Microwave Measurement System of Density and Moisture Content Based on Focus Fuzzy Clustering Algorithm

摘要

A new microwave measurement method for density and moisture content of nonmetallic materials is proposed in this paper. According to this method, a measurement system is designed for density and moisture content real-time measurement on high speed product line. In this system, density and moisture content can be measured by a specially designed microwave resonator which has a center hole. When moist material pass through the center hole, density and moisture of the material will cause resonant frequency excursion (RFE) and microwave attenuation (MA) of the resonator. Under the same moisture, density is only related to MA. If RFE and MA are detected, we can calculate moisture content first, then density can be obtained after some correction is made. In order to get high accuracy, a focus fuzzy clustering algorithm is proposed. According to the response characteristic of microwave resonator and the focus fuzzy clustering algorithm, we designed a high accuracy microwave measurement system which can measure density and moisture content simultaneously. Experimental results showed that the measurement system has high accuracy on high speed production line; its accuracy is varied from 94 percent to 98 percent in different months.