WO2016101241A1

WO2016101241A1 - Signal acquiring method, device and system

Info

Publication number: WO2016101241A1
Application number: PCT/CN2014/095066
Authority: WO
Inventors: 殷慧; 周斌
Original assignee: 华为技术有限公司
Priority date: 2014-12-26
Filing date: 2014-12-26
Publication date: 2016-06-30
Also published as: CN105934892A; CN105934892B

Abstract

Provided in an embodiment of the present invention is a signal acquiring method, comprising: a first CPE acquires a signal Z from an out-band frequency band; the signal Z includes signals from original signals of M CPEs on an uplink in-band frequency-band respectively modulated in sequence and transmitted via the out-band frequency band; the first CPE restores an original transmission signal Xi on an ith CPE from an acquired signal Z according to an orthogonal characteristic between sequences. A solution of the embodiment enables a CPE side to acquire a transmission original signal of other CPEs, and enables possibility of an offset of NEXT of the CPE side, without changing a DSL system structure; and enables a random overlap of an uplink frequency band and a downlink band, improving an overall rate of DSL.

Description

Signal acquisition method, device and system

Technical field

The present invention relates to the field of data communications, and in particular to a signal acquisition method, apparatus and system.

Background technique

Digital Subscriber Line (DSL) is a high-speed data transmission technology for transmission over twisted pair lines, such as Unshielded Twist Pair (UTP). There are multiple DSL lines in the DSL system. Currently, the DSL access multiplexer (DSLAM) provides access services for multiple DSL lines. Each twisted pair is connected to a Customer Premises Equipment (CPE) at the remote end, and the other end of the twisted pair is called a Central Office (CO). The CO device is a network-side device such as a Vectoring Control Entity (VCE), a switch, or a cabinet, and may also include a distributed access point unit (DPU); the CPE device is a user equipment. , for example, a modem. The CO of multiple twisted pairs in a cable can be on one DSLAM or on multiple DSLAMs.

There are two directions to extending DSL bandwidth. One is spectrum expansion, which increases the bandwidth of the passband; the other is to improve spectrum utilization. One way to improve the spectrum utilization is to optimize the original duplex multiplexing mode, and change the original Frequency Division Duplexing (FDD) mode to the overlap of the Overlap Spectrum Duplex (OSD). the way. However, in the FDD mode originally used by the DSL technology, the uplink and downlink transmissions are frequency-divided, and the uplink and downlink spectrums do not overlap, and only the far-end crosstalk (FEXT) is affected. The OSD method also needs to consider the impact of near-end crosstalk (NEXT), as shown in Figure 1. If NEXT does not cancel, it will also seriously affect the transmission performance. However, because CPE is generally unable to communicate directly, any CPE cannot directly know the original on other CPEs. NEXT cancellation cannot be performed by transmitting a signal, that is, a reference source for which noise cannot be known.

Summary of the invention

The embodiment of the invention provides a signal acquisition method, device and system. In a system for implementing multiple CPEs, any CPE can know the original transmission signal on other CPEs.

In a first aspect, an embodiment of the present invention provides a signal acquisition method, where the method is applied to a system with M CPEs on a user side, where M≥2;

The first CPE of the M CPEs obtains the signal Z from the out-of-band frequency band; the signal Z includes the original signals of the M CPEs in the uplink in-band frequency band, respectively, after passing through the respective sequence modulation. a signal transmitted in a frequency band; wherein the original signal X _q on the first CPE is modulated by the sequence S _q , and the original transmitted signal X _i on the i-th CPE of the other M-1 CPEs is modulated by the sequence S _i , the j-th CPE The original transmitted signal X _j is modulated by the sequence S _j ; the S _q and S _i have orthogonal characteristics, and the sequences S _i and S corresponding to any two of the other M-1 CPEs respectively _j also has orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ _{j ≤} M-1;

The first CPE restores the i-th CPE from the acquired signal Z according to an orthogonal characteristic between the S _i and S _q and an orthogonal characteristic between S _i and S _j The original transmitted signal X _i .

In a first possible implementation of the first aspect, the sequences S _q , S _i and S _j are both preamble sequences.

With reference to the first aspect, or the first possible implementation manner of the first aspect, in a second possible implementation manner, the first CPE passes the original signal X _q on the uplink in-band frequency band through the sequence S _q The post-modulation transmission includes: the first CPE modulates the original signal X _q on the uplink in-band frequency band by a sequence S _q , and transmits each element in the modulated sequence by the same or approximately the same out-of-band frequency band.

In conjunction with the first aspect, the first possible implementation of the first aspect, or the second possible implementation of the first aspect, in a third possible implementation manner, the first CPE is obtained from the Restoring the original transmitted signal X _i on the i-th CPE in the signal Z includes, the first CPE according to the formula X _i =1/L*(Z _q,1 *S _i,1 +Z _q,2 * S _i,2 +...+Z _q,k *S _i,k +...+Z _q,L *S _i,L )*H _q,i ^-1 calculates X _i; wherein Z _q,k represents the first The kth component of the signal Z acquired by a CPE; S _i,k represents the preamble sequence of the ith CPE {S _i,1 ,S _i,2 ,...,S _i,k ,...,S _i,L The kth component in }, 1 ≤ k ≤ L; L represents the length of the preamble sequence of the i-th CPE, L ≥ M; H _{q, i} represents the pair connecting the ith CPE line pair i to the first CPE q transmission parameters.

