| 摘要 |
PURPOSE: To at a high speed and continuously measure water content of a material by a method in which a microwave signal is fed into the material and the speed change of the signal passed is measured, based on the known interdependent relationship between the speed change of the signal and the water content of the material. CONSTITUTION: A directionality coupler 6 divides a microwaver signal into a first component I and a second component II, and the component I is fed to a transmitter 7 and the signal is fed into a material to be measured. A receiver 8 receives a microwave signal I passed through the material to be measured. The transmitter 7 and receiver 8 are disposed counter to each other across the material. On the way of passing the material, the signal I is decelerated more than the signal component II used as the reference amount in a mixer 9, and delayed in a time manner. The mixer 9 mixes the signals I, II to generate an intermediate frequency signal Δf, which is fetched out from an output gate IF to measure frequency of the signal Δf in a counter 3. Water content of the material to be measured can be acquired from this frequency based on the known interdependent relationship between the signal Δf and the water content. |
