WO2012149791A1 - 一种串扰信道估计方法、装置及系统 - Google Patents

一种串扰信道估计方法、装置及系统 Download PDF

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Publication number
WO2012149791A1
WO2012149791A1 PCT/CN2011/080472 CN2011080472W WO2012149791A1 WO 2012149791 A1 WO2012149791 A1 WO 2012149791A1 CN 2011080472 W CN2011080472 W CN 2011080472W WO 2012149791 A1 WO2012149791 A1 WO 2012149791A1
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WIPO (PCT)
Prior art keywords
pilot sequence
line
uplink
pilot
sequence
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PCT/CN2011/080472
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English (en)
French (fr)
Inventor
刘立贺
曹用武
王祥
吕捷
Original Assignee
华为技术有限公司
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Publication date
Application filed by 华为技术有限公司 filed Critical 华为技术有限公司
Priority to PCT/CN2011/080472 priority Critical patent/WO2012149791A1/zh
Priority to CN201180001781.0A priority patent/CN102388588B/zh
Publication of WO2012149791A1 publication Critical patent/WO2012149791A1/zh

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04B—TRANSMISSION
    • H04B3/00—Line transmission systems
    • H04B3/02—Details
    • H04B3/32—Reducing cross-talk, e.g. by compensating
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/22—Arrangements for supervision, monitoring or testing
    • H04M3/26—Arrangements for supervision, monitoring or testing with means for applying test signals or for measuring
    • H04M3/34—Testing for cross-talk
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/0202—Channel estimation
    • H04L25/0204—Channel estimation of multiple channels
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00—Baseband systems
    • H04L25/02—Details ; arrangements for supplying electrical power along data transmission lines
    • H04L25/0202—Channel estimation
    • H04L25/0224—Channel estimation using sounding signals

Definitions

  • the present invention relates to the field of communications technologies, and in particular, to a crosstalk channel estimation method, apparatus, and system.
  • xDSL Digital Subscriber Line
  • DSL Digital Subscriber Line
  • UTP Unshielded Twist Pair
  • DSL. Access Multiplexer Due to the principle of electromagnetic induction, multiple signals transmitted by the DSLAM will interfere with each other, called crosstalk, such as near-end crosstalk (NEXT) and far-end crosstalk (FEXT), where near-end crosstalk (NEXT) is applied to the system. Performance does not cause too much harm, and because the frequency band used by xDSL is wider and wider, far-end crosstalk (FEXT) will seriously affect the transmission performance of the line.
  • Far-end crosstalk FXT is shown in Figure 1.
  • Vectored-DSL technology which mainly uses the possibility of joint transmission and reception at the DSLAM end, and uses signal processing methods to cancel the interference of FEXT.
  • a vector precoding is introduced at the DSLAM end.
  • the unit P performs joint transmission of signals and receives them at the user end.
  • a crosstalk canceller W is introduced at the DSLAM end to perform joint reception processing of signals to cancel crosstalk.
  • Il P may be referred to as a crosstalk channel estimation parameter
  • the process of obtaining a crosstalk channel estimation parameter is a process of estimating a crosstalk channel, in which each transceiver at the transmitting end modulates a pilot sequence on a Sync Symbol (Pilot) Sequence), the receiver measures the error sample caused by crosstalk on the synchronization symbol at the receiving end (Error Sample), the receiver passes the error sample to the VCE (Vectoring Control Entity), and the VCE is based on the pilot sequence and the error sample.
  • the crosstalk cancellation matrix W and the vector precoding matrix P are calculated.
  • Embodiments of the present invention provide a crosstalk channel estimation method, apparatus, and system, which can shorten the time of crosstalk channel estimation.
  • a crosstalk channel estimation method for a subscriber line includes:
  • the vectoring control entity VCE generates an orthogonal training pilot sequence matrix according to the size of the subscriber line;
  • the VCE allocates a pilot sequence to each of the uplink subscriber lines i according to the orthogonal training pilot sequence matrix, and the allocated pilot sequence is modulated by the transmitting terminal Ti on each of the uplink subscriber lines i Transmitting, wherein the pilot sequences of any two of the uplink subscriber lines are orthogonal to each other; the VCE receives the error samples sent by the receiving end Ri of each of the uplink subscriber lines i, and the error samples are received by the The terminal Ri is obtained according to the modulated signal of the received pilot sequence;
  • the VCE calculates a crosstalk channel estimation parameter according to all error samples that have been received and a pilot sequence of the uplink subscriber line.
  • a crosstalk channel estimation apparatus for a subscriber line comprising:
  • a matrix generating unit configured to generate an orthogonal training pilot sequence matrix according to a size of the user line
  • a sequence allocation unit configured to respectively allocate a pilot sequence for each uplink subscriber line i according to the orthogonal training pilot sequence matrix, where the allocated pilot sequence is modulated by each of the uplink subscriber lines i
  • the transmitting end Ti sends out, where the pilot sequences of any two lines in the uplink user line are orthogonal to each other;
  • a sample receiving unit configured to receive an error sample sent by the receiving end Ri of each of the uplink subscriber lines i, where the error sample is received by the receiving end Ri according to a modulated signal of the received pilot sequence;
  • a crosstalk channel estimation system includes a VCE, a transmitting end Ti and a receiving end Ri of each uplink subscriber line i,
  • the VCE is configured to generate an orthogonal training pilot sequence matrix according to the size of the user line lady; and allocate a pilot sequence to each uplink user line i according to the orthogonal training pilot sequence matrix, where the online user
  • the pilot sequences of any two lines in the line are orthogonal to each other; the error samples sent by the receiving end Ri of each of the uplink subscriber lines i are received; according to all the received error samples and the pilot sequence of the uplink subscriber line Calculating the crosstalk channel estimation parameters;
  • the transmitting end Ti is configured to send, to the receiving end Ri, a modulation signal of a pilot sequence allocated by the VCE to an uplink subscriber line i;
  • the receiving end Ri is configured to obtain an error sample according to the modulated signal of the received pilot sequence, and send the error sample to the VCE.
  • the orthogonal training pilot sequence matrix is pre-generated by the VCE, and then the pilot sequence on the line is allocated only for the uplink user according to the matrix, and the crosstalk channel estimation parameter is finally determined according to the pilot sequence on the uplink subscriber line.
  • the method of allocating a pilot sequence to each subscriber line regardless of the line state greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the subscriber line.
  • the number of received error samples received by the VCE shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time for subscriber line activation and tracking, and improving the user experience. Moreover, the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • FIG. 1 is a schematic diagram of remote crosstalk under a multi-channel xDSL access system
  • FIG. 2a is a schematic diagram of introducing a vector precoder P for signal joint transmission at a DSLAM end
  • FIG. 2b is a schematic diagram of introducing a crosstalk canceller W for signal joint reception at a DSLAM end
  • 3 is a flowchart of a crosstalk channel estimation method according to an embodiment of the present invention
  • FIG. 4 is a schematic diagram of a process of generating an error sample in an embodiment of the present invention.
  • FIG. 5 is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • FIG. 6 is a schematic diagram of a matrix of orthogonal training pilot sequences in the embodiment shown in FIG. 5;
  • FIG. 7 is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • Figure 8a is a schematic diagram of the distribution of the line pilot sequences in the embodiment shown in Figure 7;
  • 8d-8e are schematic diagrams showing the allocation of the line pilot sequence when the uplink subscriber line is activated in the embodiment shown in FIG. 7;
  • Figure 8f is a schematic diagram of a shortened pilot sequence in the embodiment of Figure 7;
  • FIG. 9 is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • 10a is a schematic diagram of a matrix of orthogonal training pilot sequences in the embodiment shown in FIG. 9;
  • Figure 10b is a schematic diagram of the distribution of the line pilot sequences in the embodiment shown in Figure 9;
  • Figure 10c is a schematic illustration of a shortened pilot sequence in the embodiment of Figure 9;
  • Figure 10d is a schematic illustration of another shortened pilot sequence in the embodiment of Figure 9;
  • FIG. 11 is a schematic structural diagram of a crosstalk channel estimation apparatus according to an embodiment of the present invention.
  • FIG. 12 is a schematic structural diagram of another crosstalk channel estimation apparatus according to an embodiment of the present invention.
  • FIG. 13 is a schematic structural diagram of a crosstalk channel estimation system according to an embodiment of the present invention.
  • FIG. 3 it is a flowchart of a crosstalk channel estimation method according to an embodiment of the present invention.
  • the method can include:
  • Step 301 The VCE generates an orthogonal training pilot sequence matrix according to the size of the subscriber line.
  • the VCE is the control entity of the entire Vectored DSL.
  • the VCE is firstly based on the scale of the subscriber line in a system such as a vectored DSL system.
  • the orthogonal training pilot sequence matrix is generated, and when the pilot sequence on the line is allocated subsequently, the training pilot sequence matrix can be directly allocated.
  • the orthogonal training pilot sequence may be a Walsh matrix.
  • Step 302 The VCE allocates a pilot sequence for each uplink user line i according to the orthogonal training pilot sequence matrix.
  • the VCE When the user in the system is in the showtime state when the user goes online, the VCE is not the same as the prior art.
  • the pilot sequence is assigned to each subscriber line regardless of the line state, but is described in this step, but according to the above steps.
  • the orthogonal training pilot sequence matrix allocates pilot sequences on the line only for the upper line users, and the pilot sequences on the uplink user lines are orthogonal to each other.
  • the other elements in the matrix form a pilot sequence on a certain line. For details, refer to the description of the subsequent embodiments.
  • the transmitting terminal Ti on each line i can transmit a modulated signal of the pilot sequence to the opposite end, that is, the receiving terminal Ri, according to the allocated pilot sequence.
  • "i" represents a certain online subscriber line
  • Ti and Ri respectively represent the transmitting end and the receiving end of the line, which are merely convenient for presentation, and are not specific.
  • the transmitting end on each line is each user end, and the modulated signals of the pilot sequences in orthogonal relationship are transmitted to the DSLAM end; for the downlink signal, the transmitting end on each line is at the DSLAM end, Each subcarrier transmits a modulated signal of a pilot sequence that is orthogonal to each other to each user end.
  • the transmitting end Ti on each line i is modulated according to the pilot sequence allocated by the VCE to generate a modulated signal in each synchronization symbol, and then transmitted to the receiving end Ri, wherein the process of generating a modulated signal by modulating the pilot sequence, such as The constellation points on the constellation of the frequency sequence are modulated by the above description for those skilled in the art.
