Mobile phone base stations are often placed in exposed elevated locations for the maximum possible broadcast coverage. Often this unintentionally results in the erection of an ideally positioned lightning conductor. Protection of all mobile base stations against inevitable direct or nearby lightning strikes is essential. Failure to design robust protection leads to expensive repairs in these exposed and often difficult to reach areas. It is common for antenna masts to see voltages of 250 kV from top to bottom during a direct lightning strike. With appropriate protection these events can be survivable.
Protection is required on all services into and out of the base station equipment; failure to protect just one port can lead to extensive equipment damage. Ports commonly found are coaxial or waveguide for RF transmission, as well as multiple control lines which are used to monitor and control antenna status, etc. To add further complication, the distance between the tower and the transmitters can be up to 30 meters, adding Ground Potential Rise (GPR) as an additional threat. Following are three common interface ports which are exposed to significant threat from lightning and resultant GPR. The unique Bourns® TBU® High-Speed Protector (HSP) technology can prevent the high currents caused by lightning events from reaching sensitive electronic circuits, resulting in greater system reliability and ultimately, lifetime cost savings.