This degree paper deals with the mechanism for authentication of navigation messages in the open service (OS) of the Galileo satellite-based system, called OS-NMA. This allows the GNSS receiver to verify the authenticity of the GNSS information and the entity that transmits it, in order to confirm that it comes from a trusted source. Until today or until the creation of this degree paper, it was not possible to confirm that the received navigation and time data really came from their apparent origin. Galileo is currently experimentally becoming the first constellation to include the NMA mechanism in the OS signal.
Galileo is a European global navigation satellite system under civilian control, which can be used in many economic areas, especially those related to transport and intelligent transport systems. Both natural disturbances and those caused by known or unknown radio systems or individual devices can cause a deterioration in accuracy or even a loss of position. As this poses a serious threat to an increasing number of GNSS-dependent services, thinking in the direction of reducing these risks has led to the OS-NMA proposal.
Galileo OS-NMA is based on a hybrid approach of symmetric/asymmetric key techniques known as the TESLA protocol. As this protocol, due to its properties, including strong resistance to data loss, is very suitable for authentication in the field of radio navigation, it makes sense to test how OS-NMA works in difficult conditions of GNSS signal reception, as is the case with GNSS receivers in environments with reduced visibility or detection of satellites.
That authentication in some location-supported systems in transport is unnecessary or doesn't make sense proved to be in the case of the pan-European eCall system, which in the event of an accident sends a message with the location to the emergency response center and speeds up assistance to drivers. Namely, from the legal point of view, the rescue services are obliged to deal with all, either genuine or test or fake eCall emergency calls.
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