  • Step 303 The VCE receives an error sample sent by the receiving end Ri of each online subscriber line i. After the transmitting end Ti transmits the modulated signal of the pilot sequence, it is received by the receiving end Ri on the line i, and the far-end crosstalk is generated between different lines during the transmission of the signal on the line, so the signal received by the receiving end Ri and There may be a certain difference between the signals sent by the transmitting end Ti, and the receiving end Ri determines the signal sent by the transmitting end Ti according to the modulated signal of the received pilot sequence, and calculates and receives the signal. The difference between the signal and the transmitted signal obtains an error sample. For example, the receiving end Ri determines the constellation point transmitted by the transmitting end Ti according to the received signal, and uses the difference between the received signal and the determined constellation point as an error sample.
  • the above process can be used for the calculation of the uplink and downlink error samples.
  • the transmitting terminal Ti is the VTU-R, that is, the network management system side
  • the receiving end Ri is the VTU- 0 is the user side
  • the pilot sequence used by the VTU-R is VCE configured to VTU-0 and notified to the VTU-R by the VTU-0 through the message, so the uplink transmitted pilot sequence is for VTU-0.
  • the transmitted constellation point can also be directly used as a reference point, and the difference between the reception point and the transmission constellation point is calculated as an error sample.
  • the process of calculating the error samples by the receiving end Ri according to the received signals can be realized by those skilled in the art according to the above description.
  • the receiving end Ri sends the error sample to the VCE after calculating the error sample.
  • the transmitting end transmits the pilot sequence modulation signals xl, x2, and after receiving the pilot sequence modulation signals yl, y2, each receiver receives
  • the modulated signals xl, x2 at the transmitting end are determined according to the signals yl, y2, and the error samples 1 and the error samples 2 are respectively calculated and sent to the VCE.
  • Step 304 The VCE calculates the crosstalk channel estimation parameter according to all the error samples that have been received and the pilot sequence on the uplink subscriber line.
  • the VCE calculates the crosstalk channel estimation parameters according to the received error samples and the pilot sequences on each line, such as the crosstalk cancellation matrix W and the vector precoding matrix P. After obtaining W and P, the DALAM terminal can be determined according to the VCE. And P adjust the crosstalk canceller and the vector precoder, and the uplink and downlink joint processing is performed by the crosstalk canceller and the vector precoder to achieve the effect of eliminating far-end crosstalk.
  • the process of calculating the crosstalk channel estimation parameters such as W and P according to the error sample and the pilot sequence by the VCE is implemented by the above description according to the above description.
  • the orthogonal training pilot sequence matrix is pre-generated by the VCE, and then the pilot sequence on the line is allocated only for the uplink user according to the matrix, and the crosstalk channel estimation parameter is finally determined according to the pilot sequence on the uplink subscriber line.
  • the method of allocating a pilot sequence to each subscriber line regardless of the line state greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the subscriber line.
  • the number of received error samples received by the VCE shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time of user line activation and tracking, and improving the user experience. Moreover, the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • FIG. 5 it is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • the method can include:
  • Step 501 The VCE generates an orthogonal training pilot sequence matrix according to the size of the user line.
  • the VCE can generate a Walsh matrix of size ⁇ ⁇ , as shown in Figure 6, where M is ⁇ 1 . 82 ⁇ 1 (if the first line in the matrix is idle, not allocated and occupied) or 2 1 ° (the first row of the matrix participates in the allocation), N is
  • the rows of the matrix are numbered starting from 0, that is, the first line is 0. On the line of the online user.
  • the VCE allocates the pilot sequence on the line only for the uplink user.
  • the element of a certain row in the orthogonal training pilot sequence matrix is selected as a pilot sequence on a certain line, for example, a line is used. 2
  • the first row element in the orthogonal training pilot sequence matrix can be selected as the pilot sequence on the line.
  • the VCE sequentially allocates the lines in the orthogonal training pilot sequence matrix as a pilot sequence according to the uplink order of the online users.
  • the VCE allocates, according to the port number of the online user, the line corresponding to the port number in the orthogonal training pilot sequence matrix as a pilot sequence, and assigns it to the line of the online user corresponding to the port number, where the port number and the number of rows in the matrix --correspond.
  • pilot sequence on the line using the largest number of lines in the orthogonal training pilot sequence matrix is replaced with the smallest number of unused lines in the orthogonal training pilot sequence matrix. Pilot sequence;
  • the unused lines in the orthogonal training pilot sequence matrix are assigned as pilot sequences to the active line and are assigned to each active line.
  • the assigned pilot sequences are orthogonal between the partial columns, preferably such that the pilot sequences assigned on each active line are orthogonal between the least columns. For example, a pilot sequence with a smaller number of rows in the orthogonal training pilot sequence matrix is allocated to the active line, and a pilot sequence having the smallest number of unused lines in the orthogonal training pilot sequence matrix is used as a new one.
  • the pilot sequence is reassigned to the line that has used the smaller number of pilot sequences.
  • steps 303 and 304 above may be directly performed, or the following steps 503 to 505 may be continued.
  • Step 503 The VCE selects a part of the pilot sequence as a shortened pilot sequence on the pilot sequence of each uplink subscriber line.
  • a part of the pilot sequence may be further selected in the allocated pilot sequence to shorten the size of each pilot sequence sent by the transmitting end, and the subsequent calculation error is compressed.
  • the specific process of selecting a part of the pilot sequence may be: intercepting a continuous number of pilot sequences in each pilot sequence of the uplink subscriber line as a shortened pilot sequence; or, pilots on each uplink subscriber line A pilot sequence in which the number of columns is discontinuous is selected in the sequence as a shortened pilot sequence and the like. In short, as long as the shortened pilot sequences are orthogonal to each other.
  • the transmitting end of each uplink subscriber line can transmit the modulated signal of the shortened pilot sequence, and after receiving the modulated signal of the crosstalked pilot sequence, the receiving end receives the modulated signal of the pilot sequence.
  • the corresponding error samples are calculated and sent to the VCE.
  • Step 504 The VCE receives an error sample corresponding to the shortened pilot sequence sent by the receiving end on each uplink subscriber line.
  • the error sample calculated by the receiving end is the error sample corresponding to the shortened pilot sequence.
  • the method for calculating the error samples is similar to the corresponding description in the foregoing step 303, except that the modulated signals of the received pilot sequences are different and will not be described again here.
  • the VCE may further determine the start and end positions of the received error samples when receiving the error samples to receive shorter error samples, and to calculate the calculation process of the next step.
  • Step 505 The VCE is based on the received error sample and the shortened pilot sequence on the uplink user line.
  • the column calculation obtains the crosstalk channel estimation parameters.
  • the method for obtaining the crosstalk channel estimation parameter is similar to the foregoing step 304, except that the pilot sequence according to the calculation is different, and details are not described herein again.
  • the embodiment of the present invention further shortens the pilot sequence on each line, further reduces the period length of the pilot sequence, shortens the transmission time of the pilot sequence in one cycle range, and reduces the VCE reception.
  • the number of samples received by the error sample shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time of user line activation and tracking, and improving the user experience.
  • FIG. 7 is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • the method can include:
  • Step 701 In the VCE initialization process, generate an orthogonal training sequence matrix according to the size of the vectored DSL system.
  • the vectored DSL system is still a 24-pair line, and the VCE can generate a Walsh matrix of size ⁇ ⁇ , as shown in FIG. 6 , where M is ⁇ 1 ⁇ 1 (if in the matrix) The first line of behavior is idle, not allocated and occupied) or ⁇ 1 . 82 " , N is 24.
  • the orthogonal training sequence matrix is described by taking a 32 32 Walsh matrix as an example.
  • Step 702 The VCE sequentially allocates the rows in the orthogonal training pilot sequence matrix as pilot sequences according to the uplink sequence of the online users, and allocates them to the lines of each online user.
  • the pilot sequence on the line using the largest number of lines in the orthogonal training pilot sequence matrix is replaced with the pilot with the smallest number of unused lines in the orthogonal training pilot sequence matrix. sequence.
  • the unused lines in the orthogonal training pilot sequence matrix are assigned as pilot sequences to the active line and the pilot sequences assigned on each active line are assigned.
  • the orthogonality is satisfied on the least number of columns. For example, the row in the orthogonal training pilot sequence matrix A smaller number of pilot sequences are allocated to the active line, and the pilot sequence with the smallest number of unused lines in the orthogonal training pilot sequence matrix is reassigned as a new pilot sequence to the number of used lines. A small pilot sequence on the line.
  • lines 4, 23, 12, and 9 are showtime status lines, lines 11 and 5 are active, and lines 1 through 4 of the orthogonal training pilot sequence matrix are sequentially ordered in line activation order before lines 11 and 5 are activated.
  • the first line (line 0) is reserved, when lines 11 and 5 are active, the 1st to 2nd lines are sequentially assigned to the active lines 11 and 5, and will not
  • the 5th to 6th lines of the pilot sequence with the smallest number of lines used are redistributed as new pilot sequences to lines 4, 23 of the pilot sequence having a smaller number of lines, that is, the uppermost line of the matrix is allocated to
  • the active line replaces the pilot sequence of the existing showtime line with the pilot sequence with the smallest number of unused lines in the matrix, as shown in Figures 8d-8e.
  • Step 703 The VCE intercepts a pilot sequence of consecutive columns in the pilot sequence allocated on each uplink subscriber line as a shortened pilot sequence.
  • the maximum number of rows of pilot sequences that have been used is Z
  • the intercepted pilot sequences are between the number of columns in the orthogonal training pilot sequence from start to start+3. Each pilot sequence.
  • the transmitting end of each uplink subscriber line can transmit the modulated signal of the shortened pilot sequence, and after receiving the modulated signal of the crosstalked pilot sequence, the receiving end receives the modulated signal of the pilot sequence.
  • the corresponding error samples are calculated and sent to the VCE.
  • Step 704 the VCE receives the shortened pilot sequence pair sent by the receiving end on each uplink subscriber line.
  • the error sample should be.
  • the error sample received by the VCE is that the number of rows in the orthogonal pilot sequence shown in FIG. 6 transmitted by the receiving end is the first to fourth rows, and the number of columns is from start to start+3. Error samples obtained from the modulated signals of the pilot sequences on the four lines. After confirming that the error sample is collected, VCE performs the next step.
  • Step 705 The VCE calculates the crosstalk channel estimation parameter according to the received error sample and the shortened pilot sequence on each uplink subscriber line.
  • the embodiment of the invention greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the case that the subscriber line is not 100% fully activated, not only reduces the period length of the pilot sequence, but also shortens a period range.
  • the transmission time of the inner pilot sequence also reduces the number of received error samples received by the VCE, shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time for subscriber line activation and tracking, and improving the time. user experience.
  • the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • FIG. 9 is a flowchart of another crosstalk channel estimation method according to an embodiment of the present invention.
