A measurement and control system for use in performing a medical procedure is provided. The medical procedure can employ an energy source, the energy source can be connected to an energy delivering device via a transmission line. The system includes a measurement system, the measurement system is configured to sample an output signal generated by the energy source. The system includes a control system, which includes a calibration unit. The calibration unit is configured to generate a calibration signal. The calibration signal has a magnitude and phase, wherein the magnitude and phase is representative of the output signal and the transmission line loss information. The system also includes a control unit. The control unit is configured to receive the calibration signal and adjust the energy source as needed.