In this study, the properties of the up-stream accumulation noise have been explored by measuring the up-stream carrier-to-noise ratio (CNR) value in the head-end. An experimental two-way CATV network system has been constructed: down-stream bandwidth is 50 ~ 750 MHz, and up-stream bandwidth is 5 ~ 42 MHz. Experimental results have shown that the up-stream accumulation noise is time dependent, resulting in the Internet over fiber optical CATV systems operating unstable. And further, not all up-stream frequencies are available for two-way communication services. The frequency above 25 MHz is more suitable for adding twoway services.
All Science Journal Classification (ASJC) codes