Flex power is a critical technology for enhancing the signal strength of the Global Positioning System (GPS), which significantly improves the anti-jamming capabilities of satellite signals and addresses their inherent vulnerabilities. Accurate and efficient detection of GPS flex power is essential before conducting research in this area. This study presents a novel real-time detection method for GPS flex power. We demonstrate the existence of a linear correlation among the carrier-to-noise ratios ( \(C/N_{0}\) ) of different signals. Utilizing this characteristic, along with the fact that the C/A code power remains constant in the primary flex power mode, we employ the S1C to infer the S2W, thereby enabling real-time detection. This method does not rely on machine learning or grid models regarding the relationship between \(C/N_{0}\) and elevation or azimuth angles. The detection method was validated through both post-event and real-time data. The long-term post-event results showed a True Positive Rate (TPR) of 0.999937 and a False Positive Rate (FPR) of 0.000049. Real-time detection further confirms the method's capability for accurate and efficient real-time detection of flex power. Furthermore, we reveal that GPS flex power induces variations in pseudorange multipath and the Hatch–Melbourne–Wübbena (HMW) for satellite G32, and highlight the need for special attention to this variation in high-precision positioning applications.
