Secure system for the control of the unlocking of at least one openable panel of a motor vehicle

System for the control of means for locking/unlocking at least one openable panel of a vehicle, in particular an automobile, comprising transmission/reception means (3, 4, 5) and memory means (7) which are carried by the vehicle and transmission/reception means (9, 10, 11) and memory means (13) which are intended to be carried by a user, the transmission/reception means of the vehicle (3, 4, 5) forming a circular shift register in which is stored a pseudo-random code and comprising means (3, 6, 7) for transmitting an interrogation signal which carries such a pseudo-random code, the transmission/reception means of the user (9, 10, 11) comprising means (12, 13, 14) for de-spreading the signal received if the pseudo-random code carried by the said signal is synchronized with a corresponding pseudo-random code stored in their memory means (13) and being intended to transmit a response signal able to control the actuation of the unlocking of the openable panel,

• characterized in that
• the memory means (13) and the transmission/reception means (9, 10, 11) of the user form a circular shift register and furthermore comprise means (9, 12, 13, 14) for transmitting a signal in response which signal carries a pseudo-random code and a signature which is specific to the said transmission/reception means (9, 10, 11) of the user, the transmission/reception means (3, 4, 5) on the vehicle comprising means (6, 7, 8) for de-spreading the signal received if the pseudo-random code carried by the said response signal is synchronized with a corresponding pseudo-random code stored in their memory means (7) and for verifying whether the signal received carries the signature of the transmission means.