  • the method can include:
  • Step 901 In the VCE initialization process, generate an orthogonal training sequence matrix according to the size of the vectored DSL system.
  • orthogonal training pilot sequence shown in FIG. 6 is still taken as an example for description.
  • Step 902 The VCE allocates a line corresponding to the port number in the orthogonal training pilot sequence matrix as a pilot sequence according to the port number of the online user, and allocates the line to the line of the online user.
  • the port number corresponds to the number of rows in the matrix, as shown in Figure 10a.
  • the pilot sequences used by the lines 5 and 8 are the 4th and 7th lines in the matrix shown in FIG. 6, respectively. , as shown in Figure 10b.
  • the pilot sequence of each uplink subscriber can also be adjusted in the same manner as in the foregoing step 702.
  • Step 903 The VCE intercepts a sequence of consecutive pilot sequences in the pilot sequence allocated on each uplink subscriber line as a shortened pilot sequence.
  • the process of determining the shortened pilot sequence may be: binary representation of the minimum and maximum matrix row numbers corresponding to the used pilot sequences, and then comparing from low to high order (right to left order) Two binary numbers, determining the highest bit X whose numbers are not equal, the shortened number of pilot sequences on each line in the orthogonal training pilot sequence matrix is ⁇ , if the starting column number is start, Then the number of columns terminated is start+ -l.
  • the position of the start can be arbitrarily selected in the number of columns of the matrix as needed, and is not limited herein.
  • the method can also be applied to the previous embodiment. In this step, the shortened pilot sequence can also be determined by using the method in the previous embodiment. As long as the shortened pilot sequences satisfy the orthogonal relationship.
  • the binary number of the fourth row is 0000000000000100
  • the binary number of the seventh row is 0000000000000111
  • the highest unequal bit of the two binary numbers is found to be the second bit
  • the shortened pilot sequence corresponds to The number of columns is 4.
  • the shortened pilot sequences are as shown in Fig. 10c, and the number of rows is the fourth and seventh rows, and the number of columns is the pilot sequence corresponding to start to start+3.
  • the VCE may also select a pilot sequence having a discontinuous number of columns among the pilot sequences allocated on each uplink subscriber line as the shortened pilot sequence. The orthogonality is satisfied between the shortened pilot sequences.
  • the pilot sequence with the number of rows 4 and 7 is used, and the VCE can select the pilot sequence with the number of columns W and K2 in the matrix to form a shortened pilot sequence, where kl and k2 are discontinuous, but by
  • the method is equally applicable to the previous embodiment. In this step, the shortened pilot sequence can always be determined using the method in the previous embodiment. As long as the shortened pilot sequences satisfy the orthogonal relationship.
  • the transmitting end of each uplink subscriber line can transmit the modulated signal of the shortened pilot sequence, and after receiving the modulated signal of the crosstalked pilot sequence, the receiving end receives the modulated signal of the pilot sequence.
  • the corresponding error samples are calculated and sent to the VCE.
  • Step 904 The VCE receives an error sample corresponding to the shortened pilot sequence sent by the receiving end on each uplink subscriber line.
  • the error sample received by the VCE is that the transmitting end transmits the modulated signal of the pilot sequence shown in FIG. 10c, and the receiving end receives the signal and calculates the obtained error sample.
  • VCE is confirming After the error sample is collected, the next step is performed.
  • Step 905 The VCE calculates the crosstalk channel estimation parameter according to the received error sample and the shortened pilot sequence on each uplink subscriber line.
  • the embodiment of the invention greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the case that the subscriber line is not 100% fully activated, not only reduces the period length of the pilot sequence, but also shortens a period range.
  • the transmission time of the inner pilot sequence also reduces the number of received error samples received by the VCE, shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time for subscriber line activation and tracking, and improving the time. user experience.
  • the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • whether the pilot sequence according to the modulated signal transmitted by the transmitting end is a shortened pilot sequence when the VCE receives the error sample, the following steps may be performed to receive a shorter error.
  • the sample, the process of calculating the crosstalk channel estimation parameters by the VCE. Specific can include:
  • the starting position start (start position) of each error sample may be arbitrarily determined, and then the end position end (end position) of each error sample is determined, and It is ensured that the pilot sequences of the transmitting ends corresponding to the respective error samples between the start and end positions are orthogonal to each other.
  • each error sample is received from the start column, and corresponds to the pilot sequence of each transmitting end, if the number of rows of the pilot sequence in the orthogonal training pilot sequence matrix used is 1" or 0-/- 1, due to the special nature of the Walsh Matrix using 1 ⁇ '"(reserved line 0) or 2 °' ⁇ column can ensure orthogonality of the pilot sequences, as shown in FIG. 8f, in this case each error sample The number of columns to be terminated is also , that is, each error sample received is a continuous error sample between the number of columns from start to start+w+W-1 or start+Ll.
  • each error sample is received from the start column, and the minimum and maximum matrix corresponding to the used pilot sequence (the orthogonal training pilot sequence matrix) is represented by a binary corresponding to the pilot sequence of each transmitting end.
  • the line number compares the two binary numbers from the low order to the high order (from right to left) to determine the highest bit X of which the numbers are not equal, then the number of columns satisfying the orthogonal pilot sequence can be 2 columns.
  • the number of termination columns of each error sample that is, the received error samples are consecutive error samples whose number of columns is from start to start + 2 ⁇ -1.
  • VCE selects the number of consecutive columns in each error sample for reception, but it is necessary to ensure that the pilot sequences of the respective transmitting ends corresponding to the number of columns are orthogonal.
  • FIG. 11 is a schematic structural diagram of a crosstalk channel estimation apparatus according to an embodiment of the present invention.
  • the device can be a VCE and can include:
  • the matrix generating unit 1101 is configured to generate an orthogonal training pilot sequence matrix according to the user line size
  • the sequence allocating unit 1102 is configured to allocate a pilot sequence to each uplink user line i according to the orthogonal training pilot sequence matrix.
  • the transmitting end Ti of each of the uplink subscriber lines i transmits the modulated signal of the allocated pilot sequence, wherein the pilot sequences of any two of the uplink subscriber lines are orthogonal to each other;
  • a sample receiving unit 1103 configured to receive an error sample sent by the receiving end Ri of each uplink subscriber line i, where the error sample is obtained by the receiving end Ri according to a modulated signal of the received pilot sequence;
  • the channel estimation unit 1104 is configured to calculate a crosstalk channel estimation parameter according to the error sample and the pilot sequence of the uplink subscriber line.
  • the matrix generating unit 1101 first generates an orthogonal training pilot sequence matrix according to a subscriber line size of a system such as a vectored DSL system, and the orthogonal training pilot sequence may be a Walsh matrix.
  • the sequence allocating unit 1102 When the user is in the showtime state when the user goes online, the sequence allocating unit 1102 only allocates the pilot sequence on the line for the user on the line, and the orthogonality is satisfied between the pilot sequences on the uplink user line.
  • There are a plurality of allocation methods which may be an element of a certain row in the matrix as a pilot sequence on a certain line, or a partial element in a certain row may be used as a pilot sequence on a certain line, or may be selected.
  • the channel estimating unit 1104 calculates a crosstalk channel estimation parameter, such as crosstalk cancellation, according to the received error samples sent by each receiving end and the pilot sequence on the line.
  • the matrix W and the vector precoding matrix P are the matrix W and the vector precoding matrix P.
  • the DALAM terminal can adjust the crosstalk canceller and the vector precoder according to the W and P determined by the VCE, and combine the uplink and downlink processing by the crosstalk canceller and the vector precoder to achieve the effect of eliminating the far-end crosstalk. .
  • the embodiment of the present invention greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter by using the above unit, especially in the case that the subscriber line is not 100% fully activated, not only reduces the period length of the pilot sequence, but also shortens the length of the pilot sequence.
  • the transmission time of the pilot sequence in a cycle range also reduces the number of received error samples received by the VCE, shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, and further shortening the time of subscriber line activation and tracking. , improved user experience.
  • the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • FIG. 12 it is a schematic structural diagram of another crosstalk channel estimation apparatus according to an embodiment of the present invention.
  • the apparatus may be a VCE, and may include a sequence selection unit 1205 in addition to the matrix generation unit 1201, the sequence allocation unit 1202, the sample receiving unit 1203, and the channel estimation unit 1204.
  • the matrix generating unit 1201 and the channel estimating unit 1204 are similar to the matrix generating unit 1101 and the channel estimating unit 1104 in the previous embodiment, and are not described herein again.
  • the sequence allocating unit 1202 may specifically allocate the rows in the orthogonal training pilot sequence matrix as a pilot sequence to each uplink user line i according to the uplink sequence of the online user;
  • the row corresponding to the port number in the orthogonal training pilot sequence matrix is used as a pilot sequence according to the port number of the online user, and is allocated to the uplink user line corresponding to the port number.
  • the sequence allocating unit 1202 may further include: a first adjusting sub-unit 12021, configured to: when there is an uplink user line offline, replace a pilot sequence on a line with the largest number of lines in the orthogonal training pilot sequence matrix with the orthogonal training pilot The pilot sequence with the smallest number of unused lines in the sequence matrix.
  • a first adjusting sub-unit 12021 configured to: when there is an uplink user line offline, replace a pilot sequence on a line with the largest number of lines in the orthogonal training pilot sequence matrix with the orthogonal training pilot The pilot sequence with the smallest number of unused lines in the sequence matrix.
  • a second adjusting sub-unit 12022 configured to allocate, when the online subscriber line is activated, an unused line in the orthogonal training pilot sequence matrix as a pilot sequence to the active line, and make each line
  • the pilot sequences on the active line are orthogonal between the least columns.
  • the second adjustment sub-unit 12022 is specifically configured to allocate a pilot sequence with a smaller number of rows in the orthogonal training pilot sequence matrix to the active line, and minimize the number of unused lines.
  • the pilot sequence is reassigned as a new pilot sequence to the line on which the pilot sequence with the smaller number of lines is used.
  • the sequence selecting unit 1205 is configured to: after the pilot sequence on each of the uplink subscriber lines is allocated to the online user according to the orthogonal training pilot sequence matrix, select, in the pilot sequence of each uplink subscriber line i, The partial pilot sequence is used as a shortened pilot sequence to cause the transmitting terminal Ti to transmit the modulated signal of the shortened pilot sequence, wherein any two of the shortened pilot sequences are orthogonal to each other.
  • the sequence selection unit 1205 may be configured to: in the pilot sequence of each of the uplink subscriber lines i, intercept a sequence of consecutive pilot sequences as the shortened pilot sequence; or, in each of the In the pilot sequence of the uplink user line, a pilot sequence with a discontinuous number of columns is selected as the shortened pilot sequence.
