Summary: | 碩士 === 國立中正大學 === 電機工程研究所 === 107 === This paper can be divided into two parts. The first topic is to measure the pattern of multi-port antenna by using multi-port antenna planar near-field measurement system and verify the accuracy of the platform. The multi-port antenna planar near-field measurement system is composed of a 24-port network analyzer, a platform that can control movement in the XY axis, and a planar near-field to far-field algorithm of multi-port antenna. At the beginning of the paper, I will introduce the multi-port antenna planar near-field measurement system, the near-field to far-field algorithm, and how to measure the absolute gain of the antenna. It will also be discussed whether the calculation error of the algorithm may cause errors in the measurement result and the limit of the Probe antenna due to the difference in antenna position. In the section next follows, it will be indicate parameters whether the characteristics of the multi-port antenna are good or bad, the reflection coefficient of the antenna, the antenna pattern E cut and H cut , the antenna gain, the antenna efficiency, and the envelope correlation coefficient..The second topic is to measure the human body shadowing effect at a millimeter wave of 38 GHz. At the beginning of this topic, I will introduce what is the meaning of channel and how to measure the channel. The algorithm used to capture the data of the instrument, controls the movement of the planar and performs cross-correlation calculation to obtain channel-related parameters such as delay time, path loss and multi-path reflection. With these parameters, you can also measure the effects of human shadowing effects in specific environments. The measurement environment is divided into the following three types: street canyons, open squares, and indoor offices. The purpose of this measurement is to know whether the presence and movement of the person will affect the user under the specific environment and at certain height position. The results also show that the shadowing effect of the human has little effect on the main beam at the user end when the transmitting antenna is at a high position. At the end of the paper, the measurement results of human body shadowing effect are compared with the double knife edge model proposed by 3GPP. The result shows that the shadow model can accurately calculate the minimum loss under human body shadow, but the actual measured loss at some points will be larger than the shadow model calculation.
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