In a second aspect, an embodiment of the present invention provides a signal acquiring apparatus, where the signal acquiring apparatus and the M-1 CPEs are on the user side, M≥2; the signal acquiring apparatus includes a signal sending unit 501, and the signal receiving unit 503. And signal processing unit 505;

The signal sending unit 501 is configured to transmit the original signal X _q on the uplink frequency band by the sequence S _{q and} then send the signal through the outband frequency band;

The signal receiving unit 503 is configured to acquire a signal Z from an out-of-band frequency band; the signal Z includes a signal sent by the original signal X _q after being modulated by the sequence S _q and transmitted through an out-of-band frequency band, and the M-1 CPEs The original signal on the uplink in-band frequency band passes through the respective sequence-modulated signals transmitted through the out-of-band frequency band; wherein the original transmitted signal X _i on the i-th CPE of the M-1 CPEs passes through the sequence S _i modulation, the original transmitted signal X _j on the jth CPE is modulated by a sequence S _j ; the S _q and S _i have orthogonal characteristics, and any two of the other M-1 CPEs The corresponding sequences S _i and S _j also have orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ _{j ≤} M-1;

The signal processing unit 505 is configured to restore the ith from the acquired signal Z according to an orthogonal characteristic between the S _i and S _q and an orthogonal characteristic between S _i and S _j The original transmitted signal X _i on the CPE _.

In a first possible implementation of the second aspect, the sequences S _q , S _i and S _j are both preamble sequences.

With reference to the second aspect, in a first possible implementation manner of the second aspect, in a second possible implementation manner, the signal sending unit 501 passes the original signal X _q on the uplink in-band frequency band through the sequence S _q modulated transmission comprising: an original signal X _q in the band on the band through an uplink modulation sequence S _q, the sequence of each element of the modulation are transmitted through the outer band of the same or approximately the same frequency band.

In conjunction with the second aspect, the first possible implementation of the second aspect, or the second possible implementation of the second aspect, in a third possible implementation manner, the signal processing unit 505 obtains from the Recovering the original transmitted signal X _i on the i-th CPE in the signal Z includes, according to the formula X _i =1/L*(Z _q,1 *S _i,1 +Z _q,2 *S _i,2 +...+Z _q,k *S _i,k +...+Z _q,L *S _i,L )*H _q,i ^-1 calculates X _i; where Z _q,k indicates that the signal receiving unit 503 acquires The kth component of the signal Z; S _i,k represents the preamble sequence {S _i,1 ,S _i,2 ,...,S _i,k ,...,S _i,L } of the ith CPE k components, 1 ≤ k ≤ L; L represents the length of the preamble sequence of the i-th CPE, L ≥ M; H _{q, i} represents the connection of the i-th CPE line pair i to the line pair q connected to the signal acquisition device Transmission parameters.

In a third aspect, the embodiment of the present invention provides a network system, which includes: a plurality of central office CO devices on the network side and a plurality of customer premises equipment CPE devices on the user side;

The plurality of CO devices and the plurality of CPE devices are connected in one-to-one correspondence through twisted pairs; any one of the plurality of CPE devices is the signal acquisition device described above.

In a first possible implementation manner of the third aspect, when any two of the multiple CPEs are in the same group, the signals are sent using the same or approximately the same outband frequency band; when any two CPEs are different In the group, the outband band can be multiplexed by FDD.

In conjunction with the third aspect, in a first possible implementation manner of the third aspect, in a second possible implementation manner, the multiple CO devices may be on one or more DSL access multiplexers.

By adopting the scheme described in this embodiment, the CPE side can obtain the original transmission signals of other CPEs without changing the structure of the DSL system, so that the NEXT on the CPE side is cancelled. Further, since there is no need to worry about NEXT The impact of the uplink and downlink spectrum can be arbitrarily overlapped to increase the overall rate of the DSL system.

DRAWINGS

Figure 1 is a schematic diagram of crosstalk between lines in a DSL system;

2 is a schematic flow chart of a method according to an embodiment of the present invention;

3 is a schematic flow chart of a method according to still another embodiment of the present invention;

4 is a schematic diagram of signal processing according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram of a signal acquiring apparatus according to an embodiment of the present invention; FIG.

FIG. 6 is a schematic structural diagram of a signal acquiring apparatus according to still another embodiment of the present invention; FIG.

FIG. 7 is a schematic diagram of a network system according to an embodiment of the present invention.

detailed description

The technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the drawings in the embodiments of the present invention. It is a partial embodiment of the invention, and not all of the embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative efforts are within the scope of the present invention.

