Abstract Constant‐frequency electromagnetic waves (CFEWs) refer to artificially emitted electromagnetic waves with a constant frequency. Ground stations continuously transmit CFEWs into space at different frequencies. When a satellite passes over a station, it can receive stable CFEWs within a specific frequency range. Based on the frequency shift phenomenon observed in satellite‐monitored CFEWs, this study proposes an automatic method for recognizing frequency shifts and extracting frequency data using computer vision. Applied to data from 8 revisit cycles observed by CSES, this method recognized and calculated the center frequencies of three CFEWs—which exhibited specific frequency shifts of approximately 11.8 kHz, 23.6 kHz, and 17.7 kHz—using a total of 1,602 power spectrograms. The study reveals a consistent pattern of synchronized frequency shifts among the three CFEWs, showing that they tend to shift simultaneously in the same direction—either upward or downward—indicating a coherent response to ionospheric influences. Furthermore, these waves systematically register at higher frequencies in the Eastern Hemisphere. This research establishes an intelligent analytical framework for evaluating signal stability and optimizing anti‐interference capabilities in geophysical and weather research, as well as in seismic monitoring systems.
Han et al. (Fri,) studied this question.