METHOD AND SYSTEM FOR PREESTIMATING MAXIMUM BANDWIDTH OF SUBSCRIBER LINE IN DIGITAL SUBSCRIBER LOOP

摘要

A method and a device for pre-estimating the maximum bandwidth of a subscriber line in the digital subscriber loop. The method comprises: obtaining independent crosstalk noises according to the line length of the measured subscriber line, the line transfer equation, and the power spectral density of each frequency signal in the frequency band of a Digital Subscriber loop (DSL) of other subscriber lines in the line pair where the measured subscriber line is located; obtaining total crosstalk noise with time domain superposition; according to the DSL band used by the measured subscriber line, selecting the total crosstalk noise subjected by each frequency signal in that band as well as the line attenuation; using the power spectral density of each frequency signal in that band to obtain the signal-to-noise ratio of each frequency signal in that band; and obtaining the maximum bandwidth according to the frequency domain form of the Shannon's law. The solution can exactly pre-estimate the maximum bandwidth of the subscriber line before the DSL service is actually launched.