Digital transmission over in-home coaxial wiring

The wiring of a customer's premises network (CPN) may be the weakest link in the end-to-end transport of residential broadband digital services such as digital video. Detailed knowledge of how such premises wiring will affect digital service delivery is critical to the cost-effective deployment and robust operation of digital technologies. This paper reports selected results from a series of experimental and analytical studies of coaxial-cable premises-wiring impairments for digital broadband signals. The investigations included return loss, isolation and attenuation measurements of a wide variety of components, as well as measurements and simulations of bit-error-rate performance for several inside-wiring test-bed configurations. The components showed a broader range of performance, and in some cases considerably worse performance, than indicated in previous studies. The premises wiring generated signal reflections which can severely degrade digital transmission. Some reflections can cause destructive interference that effectively decreases the received signal power by 10 dB more than the nominal attenuation, and this decrease is not mitigated by set-top or cable-modem adaptive equalization.