Overvoltage Coarse protectors

Family : Surge arrester
Category : Coaxial cables SPD

Protection of the radiocommunication equipment

 Radiocommunication systems, connected to antennae, are especially exposed to lightning phenomena, the maximum risk being a direct strike on the antenna pole.

Equipment, as GSM/UMTS or TETRA base stations, must consider this risk in order to insure a relevant service continuity.

RF surge protection technology

The gas discharge tube (GDT) is the only surge protection component usable on very high frequency transmission (several GHz) due to its very low capacitance. In a coaxial surge protector, the GDT is connected in parallel between the central conductor and the external shield ; when its sparkover

voltage is reached, during an overvoltage, the line is briefly practically shorted (arc voltage). The sparkover voltage depends on the rise front of the overvoltage. The higher the dV/dt of the overvoltage, the higher the sparkover voltage of the surge protector.

When the overvoltage disappears, the gas discharge tube returns to its original condition of high insulation and is ready to operate again. The gas tube is removable, making maintenance rapid in the end-of-life case.

The greater advantage of this technology is its very wide bandwidth : from DC (so, compatible with DC voltage injection) to several GHz.