en 5-Signal Processing Signal Processing Research Paper Research Paper <span style="font-size:10.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">The Receiver Autonomous Integrity Monitoring (RAIM) method uses additional information to detect and remove spoofing signals by analyzing pseudo-range measurements. Therefore, assuming that spoofing signals are errors for the valid signal, RAIM can be a practical method that does not impose expensive hardware to the receiver. Typically, RAIM operates under the assumption that simultaneous multi-satellite errors are highly unlikely. For example, GPS satellite errors occur no more than three times per year. Some enhanced RAIM methods have been proposed in recent years that employ additional measurements, such as Doppler shift measurements, time-differential carrier phase measurements, and so on. Since simultaneous multiple fake satellites are common in spoofing cases, basic RAIM cannot counter these types of signals, and for eliminating more than one spoofing or error signal requires additional information, such as measurements on other frequencies or satellite systems, which increases the complexity of execution. In this paper, an anti-spoofing method based on Advanced RAIM (ARAIM) has been proposed with a novel </span></span><span style="font-size:10.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">slope-based RAIM availability assessment method</span></span><span style="font-size:10.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">. Simulation results on several spoofing data sets indicate the definitive success of the proposed methods in detecting and mitigating spoofing error, with a detection success rate of over 79% using the statistical method and over 87% using the Kalman filter method.</span></span> Anti-spoofing, GPS, Kalman Filter, RAIM. 4069 4069 http://ijeee.iust.ac.ir/browse.php?a_code=A-10-78-38&slc_lang=en&sid=1 Maryam Moazedi moazedi@uma.ac.ir 1800319475328460017631 1800319475328460017631 Yes Department of Engineering Sciences, Advanced Technologies, University of Mohaghegh Ardabili, Namin, Iran. Mohammad Reza Mosavi m_mosavi@iust.ac.ir 1800319475328460017632 1800319475328460017632 No Department of Electrical Engineering, Iran University of Science and Technology Narmak, Tehran 16846-13114, Iran. Diego Martín De Andrés diego.martin.andres@uva.es 1800319475328460017633 1800319475328460017633 No Department of Computer Science, Universidad de Valladolid