为减小外场环境温度的影响,提高电磁兼容性(EMC)测试设备的测量精度,提出了一种电磁兼容测量天线系数温度误差修正方法.首先,根据1m距离两天线校准原理,理论推导了近场情况下采用透波材料制作的温控装置对接收天线接收特性的影响,结合仿真分析与试验结果,验证了使用温控装置带来的测试误差可控制在允许的范围内.然后,在此基础上,通过实际测试获得了典型天线的天线系数随温度的变化规律及误差修正曲面.最后,采用对比标准条件下和开阔试验场条件下的测试结果的方法来验证该方法的有效性.结果表明,在保证测量精度的前提下,通过天线系数温度误差修正,可将天线的使用环境温度扩展到-40~+50℃,进而减小外场试验测试误差.适用于双锥、对数周期和双脊喇叭等天线的天线系数温度误差修正.
In order to reduce the influence of the outfield environmental temperature and improve the measuring precision of electromagnetic compatibility(EMC) test equipment, a method for antenna factor tem- perature error correction was presented. Firstly, according to the principle of two antenna calibration with 1 m distance, the antenna receiving characteristic influenced by temperature control device made by radome mate- rial under the condition of near field was theoretically deduced. Combined with the simulation analysis and test results proved that the test error can be controlled in the permitted range by using the temperature control device. Secondly, on this basis the antenna factor variation with temperature and temperature error correction surface for typical antenna was obtainedby the actual test. In the end, the method was verified by comparing the test result uder standard conditions with the test result under the open area test site (OATS) condition. The results prove that this method can expand the environmental temperature range of use from -40~C to 50~C by antenna factor temperature error correction on the premise of not reducing measurement precision, and suit- able for the antenna factor temperature error correction in EMC double cone antenna and log periodic antenna and the double ridged horn antenna, etc.