Method for crosstalk suppression in logout of subscriber in digital subscriber line system

Abstract

The invention discloses a method for crosstalk suppression in the logout of a subscriber in a digital subscriber line system. The automatic updating of a crosstalk filtering matrix after the logout of the subscriber is realized by fully utilizing conventional channels and the information of a crosstalk filter which is the crosstalk filtering matrix before the logout of the subscriber, and crosstalk interference in a transmitted signal transmitted by the subscriber in a transmission process is suppressed by utilizing the updated crosstalk filtering matrix, thereby completely suppressing the crosstalk interference under a new interference environment after the logout of the subscriber and further improving the transmission performance of the channels. Moreover, by the method provided by the invention, the repeated use of a conventional zero-forcing algorithm for suppressing the crosstalk interference under the new interference environment after the logout of the subscriber is avoided, so computational complexity is greatly reduced.

Description

technical field [0001] The invention relates to a crosstalk suppression method, in particular to a crosstalk suppression method when a user goes offline in a digital subscriber line system. Background technique [0002] The invention of the telegraph and the telephone ushered in a new era of communication technology. With the rapid development of telephone services, the Public Switched Telephone Network (PSTN) has spread all over the world and has become an important part of the communication network. Among many wide area network technologies, the cost of interconnecting communication through PSTN is the lowest, and the network resource utilization rate of PSTN is also relatively low. In order to make full use of the spectrum resources of the PSTN, Bellcore invented the digital subscriber line (DSL, Digital Subscribe Line) access technology, expanding the development and application space of the PSTN. [0003] After years of development of DSL technology, the transmission r...

AI Technical Summary

Problems solved by technology

At present, the crosstalk suppression algorithm in the uplink transmission direction is mainly concentrated in the frequency domain, and the representative algorithm mainly includes the zero-forcing (ZF, Zero-forcing) algorithm, which has the advantage of completely suppressing crosstalk, thereby improving the transmission performance of the channel. Greatly improved, but the computational complexity of the zero-forcing algorithm has a cubic relationship with the number of users, and the number of subcarriers in the VDSL2 system is large, so the zero-forcing algorithm will generate huge computational complexity

The existing research on the zero-forcing algorithm only discusses the situation that the user remains unchanged in the access network, and there is no report on the situation that the user changes. However, in the actual system, the user may go online and offline at any time, resulting in serial If the sound environment changes, it is necessary to suppress the crosstalk interference in the new interference environment in time, and the repeated use of the zero-forcing algorithm will inevitably generate a huge amount of calculation, resulting in a slow system response

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