Patent ID: 8000254

Claim:
A method for determining a dominant impairment on an impaired communication channel, comprising the steps of: measuring initial total power loading which is equal to total power of RF energy present within a bandwidth of interest on a test channel; selecting and remotely instructing a network element to transmit a first test signal on the test channel at initial total power loading; monitoring the first test signal at a headend of the test channel and measuring at the headend at least one of modulation error ratio (MER 0 ), signal-to-noise ratio (SNR 0 ), packet error rate (PER 0 ), and bit error rate (BER 0 ); after said above steps, remotely instructing the network element to transmit a second test signal on the test channel at a different power level such that initial total power loading is adjusted by a pre-determined amount (X); monitoring the second signal at the headend of the test channel and measuring at the headend at least one of modulation error ratio (MER 1 ), signal-to-noise ratio (SNR 1 ), packet error rate (PER 1 ), and bit error rate (BER 1 ); and comparing the measurement taken for the first test signal to the measurement taken for the second test signal and determining whether the measurement degraded, improved, or stayed substantially equal.