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ADSL frequency spectrum. 

ADSL frequency spectrum. 

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Article
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The provision of broad-band services based on either the Internet or the asynchronous transfer mode (ATM) technique requires a new generation of access networks. In the short term, solutions such as x-digital subscriber line (DSL) and hybrid fiber coaxial (HFC), allowing the reuse of existing infrastructures look very promising. For the longer term...

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Context 1
... ADSL technique is an extension of HDSL. Unlike HDSL, ADSL deals with asymmetrical traffic for which the downstream flow is assumed to be greater than the upstream one [7], [10]. This is typically the case for multimedia interactive services (VoD, teleshopping, entertainment, etc.) for which the end user accesses a server through the public network. The end user sends short request messages to the server. Depending on the required service, the server answers these requests with longer messages under the form of data files, digitized sounds, digitized fixed images, or video sequences. ADSL is a cost-effective way to offer multimedia services to the end user via the existing local loops. Fig. 7 shows how the local-loop bandwidth is used in ...

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Citations

... And it increases connection speeds for the remote users from the telephone exchange. It extends the broadband area from 3.5 to 5.5 km [17]. ...
... The types of xDSL technology are compared with the specified features and presented in table form in Annex-2 [2], [3], [14], [17]- [20]. The features used when making comparisons are important for these technologies. ...
... It will be integrated with many applications in the future to make it even more useful and productive. [2], [3], [14], [17]- [20] Types of xDSL Data path download/upload ...
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... Such channels have been shown to occur if, e.g., DMT is used as modulation scheme [9], [10]. Note that DMT is currently employed in several xDSL standards [19]. We derive capacity expressions for two cases: 1) we assume that the knowledge of the complementary covariance matrix is taken into account (both at transmitter and receiver); and 2) we assume that it is erroneously believed-i.e., that the transceiver is designed assuming-that the noise has a vanishing complementary covariance matrix, so that the information contained in the complementary covariance matrix is ignored. ...
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