ABSTRACT -- This paper analyses the performances of data communication on the return path of the HFC Network, following the DOCSIS (Data Over Cable Service Interface Specifications) and IEEE 802.14 standards. Three methods of modulation; BPSK QPSK and 16 QAM are analyzed under impulsive noise environment with reference to class-A impulse noise model. The result indicates the relationship of each modulation methods in term of BER via CNR.

KEYWORDS -- Hybrid Fiber Coaxial Network , Return Path , Impulsive Noise , Carrier to Noise Ratio