Huawei Technologies Co., Limited

Future Wei Technologies, Inc.

Jianping Tu

Zhong Pan

Xiang Wang

Jie Lv

Haixiang Liang

Liming Fang

Jie Liu

Hui Yin

Fanglin Sun

Cao Shi

Chin Ngek Hung

Dawei Sun

Huishen Dong

Jinxiong Lv

Jinxiong Lu

Lang Zhou

Yujie He

Yahong Gao

Embodiments of the present invention provide a signal processing method, including: dividing a frequency band used to send a downlink synchronization symbol into at least two parts of frequency bands that do not overlap, where the two parts of frequency bands are a first frequency band and a second frequency band; alternately allocating frequencies in the first frequency band to a probe tone and a flag tone; and allocating all frequencies in the second frequency band to a probe tone; and modulating a downlink pilot sequence to probe tones in the first frequency band and the second frequency band, and sending the downlink pilot sequence to a peer device. The embodiments of the present invention further provide a signal processing apparatus and a network system.

Signal processing method, apparatus, and system

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

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

A digital subscriber line (DSL) network device for coupling to DSL communication lines, the network device comprising: multiplexing circuitry that transmits signals to vector-compliant consumer premises equipment (CPE) and legacy CPE via the DSL communication lines; and processing circuitry configured to: initiate transmission of a predetermined set of orthogonal pilot sequences to a plurality of vector-compliant CPEs; initiate transmission of data symbols corresponding to the set of orthogonal pilot sequences to one or more legacy CPEs; pre-process line errors of a victim vector-compliant CPE to remove far-end crosstalk due to the vector compliant disturber lines and perform the same pre-processing for the transmitted data symbols; determine far-end channel crosstalk information using a correlation of the pre-processed line errors and the pre-processed transmitted data symbols; and reduce far-end channel crosstalk of the victim vector-compliant CPE using the determined far-end channel crosstalk information.

Crosstalk channel estimation for legacy CPE

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

A method for canceling crosstalk between lines in a DSL system is presented. The method includes obtaining an upstream signal that is sent by corresponding customer premises equipment (CPE) and that is received by each central office (CO), forming an upstream signal sequence including upstream signals of all COs, obtaining a downstream signal that is sent by each CO to the CPE corresponding to each CO, and forming a downstream signal sequence including downstream signals of all the COs; performing FEXT cancellation processing on the upstream signal sequence to obtain a first signal sequence, and processing the downstream signal sequence to determine NEXT signals in the upstream signals of all the COs; and performing NEXT cancellation processing on the first signal sequence using the determined NEXT signals, to obtain a second signal sequence, and sending upstream signals in the second signal sequence to all the COs.

Method, device, and system for canceling crosstalk between lines in DSL system

A method comprising allocating one or more detection tones of a sync symbol for crosstalk-free feedback data estimation, wherein the one or more detection tones are a quiet signal; transmitting the one or more detection tones to a computing device, receiving the crosstalk-free feedback data from the computing device, wherein the crosstalk-free feedback data comprises data associated with a background noise detected during the detection tones; determining an optimized PSD based at least in part on the crosstalk-free feedback data; and adjusting a transmission PSD of a plurality of tones based at least in part on the optimized PSD.

Power spectrum density optimization

A crosstalk processing method, an apparatus, and a system comprise a transceiver of a line that generates, respectively according to pilot sequences allocated by a vectoring control entity, pilot training signals that are within different spectral ranges and that satisfy a preset relationship with a pilot training signal of another line such that a receiver of the line can determine sample errors respectively according to the different pilot training signals. A vectoring control entity then determines crosstalk channel coefficients from the other line into an inband spectrum and an out-of-band spectrum of the line, and performs precoding processing on a to-be-sent data signal of the line to eliminate impact of crosstalk from the other line to the inband and out-of-band spectrums of the line.

Crosstalk estimation method, apparatus, and system

The present invention provides a method and an apparatus for training a Vector coefficient of a vectored digital subscriber line, where the method includes: after a handshake phase is executed for a joining line, calculating, by using a pilot estimation method, an initial precoding coefficient and an initial cancellation coefficient that represent interference from the joining line to a normal working line; and after a channel discovery phase is executed for the joining line, compensating the initial precoding coefficient and the initial cancellation coefficient by using a compensation factor, to obtain a precoding coefficient and a cancellation coefficient that represent the interference from the joining line to the normal working line, wherein the compensation factor is obtained according to a signal power change or a signal phase change of the joining line. The present invention improves efficiency of Vector coefficient training.

