In-building Coverage용 RoF 시스템에 적합한 4X8 스위치 모듈
- 발행기관 고려대학교 대학원
- 발행년도 2004
- 학위명 박사
- 학과 대학원:전파공학과
- 식별자(기타) DL:000014914198
- 서지제어번호 000045212759
초록/요약
RoF(Radio over Fiber) technique is one of the most adequate in constructing systems with In-building coverage (0.7 ~ 2.5 GHz). The key point of RoF technique expand the service coverage of wireless communication by using broadband DAS(Distributed Antenna Systems) , and the switching system for supporting DAS is also very important because switching system determine whether transmit the service signals into DAS or not. It is necessary to make the switching system as the combination of switching module for the flexibility and cost reduction of systems. Therefore, the switching module is required to have small size and low production cost. In this thesis, we propose the 4X8 switching module well-suited to the RoF (Radio over Fiber) systems for In-building coverage (0.7 ~ 2.5 GHz). The 4X8 switching module plays a role in combining and transmitting the relevant service channels among 4 input signals according to the demand of users in 8 broadband DAS(Distributed Antenna Systems) terminals. The 4X8 switching module consist of main 3 parts, that are 8-way power divider, 4-way power combiner and ON/OFF switches. We could make the most appropriate 4X8 switching module by comparing 3 prototype models of 4X8 switching module and by selecting appropriate ones among the commercial RF switches. Final model is of small size of 146X100X60 mm3 by using the novel transition structure that can combine between 2 microstrip lines with 90 arrangement. It has the return loss better than -15 dB and the insertion loss of -15.9 ~ -18.5 dB over In-building coverage regardless of the ON/OFF operations in the other ON/OFF switch blocks.
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