivers and the downstream synchronization symbols to be at the same position, wherein each of the remote transceivers corresponds to one of a plurality of uplinks in the OSD system.

6. The vectoring control entity of claim 5 , wherein the instructions further cause the processor to be configured to control each local transceiver to send a synchronization request to a corresponding remote transceiver, and wherein the synchronization request comprises a downstream synchronization symbol count.

7. The vectoring control entity of claim 5 , wherein the instructions further cause the processor to be configured to send a symbol quantity offset between the upstream synchronization symbols and the downstream synchronization symbols in the pairs of communications lines to remote transceivers.

8. The vectoring control entity of claim 5 , wherein the instructions further cause the processor to be configured to:
configure the local transceivers in the vectoring group to modulate, on any of the downstream synchronization symbols having an index, downstream pilot sequences having the index; and
configure the remote transceivers to modulate, on any of the upstream synchronization symbols having an index, upstream pilot sequences having the index.

9. A line synchronization method comprising:
transmitting, by one of a plurality of local transceivers in a vectoring group, a downstream synchronization symbol to a remote transceiver, wherein the downstream synchronization symbol transmitted at a same position as other downstream synchronization symbols from other local transceivers, and wherein each of local transceivers corresponds to one of a plurality of downlinks in an overlapped spectrum duplex (OSD) system; and
receiving an upstream synchronization symbol from the remote transceiver, wherein the upstream synchronization symbol and the downstream synchronization symbol are aligned at the same position, and wherein each of the remote transceivers corresponds to one of a plurality of uplinks in the OSD system.

10. The method of claim 9 , wherein the downstream synchronization symbol is transmitted at the same position according to a downstream synchronization symbol count.

11. The method of claim 9 , further comprising receiving a symbol quantity offset between the upstream synchronization symbol and the downstream synchronization symbol in a plurality of pairs of communications lines.

12. The method of claim 9 , further comprising modulating, on any of the downstream synchronization symbol and the other downstream synchronization symbols having an index, downstream pilot sequences having the index.

13. A line synchronization method comprising:
receiving, by a remote transceiver, a downstream synchronization symbol from one of a plurality of local transceivers in a vectoring group, wherein the downstream synchronization symbol is received from the local transceiver at a same position as other downstream synchronization symbols from other local transceivers, and wherein each of remote transceivers corresponds to one of a plurality of downlinks in an overlapped spectrum duplex (OSD) system; and
transmitting an upstream synchronization symbol to the local transceiver, wherein the upstream synchronization symbol and the downstream synchronization symbol are aliened at the same position, and wherein each of the local transceivers corresponds to one of a plurality of uplinks in the OSD system.

14. The method of claim 13 , wherein the upstream synchronization symbol is transmitted at the same position according to an upstream synchronization symbol count.

15. The method of claim 13 , further comprising receiving a symbol quantity offset between the upstream synchronization symbol and the downstream synchronization symbol in a plurality of pairs of communications lines.

16. The method of claim 13 , further comprising modulating, on the upstream synchronization symbol having an index, upstream pilot sequences having the index.

17. A transceiver, as one of a plurality of local transceivers in a vectoring group, comprising:
a memory comprising instructions; and
a processor coupled to the memory and configured to execute the instructions, which cause the processor to be configured to:
transmit a downstream synchronization symbol to a remote transceiver, wherein the downstream synchronization symbol is transmitted at a same position as other downstream synchronization symbols from other local transceivers, and wherein each of local transceivers corresponds to one of a plurality of downlinks in an overlapped spectrum duplex (OSD) system; and
receive an upstream synchronization symbol from the remote transceiver, wherein the upstream synchronization symbol and the downstre

Assignees

• Huawei Tech Co Ltd

Inventors

• Tu Jianping

Classifications

• H04B3/487 Primary

  Testing crosstalk effects · CPC title

• H04L2012/6478

  Digital subscriber line, e.g. DSL, ADSL, HDSL, XDSL, VDSL · CPC title

• H04B3/32

  Reducing cross-talk, e.g. by compensating · CPC title

• H04L1/00

  Arrangements for detecting or preventing errors in the information received {(correcting synchronisation H04L7/00)} · CPC title