  • the sample receiving unit 1203 may include:
  • a position determining sub-unit 12031 configured to determine a start position and an end position of the error samples sent by all the receiving ends, between the pilot sequences used by the transmitting end corresponding to all the error samples between the starting position and the ending position Orthogonal to each other; wherein each error sample between the start position and the end position may be continuous or discontinuous, whether continuous or discontinuous, as long as the receiving subunit 12032 is guaranteed All error samples between the starting position and the ending position are received.
  • the sequence allocating unit 1202 uses the row in the orthogonal training pilot sequence matrix as a guide according to the uplink order of the online user or the port number of the online user.
  • the frequency sequence is allocated to the line of the online user, and is used for the offline and uplink of the online subscriber line by the first adjustment subunit 12021 and the second adjustment subunit 12022, respectively.
  • the allocation adjustment is performed in the case where the line is activated, and then the sequence selection unit 1205 selects a part of the pilot sequence as the shortened pilot sequence on the allocated pilot sequence, and the modulated signal of the shortened pilot sequence is transmitted by the transmitting end to receive
  • the error sample is obtained, and the error sample is sent to the sample receiving unit 1203, and the position determining subunit 12031 determines the receiving error sample.
  • the start position and the end position, the receiving subunit 12032 receives the shortened error samples, and finally the channel estimation unit 1204 calculates the crosstalk channel estimation parameters, such as the crosstalk cancellation matrix, according to the received shortened error samples and the pilot sequences on the respective lines. w and the vector precoding matrix P.
  • the embodiment of the invention greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the case that the subscriber line is not 100% fully activated, not only reduces the period length of the pilot sequence, but also shortens a period range.
  • the transmission time of the inner pilot sequence also reduces the number of received error samples received by the VCE, shortens the time for receiving the error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time for subscriber line activation and tracking, and improving the time. user experience.
  • the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.
  • FIG. 13 is a schematic structural diagram of a crosstalk channel estimation system according to an embodiment of the present invention.
  • the system may include a VCE 1301, at least two uplink subscriber lines, a transmitting terminal Ti 1302 and a receiving terminal Ri 1303 of each uplink subscriber line i.
  • the VCE 1301 is configured to generate an orthogonal training pilot sequence matrix according to the user line size, and allocate a pilot sequence to each uplink user line i according to the orthogonal training pilot sequence matrix, where any two lines of the uplink user line
  • the pilot sequences are orthogonal to each other; the error samples sent by the receiving end Ri 1303 of each of the uplink subscriber lines i are received; and the crosstalk channel estimation parameters are obtained according to the error samples and the pilot sequences of the uplink subscriber lines;
  • a transmitting end Ti 1302 configured to send, to the receiving end Ri 1303, a modulation signal of a pilot sequence allocated by the VCE to the uplink subscriber line i;
  • the receiving end Ri 1303 is configured to obtain an error sample according to the modulated signal of the received pilot sequence, and send the error sample to the VCE.
  • the embodiment of the invention greatly enlarges the scale of the pilot sequence used for calculating the crosstalk channel estimation parameter, especially in the case that the subscriber line is not 100% fully activated, not only reduces the period length of the pilot sequence, but also shortens a period range.
  • the transmission time of the inner pilot sequence also reduces the error samples received by the VCE
  • the number of receptions shortens the time for receiving error samples, thereby shortening the estimation time of the crosstalk channel, further shortening the time for subscriber line activation and tracking, and improving the user experience.
  • the calculation amount is saved, the burden on the CPU is reduced, and the occupation of the uplink channel by the downlink feedback channel is saved.

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Description

一种串扰信道估计方法、 装置及系统
技术领域
本发明涉及通信技术领域，尤其涉及一种串扰信道估计方法、装置及系统。
背景技术
xDSL ( DSL, Digital Subscriber Line, 数字用户线路）是一种在电话双 绞线（无屏蔽双绞线， Unshielded Twist Pair, UTP )传输的高速数据传输技术， 提供多路 xDSL接入的系统叫做 DSL接入复用器（DSLAM )。 由于电磁感应原 理， DSLAM接入的多路信号之间， 会相互产生干扰， 称为串扰， 如近端串扰 ( NEXT )和远端串扰（ FEXT ), 其中， 近端串扰（ NEXT )对系统的性能不 会产生太大的危害， 而由于 xDSL使用的频段越来越宽， 远端串扰（FEXT )会 愈发严重地影响线路的传输性能， 远端串扰（FEXT )如图 1所示， 会使一些线 路速率低、 性能不稳定、 甚至不能开通等， 最终导致 DSLAM的出线率比较低。
目前业界提出了 Vectored - DSL技术，主要利用在 DSLAM端进行联合收发 的可能性， 使用信号处理的方法来抵消 FEXT的干扰， 即对于下行， 如图 2a所 示， 在 DSLAM端引入一个向量预编码器 P做信号的联合发送， 在用户端分别 接收； 对于上行， 如图 2b所示， 在用户端分别发送， 在 DSLAM端引入一个串 扰抵消器 W , 做信号的联合接收处理， 抵消串扰。 i l P可以称为串扰信道 估计参数， 该获得串扰信道估计参数的过程即为对串扰信道估计的过程，在该 过程中， 发送端各个收发器在同步符号（ Sync Symbol )上调制导频序列（ Pilot Sequence ), 接收器在接收端测量同步符号上由串扰引起的误差样本（Error Sample ), 接收器将误差样本传递给 VCE ( Vectoring Control Entity, 矢量化控 制实体）， VCE根据导频序列和误差样本计算出串扰氐消矩阵 W和与向量预编 码矩阵 P。
