A method for demodulating a signal in a receiver comprising at least two antennas (4, 6) each receiving a signal (s 1; s 2) transmitted through an associated radio propagation channel, the received signals (s 1; s 2) corresponding to a same emitted signal (s) comprising frames of time- and frequency-divided symbols in which some symbols, called pilot symbols, are known to the receiver, said method comprising the steps of: - noise whitening to form two combined signals (c 1; c 2) the noises of which are independent; - normalising the noises of the combined signals (c 1; c 2) to form two signals (r'; r") the noises of which are independent and with equal average norms; - a signal demodulation step at a maximum signal to noise ratio combination of the two signals with independent noise and equal average norms (r'; r") characterised in that the first noise whitening step to form both combined signals (c 1; c 2) comprises sub-steps of: - weighting each of the received signals (s 1; s 2) with respective first weighting vectors ( w 1; w 2) associated with a respective antenna (4, 6) of the receiver, the signal associated with the first antenna being weighted by a vector wi and the signal associated with the second antenna being weighted by a vector w 2, - combining the received weighted signals to form a first combined signal (c 1), - weighting a reference signal (d) comprising said pilot symbols with another weighting vector (w d), - comparing the first combined signal (c 1) and the weighted reference signal to form an error (ε), and - determining the weighting vectors ( w 1; w 2) using a maximum a posteriori (MAP 1) criterion by maximising the probability of making said weighting vectors conditionally to the error obtained, - weighting each received signal (s 1, s 2) with second weighting vectors ( w* 2, - w* 1), the signal received on the first antenna being weighted by the conjugate of the complex vector w 2 and the signal received on the second antenna being weighted by the opposite of the conjugate of the complex vector wi, - combining the received signals (s 1, s 2) weighted by the second weighting vectors to form a second combined signal (c 2). - noise whitening to form two combined signals (c 1; c 2) the noises of which are independent; - normalising the noises of the combined signals (c 1; c 2) to form two signals (r'; r") the noises of which are independent and with equal average norms; - a signal demodulation step at a maximum signal to noise ratio combination of the two signals with independent noise and equal average norms (r'; r") - weighting each of the received signals (s 1; s 2) with respective first weighting vectors ( w 1; w 2) associated with a respective antenna (4, 6) of the receiver, the signal associated with the first antenna being weighted by a vector wi and the signal associated with the second antenna being weighted by a vector w 2, - combining the received weighted signals to form a first combined signal (c 1), - weighting a reference signal (d) comprising said pilot symbols with another weighting vector (w d), - comparing the first combined signal (c 1) and the weighted reference signal to form an error (ε), and - determining the weighting vectors ( w 1; w 2) using a maximum a posteriori (MAP 1) criterion by maximising the probability of making said weighting vectors conditionally to the error obtained, - weighting each received signal (s 1, s 2) with second weighting vectors ( w* 2, - w* 1), the signal received on the first antenna being weighted by the conjugate of the complex vector w 2 and the signal received on the second antenna being weighted by the opposite of the conjugate of the complex vector wi, - combining the received signals (s 1, s 2) weighted by the second weighting vectors to form a second combined signal (c 2).