In an embodiment, a method for determining the phase shift between a first signal and a second signal includes: delivering the first signal to a first input of a 90° hybrid coupler; delivering the second signal to a second input of the 90° hybrid coupler; determining a first piece of information relating to a power of a first output signal delivered to a first output of the 90° hybrid coupler; determining a second piece of information relating to a power of a second output signal delivered to a second output of the coupler; and adjusting the phase of the second signal until obtaining a calibrated phase for which the first piece of information is substantially equal to the second piece of information, wherein the first and second signals have identical frequencies, and wherein the phase shift between the first signal and the second signal is equal to the calibrated phase.