In the embodiment of the present invention, for a scenario in which crosstalk occurs, and a single twisted pair does not have crosstalk, the following refers to the case where there are multiple twisted pairs, that is, when there are multiple CPEs. In addition, the solution of the embodiment of the present invention can be applied to the scenario of multiple CPEs in the current DSL system, and can be applied to other scenarios in which multiple CPEs are connected to the peer end through the twisted pair cable. In the DSL transmission mode in which the uplink and downlink spectrum overlap, the CO and the CPE use the uplink and downlink spectrum to communicate in the band. The inband band is the frequency band in which the CPE normally receives the signal transmitted by the CO and/or the band in which the CPE normally transmits the signal to the CO. In the in-band frequency band, the CPE receives the frequency band of the signal transmitted by the CO side, and may be specifically referred to as a downlink in-band frequency band. In the case where the inband band refers to a band in which the CPE transmits a signal to the CO side, it may be specifically referred to as an inband band. In the DSL system adopting the OSD mode, since the downlink inband band and the inband band are overlapped or partially overlapped, the CPE receives the pending signal in its own inband band, including not only the CO side in its own band. The downlink signal sent to the CPE in the frequency band and arriving at the victim device, and includes the near-end crosstalk signal of the other CPE to the CPE.

To offset the NEXT on the CPE side, a dedicated frequency band other than the upstream and downstream frequency bands is used to transmit signals, which is called an out-of-band frequency band. In this out-of-band band, the CPE can send and receive signals, but CO Neither signal nor signal is received. In this way, the CPE can avoid the influence of the CO side when it is in the out-of-band band method and receiving signals.

The embodiment of the present invention provides a signal acquisition method, where the method is applied to a system with M CPEs on the user side, and M≥2; as shown in FIG. 2, the method includes:

Step 201: The first CPE of the M CPEs acquires a signal Z from an out-of-band frequency band, where the signal Z includes the original signals of the M CPEs in the uplink band and respectively passed through respective sequence modulations. The signal transmitted by the out-of-band frequency band; wherein the original signal X _q on the first CPE is modulated by the sequence S _q , and the original transmitted signal X _i on the i-th CPE of the other M-1 CPEs is modulated by the sequence S _i , The original transmitted signal X _j on the j CPEs is modulated by the sequence S _j ; the S _q and S _i have orthogonal characteristics, and the sequence S corresponding to any two of the other M-1 CPEs respectively Between _i and S _j also have orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ _{j ≤} M-1;

Here, the first CPE is actually marked as CPE q; and its corresponding original signal and sequence are marked with the subscript q, and any one of the other M-1 CPEs is marked as CPE i, and its corresponding original signal and The sequences are all labeled with the subscript i for ease of description below.

Step 203: The first CPE restores the ithth from the acquired signal Z according to an orthogonal characteristic between the S _i and S _q and an orthogonal characteristic between S _i and S _j The original transmitted signal X _i on the CPE.

Further, the sequences S _q , S _i and S _j are both a preamble sequence (P i l ot Sequence);

Specifically, for M CPEs (including the first CPE and other M-1 CPEs described above), M orthogonal preamble sequences are used, S={S ₁ , S ₂ , . . . , S _i , . . . , S _M }, Wherein S _i is a preamble sequence allocated to the i-th CPE, wherein the preamble sequence is an orthogonal pilot sequence, and any two different sequences have orthogonal characteristics, that is, an inner product of S _i and S _j is 0, (wherein I≠j), abbreviated as

The length of each sequence S _i is usually an exponential power of 2, denoted by L. One method of generating orthogonal preamble sequences is to use a Walsh Matrix, which has orthogonality between any two lines of the matrix.

Further, the first CPE recovers the original transmit signal X _i on the i-th CPE from the acquired signal Z, and the first CPE is according to the formula X _i =1/L*(Z _{q ,1} *S _i,1 +Z _q,2 *S _i,2 +... +Z _q,k *S _i,k +...+Z _q,L *S _i,L )*H _q,i ^-1 X _i; where Z _q,k represents the kth component of the signal Z acquired by the first CPE; S _i,k represents the preamble sequence {S _i,1 ,S _{i,2 of} the ith CPE ..., the _i- th component of S _i,k ,...,S _i,L }, 1≤k≤L; L represents the length of the preamble sequence of the i-th CPE, L≥M; H _q,i represents the connection i The transmission parameters of the CPE line pair i to the line pair q connecting the first CPE.

Further, the length L of the preamble sequence of the ith CPE is generally 2 ^x , and

Further, the sending, by the first CPE, the original signal X _q in the uplink inband frequency band after being modulated by the sequence S _q includes: the first CPE passes the original signal X _q on the uplink inband band through the sequence S _q Modulation, each element in the modulated sequence is transmitted through the same or approximately the same out-of-band frequency band.

A further embodiment of the present invention provides a signal acquisition method. For the sake of simplicity, the method uses four CPE scenarios as an example. However, it should be clarified that the method is not limited to the scenario where the number of CPEs is four, as long as it is The same scenario applies to multiple CPEs. As shown in FIG. 3, the method includes:

Step 301: The four CPEs transmit the original signal to be transmitted in the uplink inband to the preamble sequence, and then send the preamble sequence carrying the original signal through the outband band.