现有技术中在采用上述方法进行串扰信道估计时， 对于规模为 100线的系 统， 需要长度为 128的 pilot sequence, 在不丟失误差样本的情况下， 大约需要 8.224秒，该 pilot sequence的规模虽然可以用于估计该系统中所有线路之间的串 扰信道， 但根据现网的实际情况， 系统中的用户在线率不会达到 100%, 也就 是说，系统中很难出现需要估计全部串扰信道的情况，这就会造成下面的结果： 不论系统有 1条线路处于 showtime状态， 还是 99条线路处于 showtime状态， 当 有一条新的用户线路激活时， 都按照全长的 pilot sequence进行串扰信道估计， 也即按照最大的时间进行初始化， 这使得用户线路上线时间非常长，严重影响 用户体验。
发明内容
本发明实施例提供一种串扰信道估计方法、装置及系统， 能够缩短串扰信 道估计的时间。
为了解决上述技术问题， 本发明实施例的技术方案如下：
一种用户线路的串扰信道估计方法， 包括：
矢量化控制实体 VCE根据所述用户线路的规模生成正交训练导频序列矩 阵；
所述 VCE根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分 配导频序列， 所述分配的导频序列经调制后由所述每条上线用户线路 i上的发 送端 Ti发送出去， 其中， 上线用户线路中任意两条线路的导频序列相互正交； 所述 VCE接收所述每条上线用户线路 i的接收端 Ri发送的误差样本， 所 述误差样本由所述接收端 Ri根据接收到的导频序列的调制信号获得；
所述 VCE根据已接收到的所有误差样本及所述上线用户线路的导频序列 计算获得串扰信道估计参数；
一种用户线路的串扰信道估计装置， 包括：
矩阵生成单元， 用于根据所述用户线路的规模生成正交训练导频序列矩 阵；
序列分配单元，用于根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频序列， 所述分配的导频序列经调制后由所述每条上线用户线路 i上的发送端 Ti发送出去， 其中， 上线用户线路中任意两条线路的导频序列相 互正交；
样本接收单元， 用于接收所述每条上线用户线路 i的接收端 Ri发送的误 差样本， 所述误差样本由所述接收端 Ri根据接收到的导频序列的调制信号获 付；
信道估计单元，用于根据已接收到的所有误差样本及所述上线用户线路的 导频序列计算获得串扰信道估计参数。 一种串扰信道估计系统， 包括 VCE、 每条上线用户线路 i的发送端 Ti及 接收端 Ri,
所述 VCE, 用于根据所述用户线路夫人的规模生成正交训练导频序列矩 阵；根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频序列， 其中， 上线用户线路中任意两条线路的导频序列相互正交；接收所述每条上线 用户线路 i的接收端 Ri发送的误差样本； 根据已接收到的所有误差样本及所 述上线用户线路的导频序列计算获得串扰信道估计参数；
所述发送端 Ti,用于向所述接收端 Ri发送所述 VCE为上线用户线路 i分 配的导频序列的调制信号；
所述接收端 Ri, 用于根据接收到的导频序列的调制信号获得误差样本， 并将所述误差样本发送至所述 VCE。
本发明实施例通过 VCE预先生成正交训练导频序列矩阵， 然后根据该矩 阵只为上线的用户分配线路上的导频序列，并根据该上线用户线路上的导频序 列最终确定串扰信道估计参数。该方法相对于现有技术中无论线路状态如何均 为每条用户线路分配导频序列的方法，大大筒化了用于计算串扰信道估计参数 的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下， 不仅降低了 导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间，也减少了
VCE接收的误差样本的接收数量， 缩短了接收误差样本的时间， 从而缩短了 串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了 用户体验。 而且， 节省了计算量， 减轻了 CPU的负担， 节省了下行反馈通道 对上行信道的占用。
附图说明
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施 例或现有技术描述中所需要使用的附图作筒单地介绍，显而易见地， 下面描述 中的附图仅仅是本发明的一些实施例， 对于本领域普通技术人员来讲，在不付 出创造性劳动性的前提下， 还可以根据这些附图获得其他的附图。
图 1是多路 xDSL接入的系统下远端串扰的示意图；
图 2a是在 DSLAM端引入向量预编码器 P做信号联合发送的示意图； 图 2b是在 DSLAM端引入串扰抵消器 W做信号联合接收的示意图； 图 3是本发明实施例一种串扰信道估计方法的流程图；
图 4是本发明实施例中误差样本的生成过程示意图；
图 5是本发明实施例另一种串扰信道估计方法的流程图 ；
图 6是图 5所示实施例中正交训练导频序列矩阵的示意图 ；
图 7是本发明实施例另一种串扰信道估计方法的流程图；
图 8a是图 7所示实施例中线路导频序列分配示意图； 示意图；
图 8d~8e是图 7所示实施例中存在上线用户线路正在激活时线路导频序列 分配示意图；
图 8f是图 7所示实施例中缩短的导频序列的示意图；
图 9是本发明实施例另一种串扰信道估计方法的流程图；
图 10a是图 9所示实施例中正交训练导频序列矩阵的示意图；
图 10b是图 9所示实施例中线路导频序列分配示意图；
图 10c是图 9所示实施例中缩短的导频序列的示意图；
图 10d是图 9所示实施例中另一缩短的导频序列的示意图；
图 11是本发明实施例一种串扰信道估计装置的结构示意图；
图 12是本发明实施例另一种串扰信道估计装置的结构示意图；
图 13是本发明实施例一种串扰信道估计系统的结构示意图。
具体实施方式
下面将结合本发明实施例中的附图，对本发明实施例中的技术方案进行清 楚、 完整地描述， 显然， 所描述的实施例仅仅是本发明一部分实施例， 而不是 全部的实施例。基于本发明中的实施例， 本领域普通技术人员在没有做出创造 性劳动前提下所获得的所有其他实施例， 都属于本发明保护的范围。
参见图 3 , 为本发明实施例一种串扰信道估计方法的流程图。
该方法可以包括：
步骤 301 , VCE按照根据用户线路的规模生成正交训练导频序列矩阵。 在本发明实施例中， VCE是整个 Vectored DSL的控制实体， 在如图 2a、 b的 DSLAM中， VCE首先根据系统如 vectored DSL系统中，用户线路的规模 或数量， 生成正交的训练导频序列矩阵， 后续在分配线路上的导频序列时， 可 以基于该训练导频序列矩阵直接进行分配。 其中， 该正交训练导频序列可以是 Walsh矩阵。
步骤 302, VCE根据正交训练导频序列矩阵为每条上线用户线路 i分别分 配导频序列。
当该系统中有用户上线时即处于 showtime状态时， VCE并非与现有技术 一样无论线路状态如何均为每条用户线路分配导频序列， 而是采用本步骤所 述， 只是根据上步骤中的正交训练导频序列矩阵， 只为上线的用户分配线路上 的导频序列， 且上线用户线路上的导频序列之间正交。 该分配方式有多种， 可 以是将该矩阵中的某一行的元素作为某一线路上的导频序列，也可以将某一行 中的部分元素作为某一线路上的导频序列，还可以是选取该矩阵中的其它元素 组成某一线路上的导频序列， 具体请参见后续实施例的描述。
在 VCE为每条上线用户线路 i分配导频序列后， 每条线路 i上的发送端 Ti即可依据分配的导频序列向对端即接收端 Ri发送导频序列的调制信号。 其 中， "i" 代表某一条上线用户线路， Ti、 Ri分别代表该线路上的发送端、 接收 端， 仅为表述方便， 并非特指。
对于上行信号，各线路上的发送端即为各用户端，发送相互呈正交关系的 导频序列的调制信号至 DSLAM端； 对于下行信号，各线路上的发送端即为在 DSLAM端， 通过每一个子载波发送互成正交关系的导频序列的调制信号至各 用户端。
每条线路 i上的发送端 Ti根据 VCE分配的导频序列在每个同步符号进行 调制生成调制信号， 然后向接收端 Ri发送， 其中， 对导频序列调制生成调制 信号的过程，如将导频序列调制在星座图上的星座点，对于本领域技术人员来 说， 根据上述描述即可实现。
步骤 303, VCE接收每条上线用户线路 i的接收端 Ri发送的误差样本。 发送端 Ti发送导频序列的调制信号后， 由该线路 i上的接收端 Ri进行接 收， 信号在线路上传输的过程中不同线路之间会产生远端串扰， 所以接收端 Ri接收到的信号与发送端 Ti发送的信号之间可能存在一定的差异， 接收端 Ri 根据接收到的导频序列的调制信号判决出发送端 Ti发送的信号， 并计算接收 信号与发送信号之间的差异， 获得误差样本， 例如接收端 Ri根据接收到的信 号判决出发送端 Ti发送的星座点， 并且将接收信号与判决星座点的差作为误 差样本。
在该误差样本的计算过程中，对于上、 下行误差样本的计算均可以采用上 述过程，对于上行的误差样本，由于发送端 Ti是 VTU-R也即网络管理系统侧， 接收端 Ri是 VTU-0为用户侧， 而 VTU-R使用的导频序列是 VCE配置给 VTU-0并且由 VTU-0通过消息的方式通知到 VTU-R的， 因此上行发送的导 频序列对于 VTU-0而言是已知的， 从而也可以直接使用发送的星座点作为参 考点， 并计算接收点与发送星座点的差作为误差样本。 上述接收端 Ri根据接 收到的信号计算误差样本的过程，对于本领域技术人员来说，根据上述描述即 可实现。 接收端 Ri在计算获得误差样本后， 将该误差样本发送至 VCE。
以上过程， 如图 4所示， 以两条上线用户线路上的导频序列为例， 发送端 发送导频序列调制信号 xl , x2,各接收器接收到导频序列调制信号 yl , y2后， 根据信号 yl , y2判决出发送端的调制信号 xl , x2, 并且分别计算出误差样本 1 , 误差样本 2, 发送至 VCE。
步骤 304, VCE根据已接收到的所有误差样本及上线用户线路上的导频序 列计算获得串扰信道估计参数。
VCE根据接收到的误差样本及各线路上的导频序列计算串扰信道估计参 数， 如串扰抵消矩阵 W和与向量预编码矩阵 P, 在获得 W和 P后， DALAM 端即可根据 VCE确定的 W和 P调整串扰抵消器和向量预编码器，通过串扰抵 消器和向量预编码器对上下行联合处理， 达到消除远端串扰的效果。 其中， 对 于 VCE根据误差样本及导频序列计算 W、 P等串扰信道估计参数的过程， 对 于本领域的技术人员来说， 根据上述描述即可实现。
本发明实施例通过 VCE预先生成正交训练导频序列矩阵， 然后根据该矩 阵只为上线的用户分配线路上的导频序列，并根据该上线用户线路上的导频序 列最终确定串扰信道估计参数。该方法相对于现有技术中无论线路状态如何均 为每条用户线路分配导频序列的方法，大大筒化了用于计算串扰信道估计参数 的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下， 不仅降低了 导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间，也减少了 VCE接收的误差样本的接收数量， 缩短了接收误差样本的时间， 从而缩短了 串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了 用户体验。 而且， 节省了计算量， 减轻了 CPU的负担， 节省了下行反馈通道 对上行信道的占用。
参见图 5 , 为本发明实施例另一种串扰信道估计方法的流程图。
该方法可以包括：
步骤 501 , VCE按照用户线路的规模生成正交训练导频序列矩阵。
例如， vectored DSL系统的用户线路规模为 24对线， 则 VCE可生成规模 为 Μ χ Μ的 Walsh矩阵， 如图 6所示， 其中， M为 ^1。82^1 (若该矩阵中的首 行为空闲行， 不被分配和占用 )或者 2 1° (该矩阵的首行参与分配）， N 为
24。 需要说明的是， 在本文所有所述的方法中， 矩阵的行都从 0开始编号， 即 首行为第 0行。 上线用户的线路上。
本步骤中 VCE只为上线的用户分配线路上的导频序列， 本实施例中以选 取正交训练导频序列矩阵中某一行的元素作为某一线路上的导频序列为例进 行说明， 例如线路 2上线即处于 showtime状态， 则可以选择正交训练导频序 列矩阵中的第 1行元素作为该线路上的导频序列。
