The Automatic Measuring System Design Of Aerial Radiation Pattern

In the wireless communication system, the Antenna is an important front-end device to radiate and receive the radio waves. It's capability is mainly presented in some electrical parameters, such as antenna pattern, antenna plus, bandwidth and so on. In order to understand and master the characteristics of antenna, the initial method is through theoretical calculation method is obtained. But because there are many approximate theoretical calculation, but there is always some differences between theoretical analysis and practical results., for this reason only by practical measure can tell the truth. The measure of conventional antenna is mainly measure the antenna pattern. Through measuring antenna direction, we can calculate the HPBW, BWFN, SLL and so on.According to the need of the lab research and antenna engineering survey, this paper based on laboratory research, teaching practice and small antenna engineering survey, in antenna as the research object, to pull automatically control technology and virtual instrument engineering platform into the antenna measurements. From two aspects of hardware and software design of the antenna automatic measurement system, and the actual test.The whole hardware whose nucleus is integrated chip-C8051F340 includes stepper motor-driving circuit, return-zero circuit, and controlling mode switching circuit. It transmits and receives wireless signals using transceiver circuit consist of SCM CC1000, and realizes ADC through C8051F340 holding fhe function of A/D.As for software, we use LabVIEW software which holds powerful functions including instrument control, data-processing and graphic demonstration, to design a user interface in the host computer. We use Silicon Laboratorise IDE to develop the control program, which mainly includes controlling stepper motor, returning-zero, A/D, communication of USB and transmitting and receiving wireless. At the same time, we develop assistant-host computer program of transmitting wireless signals via VC language.From the experiment results, this system can realize the automatic control of rotary table, automatic data acquisition, automatic draw of antenna pattern and automatic parameters computation, which greatly decrease the error human factors caused, and improve the measuring accuracy.