It helps to assure that the BTS is operating according to the specifications and it has to do with activities to reduce the fault probability. Deploying these activities in the recommended periods of time will help to assure an operation free of faults and shorter periods of down time when problems do occur. The routines should be done based on a schedule basis and consists on a physical check and monitoring of the elements that integrate the BTS. Even though preventive maintenance can detect potential sources of fault before they affect the service.
This is done is response to a fault or a potential source of fault in a BTS. This kind of maintenance refers to the detection of faulty units while they are in service. The procedures to solve the fault, without caring if this it has been diagnosed as part of a preventive or corrective maintenance, they are the same once the cause of the fault has been identified.
It is related with activities to improve BTS performance, without caring if the BTS is operating correctly. This maintenance includes technical support in site and BTS commissioning.