在存在多条上线线路时，具体的为线路分配导频序列的方法有多种，例如： VCE按照上线用户的上线顺序依次将正交训练导频序列矩阵中的行作为 导频序列， 分配至每条上线用户线路 i上； 或者，
VCE按照上线用户的端口号将正交训练导频序列矩阵中端口号对应的行 作为导频序列， 分配至该端口号对应的上线用户的线路上， 其中， 端口号与该 矩阵中的行数——对应。
进一步的， 当存在上线用户线路下线时，将正交训练导频序列矩阵中使用 行数最大的线路上的导频序列，更换为正交训练导频序列矩阵中未被使用的行 数最小的导频序列；
当存在上线用户线路正在激活时，将正交训练导频序列矩阵中未被使用的 行作为导频序列分配至正在激活的线路上，并使得每条正在激活的线路上所分 配的导频序列之间在部分列上正交，优选的使得每条正在激活的线路上所分配 的导频序列之间在最少的列上正交。例如，将正交训练导频序列矩阵中行数较 小的导频序列分配至正在激活的线路上，并将正交训练导频序列矩阵中未被使 用的行数最小的导频序列作为新的导频序列，重新分配至已使用行数较小的导 频序列的线路上。
上述分配过程的具体实施例请参照后续描述。 该步骤完成后， 可以直接执 行与上述步骤 303、 304相同的操作， 也可以继续执行以下步骤 503~505。
步骤 503 , VCE在每条上线用户线路的导频序列上，选取部分导频序列作 为缩短的导频序列。
在本实施例中， 在 VCE为各线路分配导频序列后， 还可以进一步在分配 的导频序列中选取部分导频序列以缩短发送端发送的各导频序列的规模，筒化 后续计算误差样本的过程及缩短获得误差样本及 W、 P的时间。各线路上的缩 短的导频序列之间需要满足正交性。
选取部分导频序列的具体过程可以是：在每条上线用户线路的导频序列中 截取一段列数连续的导频序列， 作为缩短的导频序列； 或者， 在每条上线用户 线路的导频序列中挑选列数不连续的导频序列，作为缩短的导频序列等等。 总 之， 只要满足缩短的导频序列之间正交即可。
在确定各上线用户线路上缩短的导频序列后，各上线用户线路上的发送端 即可发送该缩短的导频序列的调制信号，接收端接收到串扰后的导频序列的调 制信号后， 计算出对应的误差样本， 并发送至 VCE。
步骤 504, VCE接收各上线用户线路上的接收端发送的缩短的导频序列对 应的误差样本。
由于发送端发送的调制信号所依据的导频序列为缩短后的序列，接收端计 算出的误差样本也即与该缩短的导频序列所对应的误差样本。该计算误差样本 的方法与前述步骤 303中的相应描述类似，只是接收到的导频序列的调制信号 有所不同， 此处不再赘述。
在另一实施例中， VCE在接收误差样本时， 还可以进一步确定接收误差 样本的起止位置， 以接收更短的误差样本， 筒化下一步骤的计算过程。
步骤 505 , VCE根据接收到的误差样本及上线用户线路上的缩短的导频序 列计算获得串扰信道估计参数。
该计算获得串扰信道估计参数的方法与前述步骤 304类似，只是计算所依 据的导频序列有所不同， 此处不再赘述。
本发明实施例相对于前述实施例进一步缩短了各线路上的导频序列，更加 降低了导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间， 也 更减少了 VCE接收的误差样本的接收数量， 缩短了接收误差样本的时间， 从 而更加缩短了串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的 时间， 改善了用户体验。
参见图 7 , 为本发明实施例另一种串扰信道估计方法的流程图。
该方法可以包括：
步骤 701 , 在 VCE初始化过程中， 按照 vectored DSL系统规模生成正交 训练序列矩阵。
本实施例中仍以 vectored DSL系统规模为 24对线为例，则 VCE可生成规 模为 Μ χ Μ的 Walsh矩阵， 如图 6所示， 其中， M为 ^1^^1 (若该矩阵中的 首行为空闲行， 不被分配和占用）或者 ^1。82" , N为 24。 本实施例中正交训练 序列矩阵以 32 32的 Walsh矩阵为例进行说明。
步骤 702 , VCE按照上线用户的上线顺序依次将正交训练导频序列矩阵中 的行作为导频序列， 分配至各上线用户的线路上。
假设线路 4,23, 12,9依次上线， 将正交训练导频序列矩阵中 1~4行按照线 路激活顺序依次分配给 4,23,12,9线路， 如图 8a所示， 其中， 首行（图中第 0 行）保留。
当存在上线用户线路下线时，将正交训练导频序列矩阵中使用行数最大的 线路上的导频序列，更换为正交训练导频序列矩阵中未被使用的行数最小的导 频序列。
例如线路 23下线， 则将行数最大（第 4行） 的线路 9上的导频序列更好 为未被使用的行数最小 （第 2行） 的导频序列， 如图 8b~8c所示。
当存在上线用户线路正在激活时，将正交训练导频序列矩阵中未被使用的 行作为导频序列分配至正在激活的线路上，并使得每条正在激活的线路上所分 配的导频序列在最少的列上满足正交性。例如，将正交训练导频序列矩阵中行 数较小的导频序列分配至正在激活的线路上，并将正交训练导频序列矩阵中未 被使用的行数最小的导频序列作为新的导频序列重新分配至已使用行数较小 的导频序列的线路上。
例如， 线路 4,23,12,9为 showtime状态线路， 线路 11和 5正在激活， 在线 路 11和 5激活之前， 将正交训练导频序列矩阵中的第 1~4行按照线路激活顺 序依次分配给 4,23,12,9线路， 首行（第 0行）保留， 当线路 11和 5正在激活 时， 则将第 1~2行依次分配给正在激活的线路 11和 5 , 并将未被使用的行数 最小的导频序列第 5~6行作为新的导频序列重新分配至已使用行数较小的导 频序列的线路 4,23上， 也即将矩阵最上面的行分配至正在激活的线路， 将已 有的 showtime线路的导频序列用矩阵中未被使用的行数最小的导频序列来替 换， 如图 8d~8e所示。
该步骤完成后， 可以直接执行与上述步骤 303、 304相同的操作， 也可以 继续执行以下步骤 703~705。
步骤 703 , VCE在各上线用户线路上分配的导频序列中截取一段列数连续 的导频序列， 作为缩短的导频序列。
假设系统中已经被使用的最大的导频序列的行数为 由于 Walsh Matrix 的特殊性质，使用 ^1 2"") (第 0行保留 )或 2 ° 'Ί就可以保证正交性，后续 VCE 计算 w和 Ρ所应该依据的误差样本中列的个数为 2「^+1)Ί (第 0行保留 )或 2Γΐ082'Ί , 假设所选取的各缩短的导频序列的开始列位置为 start, 则根据各导频 序列的开始列位置 start, 可以得到 VCE所截取的一段列数连续的各导频序列 为列数从 start到 start+ ^w+ Ll或到 start+^82' -1之间的导频序列， 如图 8f 所示。 其中， start的位置可以根据需要在矩阵的列数中任意选择， 此处不做 限定。
在本实施例中， 已经被使用的最大的导频序列的行数为 Z为 4, 则所截取 的各导频序列为正交训练导频序列中列数从 start到 start+3之间的各导频序列。
在确定各上线用户线路上缩短的导频序列后，各上线用户线路上的发送端 即可发送该缩短的导频序列的调制信号，接收端接收到串扰后的导频序列的调 制信号后， 计算出对应的误差样本， 并发送至 VCE。
步骤 704, VCE接收各上线用户线路上的接收端发送的缩短的导频序列对 应的误差样本。
本实施例中， VCE接收到的误差样本即为接收端接收发送端发送的图 6 所示正交导频序列中行数为第 1 ~4行， 列数为从 start到 start+3所对应的四条 线路上的导频序列的调制信号而获得的误差样本。 VCE在确认收齐该误差样 本后， 执行下一步骤。
步骤 705, VCE根据接收到的误差样本及各上线用户线路上的缩短的导频 序列计算获得串扰信道估计参数。
本发明实施例大大筒化了用于计算串扰信道估计参数的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下，不仅降低了导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间， 也减少了 VCE接收的误差样本 的接收数量， 缩短了接收误差样本的时间， 从而缩短了串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了用户体验。 而且， 节省 了计算量， 减轻了 CPU的负担， 节省了下行反馈通道对上行信道的占用。
参见图 9, 为本发明实施例另一种串扰信道估计方法的流程图。
该方法可以包括：
步骤 901 , 在 VCE初始化过程中， 按照 vectored DSL系统规模生成正交 训练序列矩阵。
本实施例中仍以图 6所示的正交训练导频序列为例进行说明。
步骤 902, VCE按照上线用户的端口号将正交训练导频序列矩阵中端口号 对应的行作为导频序列， 分配至上线用户的线路上。
端口号与该矩阵中的行数——对应， 如图 10a所示。
若当前系统中上线的用户线路为 5和 8, 则根据线路端口号 5、 8对应的 行， 线路 5、 8使用的导频序列分别为图 6所示矩阵中的第 4行和第 7行， 如 图 10b所示。 当存在上线用户线路下线或者上线用户正在激活的情况时，也可 以采用前述步骤 702中相同的方式调整各上线用户的导频序列。
该步骤完成后， 可以直接执行与上述步骤 303、 304相同的操作， 也可以 继续执行以下步骤 903~905。
步骤 903, VCE在各上线用户线路上分配的导频序列中截取一段列数连续 的导频序列， 作为缩短的导频序列。 在本实施例中，确定该缩短的导频序列的过程可以是： 二进制表示使用的 导频序列对应的最小及最大的矩阵的行号， 然后从低位到高位顺序（从右到左 顺序） 比较两个二进制数， 确定数字不相等的最高的位 X , 则缩短的各线路上 的导频序列在正交训练导频数列矩阵中对应的列数即为 ^ , 若起始列数为 start, 则终止列数即为 start+ -l。 其中， start的位置可以根据需要在矩阵的 列数中任意选择， 此处不做限定。 该方法同样可以适用于上一实施例， 本步骤 总也同样可以使用上一实施例中的方法确定缩短的导频序列。只要缩短的导频 序列之间满足正交关系即可。
例如， 本实施例中， 第 4行的二进制数为 0000000000000100, 第 7行的 二进制数为 0000000000000111 ,则找到两个二进制数的最高不等位 ^为第 2位， 则缩短的导频序列对应的列数为 即 4。 则缩短的各导频序列如图 10c所示， 为行数为第 4、 7行， 列数为从 start到 start+3所对应的导频序列。
在本发明的另一实施例中， VCE还可以在各上线用户线路上分配的导频 序列中挑选列数不连续的导频序列，作为缩短的导频序列。缩短的导频序列之 间满足正交性。
例如， 当前系统中使用行数为 4和 7的导频序列， VCE可以选择矩阵中 列数为 W、 K2的导频序列， 形成缩短的导频序列， 其中 kl与 k2不连续， 但 是由第 4行第 kl、 k2列的元素以及第 7行第 kl、 k2列的元素所组成的缩短的 各导频序列满足正交性， 也即行数为 4和 7的导频序列在 W和 点正交， 如 图 10d所示。该方法同样可以适用于上一实施例， 本步骤总也同样可以使用上 一实施例中的方法确定缩短的导频序列。只要缩短的导频序列之间满足正交关 系即可。
在确定各上线用户线路上缩短的导频序列后，各上线用户线路上的发送端 即可发送该缩短的导频序列的调制信号，接收端接收到串扰后的导频序列的调 制信号后， 计算出对应的误差样本， 并发送至 VCE。
步骤 904, VCE接收各上线用户线路上的接收端发送的缩短的导频序列对 应的误差样本。
本实施例中， VCE接收到的误差样本即为发送端发送图 10c 中所示的导 频序列的调制信号， 接收端接收到信号后计算获得的误差样本。 VCE在确认 收齐该误差样本后， 执行下一步骤。
步骤 905, VCE根据接收到的误差样本及各上线用户线路上的缩短的导频 序列计算获得串扰信道估计参数。
本发明实施例大大筒化了用于计算串扰信道估计参数的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下，不仅降低了导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间， 也减少了 VCE接收的误差样本 的接收数量， 缩短了接收误差样本的时间， 从而缩短了串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了用户体验。 而且， 节省 了计算量， 减轻了 CPU的负担， 节省了下行反馈通道对上行信道的占用。
