In a report by Space News, it has been revealed that the European Space Agency (ESA) has cut signal power by 1.5dB from the four initial Galileo navigation system satellites launched to date. The move was done as a precautionary measure after three of the satellites were affected by anomalies.
In Mid-2013, Galileo IOV FM-3 was affected by a 2dB power drop on one of its signals. In May-June 2014, there was a similar if apparently unrelated signal power loss on Galileo IOV FM-4. Meantime Galileo IOV PFM/FM-1 has suffered a failure on the satellite’s solid-state power amplifier (SSPA). Galileo IOV FM-2 has not yet been affected by any anomaly. The satellites which were launched in October 2011 were built by Astrium (now Airbus Defence and Space).
ESA says that the anomalies to the orbiting satellites will not affect the flights of the main Galileo constellation which are Galileo FOC satellites built by the OHB/SSTL consortium.