Anti-spoofing is becoming a crucial technique for applications with high navigation accuracy and reliability requirements. Anti-spoofing technique based on Receiver Autonomous Integrity Monitoring (RAIM) is a good choice for most Global Navigation Satellite System (GNSS) receivers because it does not require any change to the hardware of the receiver. However, the conventional RAIM method can only detect and mitigate a single spoofing signal. Some improved RAIM methods can deal with more spoofing signals, but the computational complexity increases dramatically when the number of satellites in view increase or need additional information. This paper proposes a new RAIM method, called the SRV-RAIM method, which has a very low computation complexity regardless of the number of satellites in view and can deal with any number of spoofing signals. The key to the new method is the spatial distribution characteristic of the Satellites’ Residual Vectors (SRV). In replay or generative spoofing scenarios, the pseudorange measurements of spoofing signals are consistent, the residual vectors of real satellites and those of spoofing satellites have good separation characteristics in spatial distribution. Based on this characteristic, the SRV-RAIM method is proposed, and the simulation results show that the method can separate the real signals and the spoofing signals with an average probability of 86.55% in the case of 12 visible satellites, regardless of the number of spoofing signals. Compared to the conventional traversal-RAIM method, the performance is only reduced by 3.59%, but the computational cost is reduced by 98.3%, so most of the GNSS receivers can run the SRV-RAIM algorithm in time.

As an effective deceptive interference technique for military navigation signals, meaconing can be divided into two main types: those that replay directly and those that replay after signal separation. The latter can add different delays to each satellite signal and mislead the victim receiver with respect to any designated position, thus has better controllability and concealment capability. A previous study showed there to be two main spatial processing techniques for separating military signals, whereby either multiple large-caliber antennas or antenna arrays are used to form multiple beams that align with all visible satellites. To ensure sufficient spatial resolution, the main lobe width of the antenna or beam must be sufficiently narrow, which requires the use of a large antenna aperture or a large number of array elements. In this paper, we propose a convenient and effective signal separation method, which is based on an antenna array with fewer elements. While the beam of the array is pointing to a specified satellite, the other satellite signals are regarded as interference and their power is suppressed to a level below the receiver’s sensitivity. With this method, the number of array elements depends only on the number of visible satellites, thus greatly reducing the hardware cost and required processing capacity.