The Reliability Analysis Of Microwave Anechoic Chamber And Its Automatic Test Systems

Recently, with the increasing application of wireless communication, the test techniques of the RF terminal equipments such as the mobile phone are paid more attentions, which mainly include the test of gain, TRP (Total Radiated Power) and TIS (Total Isotropic Sensitivity). These test processes should be in the microwave anechoic chamber. So the characteristics of chamber influence enormously on the test results for equipment under test(EUT).This paper include the establishment of the quiet zone of microwave anechoic chamber, the evaluation of the systems'measurement uncertainty and the research of TIS fast-measuring technique.One of the most important parameters is the reflected level of the quiet zone among the microwave anechoic chamber electric performances. It indicates the chamber stand or fall to a great extent. The smaller the reflected level, the less the measurement error, and the performance of the chamber will be better. In order to ensure the measurement reliability of the systems testing mobile phone radiation performance, the imitation and the field experiments for the quiet zone performance are done by use of geometry optics method and GTD. And the quiet zone area is established under different conditions.Then, the methods evaluating the measurement uncertainty of gain, TRP and TIS automatic test systems in anechoic chamber are studied. The main factors such as the accuracy of equipments, connecting mismatch, environment conditions are discussed respectively. According to the theoretical analysis and long-term measurement experience, the guidance for the improvement of measurement reliability is provided.The traditional test system for TIS is time-consuming using the stepping test technique of Cellular Telecommunications and Internet Association(CTIA). On the basis of the vast manual test data, a new method based on data predication is put forward in this paper. The test result shows the method presented here is validated. The efficiency and stability of the measuring are improved. This new method has great visual engineering application.