Design Of RF Level Instrument Based On Wireless Communication

The level measurement is very important in the industry. With its construction simply, working dependability, supporting convenience, the level instrument with capacitance is very important in level field. However, the level instrument with capacitance will produce error resulted in hang material when it is used in conductive and sticky material,so the applying of level instrument with capacitance is limited. In addition, the general level instrument communicate with RS232 or RS485, which exist interference resulted in thecommon earth in communication, and on the complicated industrial environment, there are some problems in communication: measurement error, chemeical transformation, hard installation and so on. Accordingly, a new kind of level instrument based on RF principles and wireless communication is designed for solving these problems in this paper.RF admittance level measuring principle is discussed in detail and the method of eliminating the hang material's effect and getting the true level is given in this paper, the next, the design of hardware circuit for the RF principle such as power circuit, reset circuit, the circuit of signal generator, signal detection circuit, the filter circuit, the circuit of signal collection, the interface of wireless communication. Finally the software is given, particularly the design of agreement in wireless communication in this paper.The embedded design is given in this paper, and the instrument not only improves traditional capacitive level instrument in deceitful level resulted in hang material, but also obviously reduces error and influence in bad industry environment. The instrument has the characteristic of realtime, high accuracy, and can be widely used.