The present document specifies technical characteristics and methods of measurements for the following equipment types (which are parts of a Mobile Communication On Board Aircraft system): 1) The Onboard Base Transceiver Station (OBTS) supporting GSM and/or UMTS, and/or LTE communication protocols including specific functions for restricting the transmit power of the MSs or UEs, associated with the OBTS. 2) The Network Control Unit (NCU) preventing direct connection of the onboard mobile terminals with mobile networks on the ground by raising the noise floor in the cabin. The OBTSs are capable of operating in all or any part of the frequency bands given in table 1-1.