CPEs 1 to 4 in the system are respectively assigned a preamble sequence, as shown in Fig. 4, in which the preamble sequence of CPE1 is marked as S ₁ ={S _1,1 , S _1,2 , S _1,3 , S _1,4 }, the preamble sequence of CPE2 is S ₂ ={S _2,1 , S _2,2 , S _2,3 , S _2,4 }; the preamble sequence of CPE3 is S ₃ ={S _3,1 ,S _3,2 , S _3,3 , S _3,4 }; the preamble sequence of CPE4 is S ₄ ={S _4,1 , S _4,2 , S _4,3 , S _4,4 }; wherein, S ₁ , S ₂ , S ₃ and S ₄ are orthogonal to each other;

The CPEs 1 to 4 respectively transmit the original signals X ₁ , X ₂ , X ₃ and X ₄ in the uplink in-band frequency band through respective sequences, and then transmit them through the four out-of-band frequency bands. The specific processing is described as follows.

The transmission channels on M twisted pairs in a DSL system are generally marked as H, where

Any element h _ij in the matrix is a transmission parameter representing line pair j to line pair i. The crosstalk channel transmission matrix of the out-of-band channel on the four twisted pairs on which CPEs 1 to 4 are located may also be expressed as

Then, CPE1 modulates the original signal X ₁ to be transmitted in the uplink inband frequency band f ₀ with the preamble sequence S ₁ ={S _1,1 , S _1,2 , S _1,3 , S _1,4 }, and then respectively The out-of-band transmit signal Y ₁ =X ₁ *S ₁ is obtained on the frequency bands f ₁ , f ₂ , f ₃ , f ₄ , ie {Y _1,1 , Y _1,2 , Y _1,3 , Y _1,4 } ={X ₁ *S _1,1 ,X ₁ *S _1,2 ,X ₁ *S _1,3 ,X ₁ *S _1,4 }; similarly,

CPE2 modulates the original signal X ₂ to be transmitted on the uplink inband frequency band f ₀ with the preamble sequence S ₂ ={S _2,1 , S _2,2 , S _2,3 , S _2,4 }, and then respectively in the frequency band Sending on f ₁ , f ₂ , f ₃ , f ₄ ; where Y ₂ = X ₂ * S ₂ , ie {Y _2,1 , Y _2,2 , Y _2,3 , Y _2,4 }={ X ₂ *S _2,1 ,X ₂ *S _2,2 ,X ₂ *S _2,3 ,X ₂ *S _2,4 };

CPE3 modulates the original signal X ₃ to be transmitted in the uplink inband frequency band f ₀ with the preamble sequence S ₃ ={S _3,1 , S _3,2 , S _3,3 , S _3,4 }, and then respectively in the frequency band Sending on f ₁ , f ₂ , f ₃ , f ₄ ; where Y ₃ = X ₃ * S ₃ , ie {Y _3,1 , Y _3,2 , Y _3,3 , Y _3,4 }={ X ₃ *S _3,1 ,X ₃ *S _3,2 ,X ₃ *S _3,3 ,X ₃ *S _3,4 };

CPE4 modulates the original signal X ₄ to be transmitted in the uplink inband frequency band f ₀ with the preamble sequence S ₄ ={S _4,1 , S _4,2 , S _4,3 , S _4,4 }, and then respectively in the frequency band Sending on f ₁ , f ₂ , f ₃ , f ₄ ; where Y ₄ = X ₄ * S ₄ , ie {Y _4,1 , Y _4,2 , Y _4,3 , Y _4,4 }={ X ₄ *S _4,1 , X ₄ *S _4,2 , X ₄ *S _4,3 , X ₄ *S _4,4 }.

Step 303: The CPE obtains, in the out-of-band frequency band, a sum of signals modulated by the respective preamble sequences sent by all CPEs;

Specifically, CPE1 receives signals on out-of-band frequency bands f ₁ , f ₂ , f ₃ , f ₄ , labeled Z ₁ ={Z _1,1 , Z _1,2 , Z _1,3 , Z _1,4 }, Where Z _1,i (i=1,2,3,4) contains the sum of the theoretical received signals transmitted from CPE 1 to 4 to the CPE 1 in the out-of-band band (ie

), and the sum of the out-of-band noise N _i can be expressed as

Similarly, CPE2 receives signals outside the band Z ₂ = {Z _2,1 , Z _2,2 , Z _2,3 , Z _2,4 }, where

CPE3 receives the signal Z ₃ = {Z _3,1 , Z _3,2 , Z _3,3 , Z _3,4 } on the out-of-band, wherein

CPE4 receives the signal Z ₄ = {Z _4,1 , Z _4,2 , Z _4,3 , Z _4,4 } on the out-of-band, where

(among them

Represents the transpose of the jth row of matrix H).

Step 305: Any CPE restores the original signals of the other CPEs from the received signals according to the characteristics of the preamble sequence.