Method and apparatus for training vector coefficient of vectored digital subscriber line

Embodiments of the present invention relate to a method and an apparatus for sending a single-ended loop testing SELT measurement signal, and a control device. The method for sending a SELT measurement signal includes: aligning a synchronization symbol of a digital subscriber line on which a SELT diagnosis needs to be performed with a synchronization symbol of at least one DSL line for data transmission, where the synchronization symbol of the digital subscriber line on which a SELT diagnosis needs to be performed and the synchronization symbol of the at least one digital subscriber line for data transmission are uplink or downlink synchronization symbols; and carrying a SELT measurement signal over the aligned synchronization symbol of the DSL line on which a SELT diagnosis needs to be performed, where the SELT measurement signal is used to detect transmission quality or a line fault of the DSL line.

Method and apparatus for sending SELT measurement signal, and control device

Embodiments of the present invention provide a method and an apparatus for analyzing crosstalk between lines, where the method includes: performing frequency spectrum notching on a specific frequency band of lines of which the number is a first number among multiple lines, collecting a first group of state performance parameters of each line of lines of which the number is a second number among the multiple lines; canceling frequency spectrum notching on the specific frequency band of the to-be-analyzed line, collecting a second group of state performance parameters of each line of the lines of which the number is the second number; and determining, according to the first and second groups of state performance parameters, crosstalk of each line of the lines of which the number is the second number into the to-be-analyzed line on the specific frequency band.

Method and apparatus for analyzing crosstalk between lines

The present invention provides a method, an apparatus, and a system for reducing digital subscriber line interference. The method includes identifying at least one legacy digital subscriber line in a digital subscriber line DSL legacy line set, obtaining a target power spectral density mask value of the legacy digital subscriber line, and reducing power spectral density of a transmit signal on the legacy digital subscriber line according to the target power spectral density mask value.

Method, apparatus, and system for reducing digital subscriber line interference

An apparatus for synchronizing a plurality of digital subscriber line access multiplexers (DSLAMs) comprising a reference clock configured to generate a reference clock signal, and an interface configured to transmit the reference clock signal to the DSLAMs, wherein each of the DSLAMs is configured to align its system clock with the reference clock.

Node level vectoring synchronization

A method, an apparatus, and a system for reducing line-to-line crosstalk during transmission of a digital subscriber line service are disclosed, where the method includes: before a service is provisioned, obtaining, by a service provider according to a service transmission rate and a topology scenario parameter that are provided by a service receiving side device, a power spectral density of a line in a process of receiving a service by the service receiving side device; and provisioning, by the service provider, a service for the service receiving side device according to the power spectral density.

Method, apparatus, and system for reducing line-to-line crosstalk during transmission of digital subscriber line service

A method, system, and device for power optimization based on Digital Subscriber Line (DSL) are provided. The method includes the following steps. Service information of a subscriber is collected, and physical layer target parameters are obtained according to Quality of Experience (QoE) parameters corresponding to the service information. Line running information of the subscriber is received. The physical layer target parameters and the line running information are used as input parameters of a power optimization algorithm, and an optimized power spectrum is obtained through the power optimization algorithm. Therefore, a DSL network is optimized according to the QoE, and subscriber's experience is improved. Moreover, a least power method is adopted to optimize a transmit power spectrum, and the total power consumption and crosstalk between different DSL signals are reduced while meeting the QoE, so that the signal transmission of the system is stable, and the service transmission quality is improved.

Method, system, and device for power optimization based on digital subscriber line

A method, a device and a system for Upstream Power Back-Off (UPBO) in a Digital Subscriber Line (DSL) are provided. The method includes: collecting subscriber line information (S); determining a reference line length according to the subscriber line information (S); obtaining UPBO parameters of each upstream band of each subscriber line according to the determined reference line length (S), where the UPBO parameters include an original point parameter, a back-off slope parameter, and a maximal close frequency point (UPBOFMAX) corresponding to the band; and executing an UPBO process on the band of the corresponding subscriber line below the UPBOFMAX according to the UPBO parameters (S). Thus, the stability of longer lines can be ensured, an upstream rate of short lines is maximally increased, and the existing UPBO mode is fully compatible.

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Shenzhen, China

Jianping Tu