A positioning satellite for a constellation of satellites of a radio navigation satellite system includes transmitter means adapted to transmit operational signals intended to enable the determination of positions of radio navigation receivers, receiver means adapted to receive at least some of the operational signals transmitted by positioning satellites of the constellation that are in view and processor means adapted to interrupt transmission of the operational signals by the transmitter means at selected times for a selected duration and to analyze during each transmission interruption at least some of the operational signals received by the receiver means during at least a portion of the selected duration, for example to verify the waveform thereof and/or to determine pseudodistances.