Microwave Water Level Detector

Water and humanity have always been closely related,and the study of water level is very beneficial to the effective control of water.The control and detection of water levels has always been a very important scientific research.From the aspects of water conservancy projects,industrial water levels,reservoir water levels,agricultural water irrigation,and various types of storage tanks,the study of water level detection is crucial.In this thesis,microwave detection method was used to study the water level detection,and a low-cost and miniaturized microwave water level detector was realized.This thesis mainly combines the reflection method of microwave non-destructive testing with phase detection to apply to water level detection.The principle of the method in this thesis is to place the microwave sensor coplanar waveguide in the water.The change of the water level makes the phase of the microwave reflected signal different from the original incident signal,and then detects the phase of the reflected signal.Due to the difference between the reflection phase and the initial phase,the phase difference detection module is used to convert the phase signal into a voltage signal.The system uses the voltage value collected by the single-chip microcomputer for data processing,and finally displays the corresponding water level value.The method realizes that the change of the water level produces a corresponding phase change,and the water level is measured indirectly from the detection phase.The system developed by this thesis includes microwave signal source,microwave emission channel,reflection receiving channel,microwave sensor,phase detection processing part and data processing display unit.When the system detects the water level,the microwave signal source used is a single-frequency signal with a frequency of 1 GHz.This article first studied and analyzed the current situation of water level detection,and then determined the overall scheme and parameters of the system detection based on the microwave detection theory.Based on the scheme of the system,the feasibility analysis of the scheme was carried out.Then a number of microwave devices and circuit elements of the system were designed,including conductor-backed coplanar waveguide,power divider,directional coupler,low-pass filter,amplitude phase detection module,and data processing display module.Microwave water level detector based on microwave detection technology.Its microwave sensor of conductor-backed coplanar waveguide type and overall structure are relatively novel.The system structure is easy to miniaturize,the detection is simple and easy to operate,the application range is wide,and the cost is low.It enables real-time detection and recording.