Patent ID: 8655992

Claim:
In a communication system comprising an adaptive transmission channel, a method comprising: measuring and determining a total amount of user data transmitted over the adaptive transmission channel during a predefined measurement interval, and calculating a corresponding user data bit rate; determining sub-amounts of user data out of the total amount of user data that have been transmitted at each of a plurality of modulation and coding combinations used for the adaptive transmission channel during said predefined measurement interval; multiplying each sub-amount of user data by a predefined spectral efficiency figure corresponding to the modulation and coding combination used for modulating that sub-amount of user data; summing all said multiplication products and dividing the result by said total amount of user data transmitted to produce an estimated average spectral efficiency figure for the user data transmitted during the predefined interval; calculating a null packet bit rate using the estimated average spectral efficiency figure; and calculating an available bit rate as the sum of the calculated user data bit rate and the calculated null packet bit rate.