For any one of the CPEs _{1 to} ₄ , after receiving the signals on the frequency bands f ₁ , f ₂ , f ₃ , and f ₄ , the transmission signals of other CPEs in the frequency band can be correctly restored. The following takes CPE1 to restore the original signal X _{2 of} CPE2 on f ₀ as an example. The process is as follows:

1) Multiplying the received signal Z ₁ ={Z _1,1 , Z _1,2 , Z _1,3 , Z _1,4 } of CPE1 by the preamble sequence S _{2 of} CPE2 to obtain Z _1,1 *S _{2, 1} , Z _1,2 *S _2,2 , Z _1,3 *S _2,3 , Z _1,4 *S _2,4 .

2) Bring Z _1,i into and expand it to get:

Z _1,1 *S ₂ , ₁ =Y _1,1 *H _1,1 *S ₂ , ₁ +Y _2,1 *H _1,2 *S ₂ , ₁ +Y _3,1 *H _1,3 * S ₂ , ₁ +Y _4,1 *H _1,4 *S ₂ , ₁ +N ₁ *S ₂ , ₁

Z _1,2 *S ₂ , ₂ =Y _1,2 *H _1,1 *S ₂ , ₂ +Y _2,2 *H _1,2 *S ₂ , ₂ +Y _3,2 *H _1,3 * S ₂ , ₂ +Y _4,2 *H _1,4 *S ₂ , ₂ +N ₂ *S ₂ , ₂

Z _1,3 *S ₂ , ₃ =Y _1,3 *H _1,1 *S ₂ , ₃ +Y _2,3 *H _1,2 *S ₂ , ₃ +Y _3,3 *H _1,3 * S ₂ , ₃ +Y _4,3 *H _1,4 *S ₂ , ₃ +N ₃ *S ₂ , ₃

Z _1,4 *S ₂ , ₄ =Y _1,4 *H _1,1 *S ₂ , ₄ +Y _2,4 *H _1,2 *S ₂ , ₄ +Y _3,4 *H _1,3 * S ₂ , ₄ +Y _4,4 *H _1,4 *S ₂ , ₄ +N ₄ *S ₂ , ₄

3) Add the above four equations respectively, and according to the orthogonality of the preamble sequence, the components of Y ₁ , Y ₃ and Y ₄ are all canceled out, and finally get: Z _1,1 *S _2,1 +Z _1,2 *S _2,2 +Z _1,3 *S _2,3 +Z _1,4 *S _2,4 =4*H _1,2 *X ₂ +N'.

Specifically, the above four equations are added separately, and the left side of the equation is:

Z _1,1 *S _2,1 +Z _1,2 *S _2,2 +Z _1,3 *S _2,3 +Z _1,4 *S _2,4

The right side of the equation is:

(Y _1,1 *H _1,1 *S _2,1 +Y _1,2 *H _1,1 *S _2,2 +Y _1,3 *H _1,1 *S _2,3 +Y _1,4 *H _1,1 *S _2,4 )+(Y _2,1 *H _1,2 *S _2,1 +Y _2,2 *H _1,2 *S _2,2 +Y _2,3 *H _{1 , 2} *S _2,3 +Y _2,4 *H _1,2 *S _2,4 )+(Y _3,1 *H _1,3 *S _2,1 +Y _3,2 *H _1,3 * S _2,2 +Y _3,3 *H _1,3 *S _2,3 +Y _3,4 *H _1,3 *S _2,4 )+(Y _4,1 *H _1,4 *S _{2, 1} +Y _4,2 *H _1,4 *S _2,2 +Y _4,3 *H _1,4 *S _2,3 +Y _4,4 *H _1,4 *S _2,4 )+(N ₁ *S _2,1 +N ₂ *S _2,2 +N ₃ *S _2,3 +N ₄ *S _2,4 )=H _1,1 *(Y _1,1 *S _2,1 +Y _{1 , 2} *S _2,2 +Y _1,3 *S _2,3 +Y _1,4 *S _2,4 )+H _1,2 *(Y _2,1 *S _2,1 +Y _2,2 * S _2,2 +Y _2,3 *S _2,3 +Y _2,4 *S _2,4 ) +H _1,3 *(Y _3,1 *S _2,1 +Y _3,2 *S _{2, 2} +Y _3,3 *S _2,3 +Y _3,4 *S _2,4 )+H _1,4 *(Y _4,1 *S _2,1 +Y _4,2 *S _2,2 +Y _4,3 *S _2,3 +Y _4,4 *S _2,4 )+(N ₁ *S _2,1 +N ₂ *S _2,2 +N ₃ *S _2,3 +N ₄ *S _{2 , 4} )

N ₁ *S _2,1 +N ₂ *S _2,2 +N ₃ *S _2,3 +N ₄ *S _{2,4 is} abbreviated as N', and Y ₁ , Y ₂ , Y ₃ , Y _{4 are} substituted The above formula has:

According to the orthogonality of the preamble sequence, ie any two different preamble sequences

The inner product of any one of the preamble sequences and its own is equal to the length of the preamble sequence, and the above equation contains

with

Items are eliminated, and

The right side of the above equation is transformed into: 4*H _1,2 *X ₂ +N'; the left and right sides of the equation are transformed to obtain X ₂ +N'/4*H _1,2 ^-1 =1/4 *(Z _1,1 *S _2,1 +Z _1,2 *S _2,2 +Z _1,3 *S _2,3 +Z _1,4 *S _2,4 )*H _1,2 ^-1 .

