Patent ID: 7653161

Claim:
A method of controlling operation of a communications system for receiving and processing an input communication signal to produce an output communication signal, comprising: selecting a first noise margin relating to an external noise level present in the input communication signal, wherein the first noise margin is an amount of external noise increase that the communications system can tolerate while still insuring a data transport with a bit error rate less than a required bit error rate; selecting a second noise margin relating to an internal noise level generated by the communications system, wherein the second noise margin is a function of the first noise margin, and wherein a value of the second noise margin is less than a value of the first noise margin; calculating a virtual noise-to-signal ratio based on an external noise-to-signal ratio NSRe, an internal noise-to-signal ratio NSRi, said first noise margin, and said second noise margin; and controlling at least one operating parameter of the communications system to maintain said virtual noise-to-signal ratio at a predetermined margin above a required noise-to-signal ratio.