Coaxial cabies with physically-foamed PE insulation is the fourth generation of CATV cble,which possess more excellent high frequency properties than CATV cables with solid PE,chemically-foamed PE insulation and longitu dinal aperture PE.The products have the characteristics of low a ttenuation,good coherence and not liabie to dampetc.,and they are broadly used in telecommunication and Wide Band of tele-broadcasting system.