在本发明的另一实施例中，无论发送端发送的调制信号所依据的导频序列 是否为缩短的导频序列， 在 VCE接收误差样本时， 还可以执行以下步骤， 以 接收更短的误差样本， 筒化 VCE后续计算串扰信道估计参数的过程。 具体的 可以包括：
VCE确定所有接收端发送的误差样本的起始位置及终止位置， 所述起始 位置与终止位置之间的所有误差样本所对应的发送端使用的导频序列之间相 互正交； 其中， 所述起始位置与终止位置之间的误差样本可以是连续的， 也可 以是不连续的， 无论是连续的还是不连续的， 只要保证这些误差样本对应的发 送端使用的导频序列之间相互正交即可。
接收所述起始位置与所述终止位置之间的所有误差样本。
其中，在确定各接收端发送的误差样本的起始位置时， 可以先任意确定各 误差样本中一开始位置 start (起始位置 ),然后确定各误差样本的终止位置 end (终止位置 ), 并保证该起始与终止位置之间的各误差样本分别对应的发送端 的导频序列之间相互正交。
具体的， 假设各误差样本均从第 start列开始接收， 则对应于各发送端的 导频序列， 如果使用的正交训练导频序列矩阵中导频序列的行数为 1」或 0-/ -1 , 由于 Walsh Matrix的特殊性质， 使用 1^'" (第 0行保留）或 2 ° 'Ί个 列就可以保证导频序列的正交性， 如图 8f 所示， 此时各误差样本的终止列数 也即
Figure imgf000015_0001
, 也即接收的各误差样本均为列数从 start 到 start+ w+W -l或 start+ Ll之间的连续的误差样本。 还可以是， 假设各误差样本均从第 start列开始接收， 则对应于各发送端 的导频序列， 用二进制表示使用的导频序列对应的最小及最大的矩阵（正交训 练导频序列矩阵）的行号， 然后从低位到高位顺序（从右到左顺序）比较两个 二进制数， 确定数字不相等的最高的位 X , 则满足正交的导频序列的列数就可 以是 2列， 如图 10c所示， 则此时各误差样本的终止列数也即 也即接收的 各误差样本均为列数从 start到 start+2^ -1之间的连续的误差样本。
也还可以是， VCE在各误差样本中挑选不连续的列数进行接收， 但需要 保证这些列数对应的各发送端的导频序列之间正交。
当然， VCE确定接收误差样本起始位置及终止位置的方法有多种， 只要 使起止位置与终止位置之间的各误差样本所对应的各发送端使用的导频序列 之间相互正交即可。 以上方式仅为举例， 此处不作具体限定。
以上各实施例仅为举例说明， 并非限定， 其中， 为上线用户分配导频序列 的多种方法、获得缩短导频序列的多种方法、接收缩短的误差样本的多种方法 等可以分别进行选择并组合形成新的技术方案， 此处不——列举。 以上为对本 发明方法实施例的描述， 下面对实现上述方法的装置进行介绍。
参见图 11 , 为本发明实施例一种串扰信道估计装置的结构示意图。
该装置可以为 VCE, 可以包括：
矩阵生成单元 1101 , 用于 ^据用户线路规模生成正交训练导频序列矩阵； 序列分配单元 1102, 用于根据所述正交训练导频序列矩阵为每条上线用 户线路 i分配导频序列，以使所述每条上线用户线路 i的发送端 Ti发送所分配 的导频序列的调制信号， 其中， 上线用户线路中任意两条线路的导频序列相互 正交；
样本接收单元 1103 , 用于接收所述每条上线用户线路 i的接收端 Ri发送 的误差样本， 所述误差样本由所述接收端 Ri根据接收到的导频序列的调制信 号获得；
信道估计单元 1104, 用于根据所述误差样本及所述上线用户线路的导频 序列计算获得串扰信道估计参数。
矩阵生成单元 1101首先根据系统如 vectored DSL系统的用户线路规模， 生成正交的训练导频序列矩阵， 该正交训练导频序列可以是 Walsh矩阵。 当该 系统中有用户上线时即处于 showtime状态时，序列分配单元 1102只为上线的 用户分配线路上的导频序列， 且上线用户线路上的导频序列之间满足正交性。 该分配方式有多种，可以是将该矩阵中的某一行的元素作为某一线路上的导频 序列，也可以将某一行中的部分元素作为某一线路上的导频序列，还可以是选 取该矩阵中的其它元素组成某一线路上的导频序列等。 各上线用户线路 i上的 发送端 Ti发送导频序列的调制信号后， 由线路上的接收端 Ri进行接收， 接收 端 Ri根据接收到的导频序列的调制信号计算接收信号与发送信号之间的差异 后， 获得误差样本， 将该误差样本发送至样本接收单元 1103 , 信道估计单元 1104根据接收到的各接收端发送的误差样本及线路上的导频序列计算串扰信 道估计参数， 如串扰抵消矩阵 W和与向量预编码矩阵 P。 在获得 W和 P后， DALAM端即可根据 VCE确定的 W和 P调整串扰抵消器和向量预编码器，通 过串扰抵消器和向量预编码器对上下行联合处理， 达到消除远端串扰的效果。
本发明实施例通过上述单元大大筒化了用于计算串扰信道估计参数的导 频序列的规模， 尤其在用户线没有 100%全部激活的情况下， 不仅降低了导频 序列的周期长度，缩短了一个周期范围内导频序列的发送时间，也减少了 VCE 接收的误差样本的接收数量， 缩短了接收误差样本的时间，从而缩短了串扰信 道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了用户体 验。 而且， 节省了计算量， 减轻了 CPU的负担， 节省了下行反馈通道对上行 信道的占用。
参见图 12, 为本发明实施例另一种串扰信道估计装置的结构示意图。 该装置可以为 VCE, 除了可以包括矩阵生成单元 1201 , 序列分配单元 1202, 样本接收单元 1203, 信道估计单元 1204之外， 还可以包括序列选取单 元 1205。 其中， 矩阵生成单元 1201 , 信道估计单元 1204分别与前一实施例中 的矩阵生成单元 1101 , 信道估计单元 1104类似， 此处不再赘述。
本实施例中， 序列分配单元 1202, 具体可以按照上线用户的上线顺序依 次将所述正交训练导频序列矩阵中的行作为导频序列，分配至每条上线用户线 路 i上； 还可以用于按照上线用户的端口号将所述正交训练导频序列矩阵中所 述端口号对应的行作为导频序列， 分配至所述端口号对应的上线用户线路上。
序列分配单元 1202还可以包括： 第一调整子单元 12021 , 用于当存在上线用户线路下线时， 将所述正交训 练导频序列矩阵中使用行数最大的线路上的导频序列，更换为所述正交训练导 频序列矩阵中未被使用的行数最小的导频序列。
第二调整子单元 12022, 用于当存在上线用户线路正在激活时， 将所述正 交训练导频序列矩阵中未被使用的行作为导频序列分配至正在激活的线路上， 并使得每条正在激活的线路上的导频序列之间在最少的列上正交。第二调整子 单元 12022, 具体的可以用于将所述正交训练导频序列矩阵中行数较小的导频 序列分配至所述正在激活的线路上，并将未被使用的行数最小的导频序列作为 新的导频序列， 重新分配至已使用所述行数较小的导频序列的线路上。
序列选取单元 1205 , 用于根据所述正交训练导频序列矩阵为上线用户分 配各所述上线用户线路上的导频序列之后， 在所述每条上线用户线路 i的导频 序列中， 选取部分导频序列作为缩短的导频序列， 以使所述发送端 Ti发送所 述缩短的导频序列的调制信号，其中，任意两个所述缩短的导频序列之间正交。 序列选取单元 1205, 具体的可以用于在所述每条上线用户线路 i的导频序列 中， 截取一段列数连续的导频序列， 作为所述缩短的导频序列； 或者， 在所述 每条上线用户线路的导频序列中，挑选列数不连续的导频序列，作为所述缩短 的导频序列。
样本接收单元 1203可以包括：
位置确定子单元 12031 , 用于确定所有接收端发送的误差样本的起始位置 及终止位置，所述起始位置与终止位置之间的所有误差样本所对应的发送端使 用的导频序列之间相互正交； 其中， 所述起始位置与终止位置之间的各误差样 本可以是连续的， 也可以是不连续的， 无论是连续的还是不连续的， 只要保证 接收子单元 12032, 用于接收所述起始位置与所述终止位置之间的所有误 差样本。
矩阵生成单元 1101 ^据系统规模生成正交的训练导频序列矩阵后， 序列 分配单元 1202按照所述上线用户的上线顺序或者上线用户的端口号将正交训 练导频序列矩阵中的行作为导频序列， 分配至上线用户的线路上， 并通过第一 调整子单元 12021和第二调整子单元 12022分别对上线用户线路下线和上线用 户线路激活的情况进行分配调整， 然后由序列选取单元 1205在分配的导频序 列上，选取部分导频序列作为缩短的导频序列， 由发送端发送该缩短的导频序 列的调制信号，接收端根据接收到的导频序列的调制信号计算接收信号与发送 信号之间的差异后， 获得误差样本， 将该误差样本发送至样本接收单元 1203, 由位置确定子单元 12031确定接收误差样本的起始位置及终止位置，接收子单 元 12032接收该缩短的误差样本， 最后再由信道估计单元 1204根据接收到的 缩短的误差样本及各线路上的导频序列计算串扰信道估计参数，如串扰抵消矩 阵 w和与向量预编码矩阵 P。
本发明实施例大大筒化了用于计算串扰信道估计参数的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下，不仅降低了导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间， 也减少了 VCE接收的误差样本 的接收数量， 缩短了接收误差样本的时间， 从而缩短了串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了用户体验。 而且， 节省 了计算量， 减轻了 CPU的负担， 节省了下行反馈通道对上行信道的占用。
参见图 13, 为本发明实施例一种串扰信道估计系统的结构示意图。
该系统可以包括 VCE 1301 , 至少两条上线用户线路， 每条上线用户线路 i的发送端 Ti 1302及接收端 Ri 1303。
VCE1301 , 用于根据用户线路规模生成正交训练导频序列矩阵； 根据所述 正交训练导频序列矩阵为每条上线用户线路 i分配导频序列， 其中， 上线用户 线路中任意两条线路的导频序列相互正交； 接收所述每条上线用户线路 i的接 收端 Ri 1303发送的误差样本； 根据所述误差样本及所述上线用户线路的导频 序列计算获得串扰信道估计参数；
发送端 Ti 1302, 用于向所述接收端 Ri 1303发送所述 VCE为上线用户线 路 i分配的导频序列的调制信号；
接收端 Ri 1303, 用于根据接收到的导频序列的调制信号获得误差样本， 并将所述误差样本发送至所述 VCE。
本发明实施例大大筒化了用于计算串扰信道估计参数的导频序列的规模， 尤其在用户线没有 100%全部激活的情况下，不仅降低了导频序列的周期长度， 缩短了一个周期范围内导频序列的发送时间， 也减少了 VCE接收的误差样本 的接收数量， 缩短了接收误差样本的时间， 从而缩短了串扰信道的估计时间， 进一步缩短了用户线路激活及 tracking的时间， 改善了用户体验。 而且， 节省 了计算量， 减轻了 CPU的负担， 节省了下行反馈通道对上行信道的占用。
以上所述的本发明实施方式， 并不构成对本发明保护范围的限定。任何在 本发明的精神和原则之内所作的修改、等同替换和改进等， 均应包含在本发明 的权利要求保护范围之内。

Claims

权 利 要 求
1、 一种用户线路的串扰信道估计方法， 其特征在于， 包括：
矢量化控制实体根据所述用户线路的规模生成正交训练导频序列矩阵； 所述矢量化控制实体根据所述正交训练导频序列矩阵为每条上线用户线 路 i分别分配导频序列， 所述分配的导频序列经调制后由所述每条上线用户线 路 i上的发送端 Ti发送出去， 其中， 上线用户线路中任意两条线路的导频序 列相互正交；
所述矢量化控制实体接收所述每条上线用户线路 i的接收端 Ri发送的误 差样本， 所述误差样本由所述接收端 Ri根据接收到的导频序列的调制信号获 得；
所述矢量化控制实体根据已接收到的所有误差样本及所述上线用户线路 的导频序列计算获得串扰信道估计参数。
2、 根据权利要求 1所述的方法， 其特征在于， 所述矢量化控制实体根据 所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频序列， 包括： 所述矢量化控制实体按照上线用户的上线顺序依次将所述正交训练导频 序列矩阵中的行作为导频序列， 分配至每条上线用户线路 i上； 或者，
所述矢量化控制实体按照上线用户的端口号将所述正交训练导频序列矩 阵中所述端口号对应的行作为导频序列，分配至所述端口号对应的上线用户线 路上。
