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The interference factors of radar level gauges mainly include: adherents on the high-frequency head, interference from obstacles on reflections, impedance jumps in short pipes, impedance jumps at antenna connections, and the effect of oil, gas, or steam condensation inside the tank on reflections. Electromagnetic compatibility, which is a common source of interference for instrument signals, has become an important performance indicator for instruments used in industrial process measurement and control. Since measurement and control instruments always operate alongside various devices that generate electromagnetic interference, they are inevitably affected by the electromagnetic environment. Common interference sources are mainly divided into two categories: external interference and internal interference. 3.1 External Interferences 1) Interference from celestial bodies and ionospheric phenomena. Celestial body interference is caused by the electromagnetic waves emitted by the Sun or other stars. Thunderstorm interference is caused by electromagnetic waves and changes in spatial potential generated by natural phenomena such as lightning, atmospheric ionization, volcanic eruptions, and earthquakes. 2) Mechanical interference: Mechanical interference refers to the situation where mechanical vibrations or shocks cause the electrical components in control instruments to vibrate and deform, lead to displacement of connection wires, cause the pointers to shake, and result in loose instrument connections. For mechanical disturbances, vibration reduction measures are primarily employed to address them, such as using vibration-damping springs, vibration-damping pads, and partitions. 3) Thermal interference: The temperature fluctuations and changes in ambient temperature caused by the heat generated by the thermal equipment in thermal power plants during operation can lead to changes in the parameters of the circuit components of control instruments, thereby affecting their proper functioning. 4) Light interference: Various semiconductor components are widely used in control instruments; these components change their electrical conductivity under the influence of light, thereby affecting the proper operation of the control instruments. 5) Humidity interference: Excessively high humidity can cause the insulation resistance of insulators to decrease, as well as increase leakage current ； As the dielectric constant of the dielectric increases, the capacitance increases ； After absorbing moisture, the expansion of the skeleton increases the resistance of the coil, resulting in changes in the inductor ； After the strain gauge is attached, the adhesive softens, resulting in a decrease in accuracy. 6) Chemical interferences: Chemical substances such as acids, bases, and salts, as well as other corrosive gases, not only cause chemical corrosion that can damage instruments, equipment, and components, but they can also generate a chemical electromotive force with metal conductors, thereby affecting the proper operation of control instruments. 3.2 Internal interference: Interference can sometimes originate from within the instrument itself, such as the power transformer, wires, printed circuits, the inductance and capacitance between electronic components, or noise generated within the components themselves.