Noise reduction in cable return paths

摘要

A method of reducing noise and ingress in cable return paths is disclosed in which the return frequency spectrum is divided into two regions; one frequency region being for transmissions from in-home devices such as television settops and personal computers, and another frequency region being for transmissions from communications devices called coaxial termination units located between the drop cable and the home coaxial wiring. By locating blocking filters between the drop cable and home coaxial wiring, undesirable signals emanating in the home in the second part of the return spectrum are prevented from entering the cable return system. The location of the blocking filter reduces the noise in the second part of the return spectrum substantially and allows the establishment of reliable telecommunications services on the cable return in such second part of the return spectrum. The blocking filters can be incorporated into the coaxial termination unit and the bandwidth of such filters varied from the head-end to allow more or less bandwidth to be used by in-home devices.