NAVIGATION SYSTEM Russian patent published in 2015 - IPC G01S1/24 

FIELD: physics, navigation.

SUBSTANCE: invention relates to radio navigation. The navigation system consists of multiple transmitters and may include a control subsystem. Access protection of a transmitter signal is achieved by: varying the transmitted pseudorandom sequence; varying the temporal arrangement of the pseudorandom sequence in a signal subframe; encrypting the navigation message; absence of data in the navigation signal and the need for authorisation. The navigation system implements autonomous or non-autonomous handover. During of non-autonomous handover, the navigation receiver interacts with the control subsystem through a communication system. The control subsystem transmits the necessary data to the navigation receiver, receives data therefrom and controls operation of transmitters.

EFFECT: protecting a navigation system from unauthorised access, enabling authorisation of navigation receivers therein and implementing handover therefor.

7 cl, 8 dwg