4) Since N _i is not related to the preamble sequence, N'/4 can be approximated as the average of out-of-band noise, much smaller than the original out-of-band noise N, which can be approximated as X ₂ =1/4*(Z _1,1 * S _2,1 +Z _1,2 *S _2,2 +Z _1,3 *S _2,3 +Z _1,4 *S _2,4 )*H _1,2 ^-1 ; and H _1,2 can pass Obtained in advance by training, Z _{1,i is} available, S _{2,i is} known, (i=1,2,3,4); then passes X ₂ =1/4*(Z _1,1 *S _2,1 +Z _1,2 *S _2,2 +Z _1,3 *S _2,3 +Z _1,4 *S _2,4 )*H _1,2 ^-1 can calculate X ₂ .

Similarly, to restore the original signal X ₃ (or X ₄ ) of CPE3 (or CPE4) on CPE1, it is only necessary to receive the signal of CPE1 Z ₁ = {Z _1,1 in step 1) of the above calculation process. Z _1,2 , Z _1,3 , Z _1,4 } are multiplied by the preamble sequence S ₃ (or S ₄ ) of CPE3 (or CPE4), respectively, and then obtained by stepwise calculation according to the above procedure. To restore the original signals on CPE1, CPE3, and CPE4 on CPE2, multiply the CPE1 by the received signal Z ₂ = {Z _2,1 , Z _2,2 , Z _2,3 , Z _2,4 } of CPE2, respectively. The preamble sequences S ₁ , S ₃ and S _{4 of} CPE3 and CPE4 can be calculated according to the above process; the original signals on other CPEs are similarly reduced on CPE3 or CPE4, and will not be described again. Expanded, in M CPEs, M≥2, the qth CPE needs to obtain the original transmitted signal X _i on the i-th CPE according to the formula X _i =1/L*(Z _q,1 *S _{i, 1} +Z _q,2 *S _i,2 +...+Z _q,k *S _i,k +...+Z _q,L *S _i,L )*H _q,i ^{-1 is} calculated _, where Z _{q, k} represents the kth component of the signal Z acquired by the qth CPE, 1≤k≤L; S _i,k represents the preamble sequence of the ith CPE {S _i,1 ,S _i,2 ,... , the kth component in S _i,k , . . . , S _i,L }; L represents the length of the preamble sequence of the i-th CPE, L≥M; H _q,i represents the M corresponding to the M CPEs The transmission parameter of line pair i to line pair q in the pair of lines.

It should be noted that, from the above step 4), the calculated X ₂ is an approximation. In fact, the approximation includes the out-of-band noise N'/4; although the obtained X ₂ is not absolutely accurate, it is different from the true value. Very small, as a reference signal to eliminate near-end crosstalk can basically achieve the purpose.

Through the method of the above embodiment, any CPE can recover the original signals of other CPEs from its own received signal, as the CPE cancels the reference signal of the in-band NEXT crosstalk from other CPEs, so that the offset NEXT crosstalk becomes may.

It should be noted that, in the above solution, four CPEs need to use the same outband frequency band to transmit signals, because the scheme is applicable to other numbers of CPEs (at least two or more) scenarios; when the number of CPEs is large The CPEs may be grouped first, and the CPEs in the same group use the same or approximately the same outband frequency band to transmit signals; the CPEs in different groups may use the FDD method to multiplex the outband frequency bands, so that the CPE between the groups and the groups The out-of-band bands of the transmitted signals do not overlap, and the CPEs in each group and the CPEs in each group are processed as described above.

For example, suppose CPE1 belongs to group 1, CPE2 belongs to group 2, group 1 uses Band1 to send signals, group 2 uses Band2 to send signals, and Band1 and Band2 spectrums do not overlap. If CPE1 wants to restore the original transmission signal of CPE2, it is only for CPE1 on Band2. The received signal can be processed as described above.

The embodiment of the present invention further provides a signal acquisition device 500, wherein the signal acquisition device 500 and the M-1 CPEs are on the user side, M≥2; as shown in FIG. 5, the signal acquisition device 500 includes a signal transmission unit. 501, signal receiving unit 503, signal processing unit 505;

The signal sending unit 501 is configured to send the original signal X _q in the uplink band to the sequence S _{q and} then send the signal;

Further, the sequences S _q , S _i and S _j are both preamble sequences;

Further, the signal processing unit 505 restores the original transmit signal X _i on the i-th CPE from the acquired signal Z, according to the formula X _i =1/L*(Z _q,1 *S _i,1 +Z _q,2 *S _i,2 +...+Z _q,k *S _i,k +...+Z _q,L *S _i,L )*H _q,i ^-1 calculates X _i; Where Z _q,k represents the kth component of the signal Z acquired by the signal receiving unit 503; S _i,k represents the preamble sequence of the ith CPE {S _i,1 ,S _i,2 ,...,S _{i, k} , ..., S _{i, L} } the kth component, 1 ≤ k ≤ L; L represents the length of the preamble sequence of the i-th CPE, L ≥ M; H _{q, i} represents the connection of the i-th CPE line The transmission parameter of i to the line pair q connecting the signal acquisition means.

