A large number of facts prove that Global Navigation Satellite System (GNSS) has certain security risks and is threatened by attacks. In particular, GNSS civilian signal receivers have some vulnerability in responding to spoofing attack and jamming attack, because the format and modulation of GNSS civilian signals are public. Based on the concerns of existing GNSS spoofing scenarios, this paper reviews the research on GNSS anti-spoofing technologies from two aspects. In this paper, the strategies of spoofing attacks discovered at this stage are classified in detail, the protection effect and scheme implementation complexity of various anti-spoofing techniques against spoofing attacks are analyzed from the perspective of signal-level and data-level. More specifically, we comprehensively analyze the ability for the combined anti-spoofing methods at the signal-level and the data-level to protect from combinations of different spoofing attack. Finally, the future development trend and potential research direction of GNSS anti-spoofing technology are summarized and predicted.

Due to openness and lack of authentication, like other members of the Global Navigation Satellite System (GNSS) Club, BeiDou-II civilian navigation signals are vulnerable to all kinds of spoofing attacks. As a result, both the positioning and timing functions of BeiDou-II civil satellite navigation are likely to be controlled by the spoofer. In this paper, an anti-spoofing scheme of BeiDou-II Navigation Message Authentication & Spread Spectrum Information (BD-II NMA&SSI) is proposed by using SM cryptographic algorithms and spread spectrum information to resist spoofing attacks. The SM cryptographic algorithms are used for generating authentication information to detect spoofing attacks. The spread spectrum information is to protect the authentication information in the D2 navigation messages from modification. Experimental results show that the scheme guarantees the authenticity of BD-II satellite navigation messages, meets the requirement of anti-spoofing and takes a rather less effect on the satellite navigation system.