PCB 스캐너를 이용한 near field와 far field의 상관관계 연구

Abstract

As the technology is developed, digital electronic equipments are gradually integrated and miniaturized, the changes cannot but being weak for EMI problem. EMI problems can cause the malfunction of equipment, so several countries regulate EMC with forced rules. For the measurement of electromagnetic waves, expensive equipments, requested facilities, etc. must be prepared or expensive test must be requested to the laboratory. Therefore, during the preparation of EMC measures, it's difficult to progress the development of products because of the several limitations, and most electromagnetic interference standards that measurements of radiated emissions (RE) must be performed in the far field, e.g. at an open-area test site or in a semi-anechoic chamber. Since the near field measurements using such as PCB scanner are much cheaper, quicker and more flexible compared to site tests, study a correlation between near field and far field data is great research interest.

Therefore, in this thesis is focused on correlation results from following step. 1. To understand the EMI principle, EMI mechanism is briefly reviewed 2. To obatin an interrelation between PCB scanner and site, a simple microstrip line was designed for measurement, 3. Two types measurement was performed (using PCB scanner and RE test in semi-anechoic chambers). 4. Comparison each measurement result and obtain a correlation

To find the correlation between these measurements, in this thesis, magnitude slope of radiated level was calculated between each frequency, and result of site test is larger than PCB scanner’s about 2.47 times.