Journal of the Korea Academia-Industrial cooperation Society (한국산학기술학회논문지)

The Korea Academia-Industrial cooperation Society (한국산학기술학회)
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Design of a IEEE 1588 Based Clock Synchronization System for Femtocell Frequency Signal Generation

펨토셀 주파수 신호 생성을 위한 IEEE 1588 기반 클록 동기화 시스템의 설계

  • Han, Jiho (Department of Electronic Engineering, Sun Moon University) ;
  • Park, Yong-Jai (School of Mechanical and ICT Convergence Engineering, Sun Moon University)
  • 한지호 (선문대학교 전자공학과) ;
  • 박용재 (선문대학교 기계ICT융합공학부)
  • Received : 2015.01.20
  • Accepted : 2015.07.16
  • Published : 2015.07.31
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Abstract

This article presents a circuit and a system for IEEE 1588 based clock synchronization to generate a very accurate frequency signal required in femtocell devices. A prototype board and the experimental environment to verify the functions and to evaluate the performance are explained to verify the feasibility of the proposed synchronization system. To make low-cost femtocells without constraints on the place of installation, it is very important to study on the practical implementation of synchronization system based on IEEE 1588. The experimental result shows that the synchronization errors between -16 ns and 9 ns are guaranteed over the network of femtocell devices with the proposed synchronization circuits, thus the synchronization criteria of the 3GPP HNB are met.

본 논문은 펨토셀에서 요구되는 정확한 주파수 신호 생성을 위한, IEEE 1588 기반의 클록 동기화 회로 및 시스템을 제시한다. 동작 검증 및 성능 평가를 위한 프로토타입 보드와 실험 환경에 대하여 설명하고, 실험 결과가 펨토셀 동기화에 적합함을 확인한다. 펨토셀은 설치 위치의 제약이 없는 저가의 장비로 개발해야 하기 때문에, IEEE 1588 동기화 시스템의 실제 구현에 관한 연구가 매우 중요하다. 제안하는 동기화 회로를 내장한 펨토셀 기지국을 FPGA 보드에 프로그램하고, 그 기지국들의 네트워크에서 실험한 결과 -16 ~ 9 ns 이내의 동기화 오차를 보장함을 관찰하였고, 이는 3GPP의 HNB 동기화 기준을 만족하는 수준임을 확인할 수 있다.

Keywords

References

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