Method to mitigate effects of ISDN off/on transitions in ADSL

The present invention provides for a method and apparatus for allocating data to subchannels used for ADSL transmission over a communication link which supports further system transmissions. An expected interference impact from the further system transmissions is estimated for the ADSL subchannels....

Ausführliche Beschreibung

Gespeichert in:

Bibliographische Detailangaben
Hauptverfasser:	WIESE BRIAN R, AGAH MICHAEL D, JACOBSEN KRISTA S
Format:	Patent
Sprache:	eng
Schlagworte:	ELECTRIC COMMUNICATION TECHNIQUE ELECTRICITY JAMMING OF COMMUNICATION SECRET COMMUNICATION TELEPHONIC COMMUNICATION TRANSMISSION TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHICCOMMUNICATION
Online-Zugang:	Volltext bestellen
Tags:	Tag hinzufügen Keine Tags, Fügen Sie den ersten Tag hinzu!

Beschreibung
Zusammenfassung:	The present invention provides for a method and apparatus for allocating data to subchannels used for ADSL transmission over a communication link which supports further system transmissions. An expected interference impact from the further system transmissions is estimated for the ADSL subchannels. Signal-to-noise ratios (SNRs) for the subchannels are determined for bit loading by an estimator ( 220 ). In one embodiment, actual noise associated with the communication link is used at initialization to determine a SNR which is subsequently modified by an adjusting unit ( 205 ) prior to bit loading responsive to the estimated interference impact. In another embodiment, a virtual noise signal, indicative of the estimated interference impact and generated by a noise signal generator ( 235 ), is summed with the actual noise prior to determining a SNR for bit loading. Prior to transmitting, the data is allocated to the subchannels by a bit loader ( 210 ) based on respective SNRs modified responsive the estimated interference impact.