Abstract: The present disclosure relates to the field of synchronising a radio frequency (RF) communication system based on the repeated transmission of data at the transmitter and the use of a method for the time synchronous averaging of this data at the receiver. The proposed communication technique uses the fact that the data signal is periodically repeated, without requiring the use of synchronisation data external to the data to be communicated. It enables phase and frequency synchronisation to be maintained when the received signals are very noisy, and even when they have a signal-to-noise ratio of less than 1 or even a negative signal-to-noise ratio (in dB). A significant improvement in the processing gain of the method for time synchronous averaging is advantageously achieved.