DEVELOPMENT OF VERSATILE 8-18 GHZ FT ESR SPECTROMETER

多功能 8-18 GHZ FT ESR 光谱仪的开发

• 批准号: 8363934
• 负责人: Jack H Freed
• 金额: $ 3.3万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-09-01 至 2012-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8363934
• 关键词: Computer software; Data Collection; Development; Frequencies; Funding; Grant; National Center for Research Resources; Output; Performance; Physiologic pulse; Principal Investigator; Process; Research; Research Infrastructure; Resolution; Resources; Signal Transduction; Source; Speed; Staging; System; Technology; Testing; Time; United States National Institutes of Health; Writing; base; cost; data acquisition; design; improved; microwave electromagnetic radiation

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. We made significant progress in finalizing the construction of a new, versatile 8-18 GHz FT-ESR spectrometer. The microwave pulse forming unit, receiver and frequency converters, internal to the microwave bridge, were assembled in their final configuration and to a large extent integrated with the new timing system designed and built at ACERT. Our latest design iteration of timing systems makes it possible to generate pulses in their sequences with 10 picosecond timing resolution and provide all necessary control signals for appropriate spectrometer components. Currently, we are in the process of writing spectrometer control firmware and data acquisition software and finalizing small hardware issues to improve overall system performance at the spectrometer level. The data acquisition is currently based on two AP240 dual-channel 1 Gsps ADC/signal averager PCI cards that capture quadrature signals and average them with very high efficiency. The new spectrometer will use new 4kW Ku-band and/or 8 kW X-band TWTAs with their output power temporarily limited to 2 kW until a new high-power high-speed active receiver protection stage is built to protect the limiting diode from damage. The spectrometer bridge is in the final stage of testing along with the pulse programmer and data collection system.

该子项目是利用资源的众多研究子项目之一 由 NIH/NCRR 资助的中心拨款提供。子项目的主要支持 并且子项目的首席研究员可能是由其他来源提供的， 包括其他 NIH 来源。 子项目可能列出的总成本 代表子项目使用的中心基础设施的估计数量， NCRR 赠款不直接向子项目或子项目工作人员提供资金。 我们在完成新型多功能 8-18 GHz FT-ESR 光谱仪的构建方面取得了重大进展。 微波桥内部的微波脉冲形成单元、接收器和变频器按照最终配置进行组装，并在很大程度上与 ACERT 设计和建造的新计时系统集成。我们最新的计时系统设计迭代可以生成具有 10 皮秒计时分辨率的序列脉冲，并为适当的光谱仪组件提供所有必要的控制信号。目前，我们正在编写光谱仪控制固件和数据采集软件，并解决小硬件问题，以提高光谱仪级别的整体系统性能。数据采集​​目前基于两个 AP240 双通道 1 Gsps ADC/信号平均器 PCI 卡，可捕获正交信号并以非常高的效率对其进行平均。新光谱仪将使用新的4kW Ku波段和/或8kW X波段TWTA，其输出功率暂时限制为2kW，直到建立新的高功率高速有源接收器保护级以保护限流二极管免受损坏。 光谱仪桥以及脉冲编程器和数据收集系统正处于测试的最后阶段。