CHARACTERIZING A DOWNSTREAM PATH OF A CABLE NETWORK

摘要

Downstream channel parameters of a cable network are displayed in graphical form as a function of the channel number or center frequency. Such parameters, including digital channel demodulation parameters, may be plotted concurrently as frequency spectra, revealing frequency signatures of particular network impairments. Frequency spectra of MER, BER, IUC, carrier level, and in-band spectral response may be plotted concurrently in various combinations, providing a concise summary view of a condition of a downstream path at a particular location in the network.

主权项

1. A method of characterizing a downstream path of a cable network, the downstream path including a plurality of downstream channels, each channel having a channel number or center frequency, the method comprising:
(a) causing a tuner to tune in sequence to each one of the plurality of downstream channels; (b) causing a processor to demodulate each one of the plurality of downstream channels and to determine a value of a first demodulation parameter for each one of the plurality of downstream channels tuned to in step (a); and (c) causing a display to display the first demodulation parameter on a display in graphical form as a function of the channel number or center frequency.