Further, the signal transmitting unit 501 on the original signal X _q S _q band after the modulated transmission sequence included within the uplink band: the original signal X _q S _q serialized band modulation in the uplink band, the modulation Each element in the subsequent S _q sequence is transmitted by the same or approximately the same out-of-band frequency band.

The specific processing actions in the signal sending unit 501, the signal receiving unit 503, and the signal processing unit 505 are consistent with the manners and processes in the foregoing method embodiments, and details are not described herein again.

Further, the signal acquisition device is a CPE or part of a CPE.

The embodiment of the present invention further provides a signal acquisition device 600. The signal acquisition device 600 and the M-1 CPEs are on the user side, and M≥2. As shown in FIG. 6, the device in this embodiment may include: a receiver. 601, a receiver 603 and a processor 605;

The transmitter 601 is configured to send, after the original signal X _q in the uplink band, is modulated by the sequence S _q ;

The receiver 603 is configured to obtain a signal frequency band from Z; Z signal comprising the signal of the original signal after the sequence X _q S _q is modulated by the transmission frequency band, and the CPE in the M-1 The original signal on the uplink in-band frequency band passes through the respective sequence-modulated signals transmitted through the out-of-band frequency band; wherein the original transmitted signal X _i on the i-th CPE of the M-1 CPEs passes through the sequence S _i modulation, the original transmitted signal X _j on the jth CPE is modulated by a sequence S _j ; the S _q and S _i have orthogonal characteristics, and any two of the other M-1 CPEs respectively Corresponding sequences S _i and S _j also have orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ _{j ≤} M-1;

The processor 605 is configured to restore the i th from the acquired signal Z according to an orthogonal characteristic between the S _i and S _q and an orthogonal characteristic between S _i and S _j The original transmitted signal X _i on the CPE _.

The device in this embodiment may be used to implement the technical solution of the method embodiment shown in FIG. 2 or FIG. 3, and the implementation principle and technical effects are similar, and details are not described herein again.

The embodiment of the present invention further provides a network system. As shown in FIG. 7, the system in this embodiment includes: multiple CO devices on the network side and multiple CPE devices on the user side; the multiple CO devices and devices The plurality of CPE devices are connected in a one-to-one correspondence through a twisted pair; any one of the plurality of CPE devices may adopt the structure of the device embodiment shown in FIG. 5 or FIG. 6, which correspondingly can be executed in FIG. 2 or FIG. The technical solution of the method embodiment has similar implementation principles and technical effects, and details are not described herein again.

In the foregoing solution, when any two CPEs in multiple CPEs are in the same group, signals are transmitted using the same or approximately the same outband frequency band; when any two CPEs are in different groups, the outband band may be multiplexed by using FDD mode; Such that the out-of-band bands of the CPE transmission signals between the groups and the groups do not overlap, The CPEs in each group and the CPEs in each group were treated as described above.

The COs on the plurality of twisted pairs shown in FIG. 7 may be on one DSLAM or may be distributed on multiple DSLAMs.

In the several embodiments provided by the present invention, it should be understood that the disclosed apparatus and method may be implemented in other manners. For example, the device embodiments described above are merely illustrative. For example, the division of the unit is only a logical function division. In actual implementation, there may be another division manner, for example, multiple units or components may be combined or Can be integrated into another system, or some features can be ignored or not executed. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be an indirect coupling or communication connection through some interface, device or unit, and may be in an electrical, mechanical or other form.

The units described as separate components may or may not be physically separated, and the components displayed as the unit may or may not be physical units, that is, may be located in one place, or may be distributed to multiple network units. . Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above integrated unit can be implemented in the form of hardware or in the form of hardware plus software functional units.

The above-described integrated unit implemented in the form of a software functional unit can be stored in a computer readable storage medium. The above software functional unit is stored in a storage medium and includes instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) or a processor to perform the methods of the various embodiments of the present invention. Part of the steps. The foregoing storage medium includes: a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disk, and the like, which can store program codes. .

Those skilled in the art will clearly understand that for the convenience and brevity of the description, only the above The division of the function modules is exemplified. In practical applications, the above function assignments may be completed by different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. For the specific working process of the device described above, refer to the corresponding process in the foregoing method embodiment, and details are not described herein again.

Finally, it should be noted that the above embodiments are merely illustrative of the technical solutions of the present invention, and are not intended to be limiting; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art will understand that The technical solutions described in the foregoing embodiments may be modified, or some or all of the technical features may be equivalently replaced; and the modifications or substitutions do not deviate from the technical solutions of the embodiments of the present invention. range.

