System and method for dynamically calibrating one or more radiofrequency channels of a satellite payload

A method for dynamic calibration of a radiofrequency circuit of a satellite payload,

• the radiofrequency circuit comprising a first radiofrequency chain to be calibrated for amplification and for filtering with or without transposition to a predetermined transposition frequency of a first input signal made up of the temporal sum of a second calibration signal and of a third useful input signal,
• the first radiofrequency chain to be calibrated on a useful chain band lying between upstream a first upstream port for receiving the first input signal and downstream a first downstream port for providing a first output signal, the first output signal being the frequential and temporal response of the first radiofrequency chain to be calibrated to the first input signal;
• the method of dynamic calibration comprising the steps wherein:
• in a first step, an injection device injects the second calibration signal whose waveform is predetermined upstream of the first radiofrequency chain to be calibrated, the second calibration signal being injected directly in digital form or indirectly in analogue form through a second analogue injection chain on the basis of a reference calibration signal;
• and then
• in a second step, a compensation device compensates, on the useful frequency band of the first chain to be calibrated, amplitude-wise and phase-wise disparities caused by the first chain to be calibrated, with the aid of a compensation filter, disposed upstream or downstream of the first radiofrequency chain to be calibrated, the compensation being carried out on the basis of measurements of a fourth signal observed downstream of the first radiofrequency chain to be calibrated and of the compensation filter, or directly downstream of the first chain to be calibrated;
• and
• the method of dynamic calibration comprising a third step, executed after the first step, in the course of which a temporal erasure device temporally erases the calibration signal injected with the aid of an analogue subtracter or digital subtracter, connected downstream of the first chain to be calibrated.