3、 根据权利要求 2所述的方法， 其特征在于， 所述矢量化控制实体根据 所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频序列，还包括： 当存在上线用户线路下线时，将所述正交训练导频序列矩阵中使用行数最 大的线路上的导频序列，更换为所述正交训练导频序列矩阵中未被使用的行数 最小的导频序列；
当存在上线用户线路正在激活时，将所述正交训练导频序列矩阵中未被使 用的行作为导频序列分配至正在激活的线路上，并使得任意两条正在激活的线 路上的导频序列之间在最少的列上正交。
4、 根据权利要求 3所述的方法， 其特征在于， 所述将所述正交训练导频 序列矩阵中未被使用的行作为导频序列分配至正在激活的线路上， 包括： 将所述正交训练导频序列矩阵中行数较小的导频序列分配至所述正在激 活的线路上， 并将未被使用的行数最小的导频序列作为新的导频序列， 重新分 配至已使用所述行数较小的导频序列的线路上。
5、 根据权利要求 1至 4中任意一项所述的方法， 其特征在于， 所述矢量 化控制实体根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导 频序列之后， 还包括：
所述矢量化控制实体在所述每条上线用户线路 i的导频序列中，选取部分 导频序列作为缩短的导频序列， 以使所述发送端 Ti发送所述缩短的导频序列 的调制信号， 其中， 任意两个所述缩短的导频序列之间正交。
6、 根据权利要求 5所述的方法， 其特征在于， 所述矢量化控制实体在所 述每条上线用户线路 i的导频序列中，选取部分导频序列作为缩短的导频序列， 包括：
在所述每条上线用户线路 i的导频序列中，截取一段列数连续的导频序列， 作为所述缩短的导频序列； 或者，
在所述每条上线用户线路的导频序列中，挑选列数不连续的导频序列，作 为所述缩短的导频序列。
7、 根据权利要求 1至 6中任意一项所述的方法， 其特征在于， 所述矢量 化控制实体接收所述每条上线用户线路 i上的接收端 Ri发送的误差样本， 包 括：
确定所有接收端发送的误差样本的起始位置及终止位置，所述起始位置与 接收所述起始位置与所述终止位置之间的所有误差样本。
8、 一种用户线路的串扰信道估计装置， 其特征在于， 包括：
矩阵生成单元， 用于根据所述用户线路的规模生成正交训练导频序列矩 阵；
序列分配单元，用于根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频序列， 所述分配的导频序列经调制后由所述每条上线用户线路 i上的发送端 Ti发送出去， 其中， 上线用户线路中任意两条线路的导频序列相 互正交； 样本接收单元， 用于接收所述每条上线用户线路 i的接收端 Ri发送的误 差样本， 所述误差样本由所述接收端 Ri根据接收到的导频序列的调制信号获 付；
信道估计单元，用于根据已接收到的所有误差样本及所述上线用户线路的 导频序列计算获得串扰信道估计参数。
9、 根据权利要求 8所述的装置， 其特征在于，
所述序列分配单元，具体用于按照上线用户的上线顺序依次将所述正交训 练导频序列矩阵中的行作为导频序列， 分配至每条上线用户线路 i上； 或者， 按照上线用户的端口号将所述正交训练导频序列矩阵中所述端口号对应的行 作为导频序列， 分配至所述端口号对应的上线用户线路上。
10、根据权利要求 9所述的装置，其特征在于，所述序列分配单元还包括： 第一调整子单元， 用于当存在上线用户线路下线时，将所述正交训练导频 序列矩阵中使用行数最大的线路上的导频序列，更换为所述正交训练导频序列 矩阵中未被使用的行数最小的导频序列；
第二调整子单元， 用于当存在上线用户线路正在激活时，将所述正交训练 导频序列矩阵中未被使用的行作为导频序列分配至正在激活的线路上，并使得 任意两条正在激活的线路上的导频序列之间在最少的列上正交。
11、 根据权利要求 10所述的装置， 其特征在于，
所述第二调整子单元，具体用于将所述正交训练导频序列矩阵中行数较小 的导频序列分配至所述正在激活的线路上，并将未被使用的行数最小的导频序 列作为新的导频序列， 重新分配至已使用所述行数较小的导频序列的线路上。
12、 根据权利要求 8至 11中任意一项所述的装置， 其特征在于， 还包括： 序列选取单元， 用于在所述每条上线用户线路 i的导频序列中， 选取部分 导频序列作为缩短的导频序列， 以使所述发送端 Ti发送所述缩短的导频序列 的调制信号， 其中， 任意两个所述缩短的导频序列之间正交。
13、 根据权利要求 12所述的装置， 其特征在于，
所述序列选取单元， 具体用于在所述每条上线用户线路 i的导频序列中， 截取一段列数连续的导频序列， 作为所述缩短的导频序列； 或者， 在所述每条 上线用户线路的导频序列中，挑选列数不连续的导频序列，作为所述缩短的导 频序列。
14、 根据权利要求 8至 13中任意一项所述的装置， 其特征在于， 所述样 本接收单元包括：
位置确定子单元，用于确定所有接收端发送的误差样本的起始位置及终止 位置，所述起始位置与终止位置之间的所有误差样本所对应的发送端使用的导 频序列之间相互正交；
接收子单元， 用于接收所述起始位置与所述终止位置之间的所有误差样 本。
15、 一种串扰信道估计系统， 其特征在于， 包括矢量化控制实体， 至少两 条上线用户线路， 以及每条上线用户线路 i的发送端 Ti及接收端 Ri,
所述矢量化控制实体，用于根据所述用户线路的规模生成正交训练导频序 列矩阵； 根据所述正交训练导频序列矩阵为每条上线用户线路 i分别分配导频 序列， 其中， 上线用户线路中任意两条线路的导频序列相互正交； 接收所述每 条上线用户线路 i的接收端 Ri发送的误差样本； 根据已接收到的所有误差样 本及所述上线用户线路的导频序列计算获得串扰信道估计参数；
所述发送端 Ti, 用于向所述接收端 Ri发送所述矢量化控制实体为上线用 户线路 i分配的导频序列的调制信号；
所述接收端 Ri, 用于根据接收到的导频序列的调制信号获得误差样本， 并将所述误差样本发送至所述矢量化控制实体。
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017117704A1 (zh) * 2016-01-04 2017-07-13 华为技术有限公司 串扰信道估计的方法、矢量化控制实体vce和接入节点an

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US9287931B2 (en) * 2012-03-30 2016-03-15 Broadcom Corporation Communication system having reduced crosstalk estimation complexity
US8989063B2 (en) * 2012-07-25 2015-03-24 Futurewei Technologies, Inc. Time division multiple access far end crosstalk channel estimation
EP2704331B1 (en) * 2012-08-30 2014-12-24 Alcatel Lucent Method and device for determining a parameter that characterizes a number of spare positions to be used for cancelling the crosstalk of lines joining a digital subscriber line vectoring group
WO2014032260A1 (zh) 2012-08-30 2014-03-06 华为技术有限公司 一种兼容vdsl2传统用户端设备的方法、装置及系统
CN103067316B (zh) * 2012-12-28 2015-11-25 华为技术有限公司 一种串扰信道估计方法、装置和系统
WO2014161191A1 (zh) * 2013-04-03 2014-10-09 华为技术有限公司 探测调制方法、误差反馈方法及相应设备和系统
CN104247358B (zh) * 2013-04-03 2017-11-17 华为技术有限公司 探测调制方法、误差反馈方法及相应设备和系统
US9614660B2 (en) 2013-05-03 2017-04-04 Futurewei Technologies, Inc. Self-synchronizing probe sequence
CN104272819B (zh) * 2013-05-03 2017-12-29 华为技术有限公司 功率控制方法、设备及系统
WO2015039309A1 (zh) * 2013-09-18 2015-03-26 华为技术有限公司 一种线路初始化方法、装置和系统
CN105453501B (zh) * 2014-07-24 2019-02-19 华为技术有限公司 串扰估计方法、装置及系统
CN105790792B (zh) * 2014-12-24 2021-06-15 中兴通讯股份有限公司 一种用户线远端串扰消除矢量计算方法及装置
CN111106850B (zh) * 2018-10-25 2022-07-05 中兴通讯股份有限公司 一种矢量化技术中节省功耗的方法及相关设备
CN112702149B (zh) * 2019-10-22 2022-06-10 华为技术有限公司 一种配置导频序列的方法及装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008024967A2 (en) * 2006-08-25 2008-02-28 Conexant Systems, Inc. Systems and methods for mimo precoding in an xdsl system
CN101155156A (zh) * 2006-09-25 2008-04-02 华为技术有限公司 信道估计方法与装置以及生成导频序列的方法与装置
CN101645754A (zh) * 2008-06-16 2010-02-10 阿尔卡特朗讯公司 用于串扰估计的设备及相关的方法
WO2010093663A1 (en) * 2009-02-12 2010-08-19 Alcatel-Lucent Usa Inc. Simultaneous estimation of multiple channel coefficients using a common probing sequence

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101026606A (zh) * 2006-02-24 2007-08-29 中国科学院上海微系统与信息技术研究所 一种正交导频序列设计方法
EP2219316A1 (en) * 2009-02-13 2010-08-18 Alcatel Lucent Method and apparatus for assigning pilot sequences for further crosstalk evaluation

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2008024967A2 (en) * 2006-08-25 2008-02-28 Conexant Systems, Inc. Systems and methods for mimo precoding in an xdsl system
CN101155156A (zh) * 2006-09-25 2008-04-02 华为技术有限公司 信道估计方法与装置以及生成导频序列的方法与装置
CN101645754A (zh) * 2008-06-16 2010-02-10 阿尔卡特朗讯公司 用于串扰估计的设备及相关的方法
WO2010093663A1 (en) * 2009-02-12 2010-08-19 Alcatel-Lucent Usa Inc. Simultaneous estimation of multiple channel coefficients using a common probing sequence

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2017117704A1 (zh) * 2016-01-04 2017-07-13 华为技术有限公司 串扰信道估计的方法、矢量化控制实体vce和接入节点an

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