A method for determining the position, velocity and time, PVT, in particular of people or goods inside buildings or in any sealed area or any area that radioelectric waves emitted by the Global Navigation per Satellite Systems, GNSS, do not easily reach, called white or grey area, this with standard navigation and localization terminals using the radioelectric navigation signals emitted by the GNSS systems, characterized by the fact that: - determining PVT is carried out by means of non-standard synthetic radio signals, the characteristics of which are compatible with the signal processing methods in accordance with the state of the art of the standard GNSS terminals; - said synthetic signals are composed of several compatible components of a set of real GNSS signals; - said synthetic signals are controlled in phase and in magnitude and are radiated according to a method, called transmission method, making it possible to create constant phase planes in separate directions for each of the components of said synthetic signals in the space where the method is implemented; - said transmission method is characterized in that said synthetic signals are radiated by a network of generators, called generators of synthetic signals, producing composite radioelectric signals radiated by multi-beam sources with directivities adapted so as to control the direction of radiation of each of the components of said synthetic signals; - the multi-beam sources are formed by arrays of radiating elements of phased antenna array type in which each of the radiating elements of each of the antennas of said synthetic signal generators composing the array of generators, transmits the weighted sum of the components of said synthetic signals whose the complex weighting coefficients are calculated so as to give a distinct and controlled direction to each of the synthetic signals; - each of the synthetic signals is generated so that the phase of the components of said synthetic signal at the location of the phase center of each of the antennas of said synthetic signal generators emitting this component is identical to the phase of the real signal from which the component of said synthetic signal is compatible if the latter were visible at these same locations; - said synthetic signal generators are arranged in a network in space according to a diagram which ensures total or partial radioelectric coverage of the space where the method is implemented. - determining PVT is carried out by means of non-standard synthetic radio signals, the characteristics of which are compatible with the signal processing methods in accordance with the state of the art of the standard GNSS terminals; - said synthetic signals are composed of several compatible components of a set of real GNSS signals; - said synthetic signals are controlled in phase and in magnitude and are radiated according to a method, called transmission method, making it possible to create constant phase planes in separate directions for each of the components of said synthetic signals in the space where the method is implemented; - said transmission method is characterized in that said synthetic signals are radiated by a network of generators, called generators of synthetic signals, producing composite radioelectric signals radiated by multi-beam sources with directivities adapted so as to control the direction of radiation of each of the components of said synthetic signals; - the multi-beam sources are formed by arrays of radiating elements of phased antenna array type in which each of the radiating elements of each of the antennas of said synthetic signal generators composing the array of generators, transmits the weighted sum of the components of said synthetic signals whose the complex weighting coefficients are calculated so as to give a distinct and controlled direction to each of the synthetic signals; - each of the synthetic signals is generated so that the phase of the components of said synthetic signal at the location of the phase center of each of the antennas of said synthetic signal generators emitting this component is identical to the phase of the real signal from which the component of said synthetic signal is compatible if the latter were visible at these same locations; - said synthetic signal generators are arranged in a network in space according to a diagram which ensures total or partial radioelectric coverage of the space where the method is implemented.