Patent attributes
A method for designing an equalizer and tracking performance for upstream PCM in a digital communications network is described. The invention optimizes upstream data rate rates for data transmissions in a network between a client modem a server modem. During training, the upstream channel impulse response is identified compensating for any robbed bit signalling. The upstream transmit equalizer is computed in closed form based on the identified channel. An equalizer in the receiver is also used to track timing and channel variations. The invention approximates bit error rate performance by looking for code violations in the trellis code decoder and tracking their frequency. The bit error rate is used to determine if the current modem parameters need to be re-designed.
