1. A circuit for monitoring a channel quality comprising: a reference level generator providing a reference window representing a plurality of reference levels; a comparator coupled to said reference level generator to produce an output signal based upon said reference window and a channel signal; a counter coupled to said comparator to track the number of signals from said channel that fall within said reference window; a second reference generator providing a second reference window representing said plurality of reference levels; a second comparator coupled to said second reference generator to produce a second output signal based upon said second reference window and said channel signal, said comparator coupled to said counter; and a summing circuit with input terminals coupled to said reference generators and providing outputs to said counter.