基于Aurora协议光纤实时信号传输性能测试  

Real-time signal transmission performance tests with optical fiber based on Aurora protocol

作　　者：鲁睿其 曾健平[1] 赵豫斌 任海龙[1,2] 

机构地区：[1]湖南大学物理与微电子科学学院,长沙410082 [2]东莞中子科学中心,东莞523808

出　　处：《核技术》2015年第3期47-51,共5页Nuclear Techniques

基　　金：中国散裂中子源工程(发改高技(2008)2578号);湖南省科技计划项目(No.2014Gk3148)资助

摘　　要：作为中国散裂中子源(Chinese Spallation Neutron Source,CSNS)谱仪之一的通用粉末衍射仪(General Purpose Powder Diffractometer,GPPD)采用二维位置灵敏探测器(Symptom Scale of Neurotransmitter Deficiency,SSND)探测中子入射位置和时间信息,并由后端电子学进行信号处理。中子信息以打靶时刻T0为时间参考点,电子学系统控制电路需要将接收到的T0信号低延迟、低抖动实时地传给下级电路。本文介绍了一种基于Spartan6系列FPGA的控制电路,采用Aurora协议通过光纤实时传输T0信号方案,并验证了此方案的可行性。Background： General Purpose Powder Diffractometer （GPPD） is one of Chinese Spallation Neutron Source （CSNS） diffractometers, which adopts Symptom Scale of Neurotransmitter Deficiency （SSND） detecting the position and the flight time of neutron when it hits, and the electronics system processes the detected neutron information. The shooting time TO, as a time reference point of the electronics system, is a real time signal. Traditional cable transmission meets the real-time signal transmission requirements, however, laying work will be rather complex and bring great difficulties to project since numerous of cable was needed. Purpose： The electronics control circuits is needed to transfer the received signal TO to the lower electronics in real time with low propagation delay and low jitter via optical fiber, and the the propagation delay is less than 1 μs which including the 15-m optical fiber delay, the jitter is less than 0.1 ~ts. Methods： This paper describes a transferring scheme based on Spartan6 XC6SLX75T FPGA using Aurora protocol via optical fiber. The testing program is based on ISE Design Suite14.4 FPGA development platform, adopting high-precision oscilloscopes to the measure and calculate the transmission delay and jitter of different rise time signal TO repeatly. Results： Repeated measurements show that the maximum propagation delay is less than 600 ns and that the maximum jitter is less than 4 ns, in addition, the stability of jitter stability is good, and it meets the system requirements. Conclusion： It is feasible to use Aurora protocol via optical fiber to transfer real-time signal TO. Signal rise time has a certain influence on the delay and jitter, longer signal rise time corresponds longer delay and greater the jitter, so to shorten rise time of signal can reduce the transmission delay and jitter.

关 键 词：中国散裂中子源 通用粉末衍射仪 实时信号 抖动 Aurora协议 光纤 

分 类 号：TN41[电子电信—微电子学与固体电子学] TN492