Antenna cables are coaxial cables that connect the antenna to the antenna amplifier or directly to the receiving device, set-top box, receiver or tuner. Antenna cables are used in home and community antenna systems and must transmit the entire reception frequency ranges for radio and television.
These range over FM broadcasting and the various frequency bands for the VHF and UHF range up to 862 MHz. In addition, the frequency range for satellite reception must be taken into account, and this extends up to 2.15 GHz. This means that antenna cables must be designed for the frequency range up to 3 GHz.
Since the distances between antenna or LNB converter and receiving equipment may well be between 10 m and 100 m, low attenuation is a requirement for antenna cables. As further requirements, the impedance of the antenna cable must be adapted to the footpoint resistance of the antenna and the antenna cable must not pick up any external signals if possible.
As far as attenuation is concerned, it is kept as low as possible by using thicker high-frequency cables with silver-plated inner conductors and silver-plated shielding. Therefore, good antenna cables have attenuation values of about 12 dB/100 m to 17 dB/100 m at 450 MHz and 30 dB/100 m to 40 dB/100 m at 2.5 GHz. As far as impedance is concerned, this is usually 75 ohms and thus matched to the antenna impedance of a dipole antenna, and for the shielding, multiple shielding with foil and braided shielding is used, in some antenna cables also multi-layered as foil-braided-foil-braided. This contributes significantly to improving the shielding effectiveness. Good antenna cables have a shielding effectiveness of 120 dB up to 2 GHz and are equally suitable for analog TV and digital TV.