A system for positioning at least one mobile receiver, the system comprising, in addition to the mobile, at least two stationary transmitter bases (4, 4A, 4B), each transmitter base (4, 4A, 4B) being configured to transmit radio frequency signals (S1 A, S1 B, s dA, s dB, s rA, s rB), the transmitter bases (4, 4A, 4B) being synchronized to each other to transmit their respective signals, the mobile receiver being configured to receive and process said radio frequency signals (s dA, s dB, s rA, s rB) and to deduce therefrom its position by calculating the time-of-flight difference(s) between the mobile receiver and the transmitter bases (4, 4A, 4B), the mobile receiver comprising means for storing position data of the stationary transmitter bases (4, 4A, 4B), characterized in that each transmitter base (4, 4A, 4B) is configured to transmit a sum (S1 A, S1 B) of at least two unmodulated pure carrier signals of different frequencies, each pure carrier signal being in the form of an unmodulated continuous wave, which is preferably sinusoidal; and in that the mobile receiver further comprises: • means for measuring, for each given signal frequency and for each respective transmitter base (4A, 4B), the phase of the signal consisting of the various signals (s dA, s rA, s dB, s rB) coming from said base and having said frequency; and • computing means connected to the measuring means and to the storage means, and configured to: o apply, for each transmitter base (4A, 4B), a Fourier transform to a signal consisting of the various measured phases of the radio frequency signals coming from said base (4A, 4B); o determine, for each transmitter base (4A, 4B), from the Fourier transform computed for said base, a time-of-flight between the mobile receiver and said base (4A, 4B); o calculate at least one time-of-flight difference between the mobile and two transmitter bases (4A, 4B), said difference being calculated as the difference between the determined times-of-flight for said bases (4A, 4B); o determine the position of the mobile receiver, from the calculated time-of-flight difference(s) and position data of the transmitter bases (4A, 4B). characterized in that each transmitter base (4, 4A, 4B) is configured to transmit a sum (S1 A, S1 B) of at least two unmodulated pure carrier signals of different frequencies, each pure carrier signal being in the form of an unmodulated continuous wave, which is preferably sinusoidal; and in that the mobile receiver further comprises: • means for measuring, for each given signal frequency and for each respective transmitter base (4A, 4B), the phase of the signal consisting of the various signals (s dA, s rA, s dB, s rB) coming from said base and having said frequency; and • computing means connected to the measuring means and to the storage means, and configured to: o apply, for each transmitter base (4A, 4B), a Fourier transform to a signal consisting of the various measured phases of the radio frequency signals coming from said base (4A, 4B); o determine, for each transmitter base (4A, 4B), from the Fourier transform computed for said base, a time-of-flight between the mobile receiver and said base (4A, 4B); o calculate at least one time-of-flight difference between the mobile and two transmitter bases (4A, 4B), said difference being calculated as the difference between the determined times-of-flight for said bases (4A, 4B); o determine the position of the mobile receiver, from the calculated time-of-flight difference(s) and position data of the transmitter bases (4A, 4B). • means for measuring, for each given signal frequency and for each respective transmitter base (4A, 4B), the phase of the signal consisting of the various signals (s dA, s rA, s dB, s rB) coming from said base and having said frequency; and • computing means connected to the measuring means and to the storage means, and configured to: o apply, for each transmitter base (4A, 4B), a Fourier transform to a signal consisting of the various measured phases of the radio frequency signals coming from said base (4A, 4B); o determine, for each transmitter base (4A, 4B), from the Fourier transform computed for said base, a time-of-flight between the mobile receiver and said base (4A, 4B); o calculate at least one time-of-flight difference between the mobile and two transmitter bases (4A, 4B), said difference being calculated as the difference between the determined times-of-flight for said bases (4A, 4B); o determine the position of the mobile receiver, from the calculated time-of-flight difference(s) and position data of the transmitter bases (4A, 4B). o apply, for each transmitter base (4A, 4B), a Fourier transform to a signal consisting of the various measured phases of the radio frequency signals coming from said base (4A, 4B); o determine, for each transmitter base (4A, 4B), from the Fourier transform computed for said base, a time-of-flight between the mobile receiver and said base (4A, 4B); o calculate at least one time-of-flight difference between the mobile and two transmitter bases (4A, 4B), said difference being calculated as the difference between the determined times-of-flight for said bases (4A, 4B); o determine the position of the mobile receiver, from the calculated time-of-flight difference(s) and position data of the transmitter bases (4A, 4B).