A radiant panel radio stimulation device, for emitting a test signal to a reception antenna, said device comprising a subassembly generating excitation electrical signals each having a phase corresponding to a desired phase law {Δ φ n} and at least one emission subassembly configured to amplify and radiate said electrical signals so as to emit a radio beam in a direction determined by said phase law {Δ φ n}, the electrical signals being transmitted by the generating subassembly to the emission subassembly in the form of laser waves modulated by said signals and forming a composite laser beam directed toward the surface of a set of photodetectors incorporated in the emission subassembly, characterised in that, the electrical signal generator subassembly and the emission subassembly being arranged with respect to each other so that the composite laser beam is directed toward the surface of the set of photodetectors with an incidence ( α, β) relative to a reference axis and that it travels a distance D between its point of emission M and a reference point O situated on the reference axis at the surface of the set of photodetectors, the device comprises a correction system (44, 45) configured to measure the values α, β and D and deliver a corrected phase law Δφ n ′ that is substituted for the desired phase law {Δ φ n}, the corrected phase law being defined in such a way that the radio beam produced from the signals generated by the signal generator module is oriented in the direction corresponding to the desired phase law {Δ φ n}, the corrected phase law Δφ n ′ being determined from the calculation of the path-length difference δ n = D n ′ − D generated, at each of the photodetectors, by the angle of incidence of the composite laser beam on the surface of the set of photodetectors of the emission subassembly, Δφ n ′ being defined by the relationship: Δφ n ′ = Δφ n − 2 π f s c ⋅ δ n; D n ′ representing the distance between the point of emission M of the composite laser beam and the position P n of the photodetector considered. characterised in that, the electrical signal generator subassembly and the emission subassembly being arranged with respect to each other so that the composite laser beam is directed toward the surface of the set of photodetectors with an incidence ( α, β) relative to a reference axis and that it travels a distance D between its point of emission M and a reference point O situated on the reference axis at the surface of the set of photodetectors, the device comprises a correction system (44, 45) configured to measure the values α, β and D and deliver a corrected phase law Δφ n ′ that is substituted for the desired phase law {Δ φ n}, the corrected phase law being defined in such a way that the radio beam produced from the signals generated by the signal generator module is oriented in the direction corresponding to the desired phase law {Δ φ n}, the corrected phase law Δφ n ′ being determined from the calculation of the path-length difference δ n = D n ′ − D generated, at each of the photodetectors, by the angle of incidence of the composite laser beam on the surface of the set of photodetectors of the emission subassembly, Δφ n ′ being defined by the relationship: Δφ n ′ = Δφ n − 2 π f s c ⋅ δ n; D n ′ representing the distance between the point of emission M of the composite laser beam and the position P n of the photodetector considered.