Claims

A signal acquisition method, the method being applied to a system having M CPEs on a user side, M≥2; wherein the method comprises

The first CPE of the M CPEs obtains the signal Z from the out-of-band frequency band; the signal Z includes the original signals of the M CPEs in the uplink in-band frequency band, respectively, after passing through the respective sequence modulation. a signal transmitted in a frequency band; wherein the original signal X q on the first CPE is modulated by the sequence S q , and the original transmitted signal X i on the i-th CPE of the other M-1 CPEs is modulated by the sequence S i , the j-th CPE The original transmitted signal X j is modulated by the sequence S j ; the S q and S i have orthogonal characteristics, and the sequences S i and S corresponding to any two of the other M-1 CPEs respectively j also has orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ j ≤ M-1;

The first CPE restores the i-th CPE from the acquired signal Z according to an orthogonal characteristic between the S i and S q and an orthogonal characteristic between S i and S j The original transmitted signal X i .
The method of claim 1 wherein said sequences S q , S i and S j are both preamble sequences.
The method according to claim 1 or 2, wherein the transmitting, by the first CPE, the original signal X q on the uplink in-band frequency band after being modulated by the sequence S q comprises:

The first CPE the original signal X q frequency bands within the uplink band through S q modulation, the modulated sequence elements respectively through the outer band transmission with identical or nearly identical.
The method according to claim 1, 2 or 3, wherein the first CPE restores the original transmitted signal X i on the i-th CPE from the acquired signal Z, the A CPE according to the formula X i =1/L*(Z q,1 *S i,1 +Z q,2 *S i,2 +...+Z q,k *S i,k +...+Z q,L *S i,L )*H q,i -1 calculates X i ; where Z q,k represents the kth component of the signal Z acquired by the first CPE; S i,k represents the ith CPE The k-th component of the preamble sequence {S i,1 ,S i,2 ,...,S i,k ,...,S i,L }, 1≤k≤L; L represents the preamble sequence of the i-th CPE The length, L ≥ M; H q, i represents the transmission parameter connecting the i-th CPE line pair i to the line pair q connecting the first CPE.
A signal acquisition device, the signal acquisition device and the M-1 CPEs are on the user side, M≥2, characterized in that the signal acquisition means comprises a signal transmitting unit 501, a signal receiving unit 503 and a signal processing unit 505;

The signal sending unit 501 is configured to transmit the original signal X q on the uplink frequency band by the sequence S q and then send the signal through the outband frequency band;

The signal receiving unit 503 is configured to acquire a signal Z from an out-of-band frequency band; the signal Z includes a signal sent by the original signal X q after being modulated by the sequence S q and transmitted through an out-of-band frequency band, and the M-1 CPEs The original signal on the uplink in-band frequency band passes through the respective sequence-modulated signals transmitted through the out-of-band frequency band; wherein the original transmitted signal X i on the i-th CPE of the M-1 CPEs passes through the sequence S i modulation, the original transmitted signal X j on the jth CPE is modulated by a sequence S j ; the S q and S i have orthogonal characteristics, and any two of the other M-1 CPEs The corresponding sequences S i and S j also have orthogonal characteristics; wherein 1 ≤ i ≤ M-1, 1 ≤ j ≤ M-1;

The signal processing unit 505 is configured to restore the ith from the acquired signal Z according to an orthogonal characteristic between the S i and S q and an orthogonal characteristic between S i and S j The original transmitted signal X i on the CPE .
The signal acquisition apparatus according to claim 5, wherein said sequences S q , S i and S j are both preamble sequences;
The signal obtaining apparatus according to claim 5 or 6, wherein the signal transmitting unit 501 transmits the original signal X q in the uplink band to the sequence S q and then transmits: The original signal X q is modulated by the sequence S q , and each element in the modulated sequence is transmitted through the same or approximately the same out-of-band frequency band.
The signal acquisition apparatus according to claim 5, 6 or 7, wherein the signal processing unit 505 restores the original transmission signal X i on the i-th CPE from the acquired signal Z, According to the formula X i =1/L*(Z q,1 *S i,1 +Z q,2 *S i,2 +...+Z q,k *S i,k +...+Z q,L *S i, L ) * H q, i -1 calculates X i; wherein Z q,k represents the kth component of the signal Z acquired by the signal receiving unit 503; S i,k represents the i-th CPE The kth component of the preamble sequence {S i,1 ,S i,2 ,..., S i,k ,...,S i,L }, 1≤k≤L; L represents the length of the preamble sequence of the i-th CPE , L ≥ M; H q, i represents a transmission parameter connecting the i-th CPE line pair i to the line pair q connected to the signal acquisition device.
A network system, comprising: a plurality of central office CO devices on the network side and a plurality of customer premises equipment CPE devices on the user side;

The plurality of CO devices and the plurality of CPE devices are connected in one-to-one correspondence by twisted pairs; and any one of the plurality of CPE devices is the signal acquiring device according to any one of claims 5 to 8.
The network system according to claim 9, wherein when any two of the plurality of CPEs are in the same group, signals are transmitted using the same or approximately the same outband frequency band; when any two CPEs are different In the group, the outband band can be multiplexed by FDD.
A network system according to claim 9 or 10, wherein said plurality of CO devices are on one or more DSL access multiplexers.