Study And Development Of New-type Microwave Experiment System

The microwave measuring line has many characteristics such as structure simple, measure principle clear and price cheap, so it is a main instrument in microwave laboratory in high school. The traditional hand-moving measure, the experimenter reading all main data one by one, not only increases the influence of the few error margins to measuring result but also makes the work have great capacity and the process is tedious and lifeless. Because the electromagnetic wave in the microwave measuring line can not be observed, It is impossible to estimate the shape of electromagnetic wave in the measuring line according to limited data.The application of the Computer Aided Test technology provides vast development foreground for the microwave measuring line technique. JW509 microwave experiment system introduced in this paper is a set of microwave measuring line Computer Aided Test System reformed from TC-26 microwave measuring line. The reformed microwave measuring line system has auto measure function and hand-moving measure function in the meantime. The automatic mode having characteristics of high measuring speed and measuring accuracy can be used as a kind of measuring instrument; Hand-moving mode providing experimenter for a good experiment environment can be used as a kind of experiment equipment.The system working at automatic mode, wo can measure some microwave reflect parameters such as standing wave ratio, reflection factor on line, reflection factor on terminal end, return loss and normalize input impedance; We can also measure scattering parameter of reversible dual-ported network with JW509 microwave experiment system.The tested process is similar to traditional hand-moving operation process when the system works in hand-moving mode. We do not need to read the probe position value and the demodulation voltage value through the measuring scale and the milliammeter. The position data and the electric voltage data can be shown at the display directly, the experimenter can record expediently and directly.Applying software is developed for Windowsxp using VC++6.0 with good user interface realized, real tune display and printing of measure result enabled. With the system, we can also measure kinds of microwave parameters such as crystal block quotiety, reflection coefficient and so on. And the metrical precision of microwave measuring line system is improved.