METHOD FOR IMPROVING xDSL TRANSMISSION CHARACTERISTICS AND xDSL TRANSMISSION CHARACTERISTICS MEASURING SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide a means capable of easily executing characteristic confirmation of a channel in an xDSL for rapid data communicating by utilizing a telephone line by an existing copper wire. SOLUTION: A voltage measuring unit 13 is connected via an MDF(Main Distribution Frame) 11 and a test lead-in relay 12 connected to subscriber's side line wire terminals T and R. The unit 13 has an amplifying function capable of regulating a receiving signal level, and is connected to an A-D converter 14 for A-D converting. A controller 16 connected to the converter 14 fast Fourier transforms the digital output signal obtained by a prescribed sampling frequency by the converter 14 at an FFT unit 15. The obtained noise spectrum is compared with a template for deciding a noise level applied by a weight in an object frequency, and whether the channel can be used or not is decided.