Relationship between physical and higher layer errors in HFC communication network

We studied the impact of the channel noise, especially additive white Gaussian noise (AWGN) over the broadband HFC access network. The modulation scheme of this digital communication channel is QPSK. We have derived a network system error model for the HFC communication channel, which yields a relationship between bit error rate and signal to noise ratio (SNR) in a noisy communication channel. We measured in the laboratory packet loss as a function of SNR for this HFC communication network, and derived an empirical relationship between the physical layer bit error rate (BER) and the higher layer packet loss. The results of this study would be beneficial in network management of broadband HFC access network.