LOW POWER PULSE SPECTROMETER AT 170 & 240 GHZ

170 低功率脉冲光谱仪

• 批准号: 7723908
• 负责人: KEITH A EARLE
• 金额: $ 0.17万
• 依托单位: CORNELL UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2008
• 资助国家: 美国
• 起止时间: 2008-09-01 至 2009-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7723908
• 关键词: Computer Retrieval of Information on Scientific Projects Database; Development; Facility Construction Funding Category; Frequencies; Funding; Grant; Institution; Nature; Operative Surgical Procedures; Other Resources; Phase; Physiologic pulse; Process; Pulse taking; Range; Relaxation; Research; Research Personnel; Resources; Source; Techniques; Temperature; Time; United States National Institutes of Health; Work; desire; millimeter; research study; retinal rods

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. With the recent purchase of powerful continuous wave (cw) sources at millimeter wave frequencies the possibility of performing low power pulse work becomes an intriguing possibility. Recent cw experiments with these sources have demonstrated spectral saturation effects over a range of temperatures from 100K to 250K which may be observed by varying the incident millimeter wave power. Due to the modular nature of the source construction it is straightforward to introduce inexpensive, efficient, rf switches at a convenient point in the frequency multiplier chain (10 - 15GHz) to achieve well-defined pulses at the desired millimeter wave frequency. It would also be possible to introduce rf phase shifters at the same time as the switches to achieve the capability of performing phase cycling operations on these low power pulses. This is possible due to the coherent nature of the multiplication process. Implementation of these ideas will depend on the availability of suitable funding. Even with the current setup, however, we can continue to explore saturation effects, which, when analyzed properly, may be used to infer longitudinal relaxation times which are otherwise difficult to obtain at high frequencies. The further development of the dielectric rod resonator with its B1 enhancing capabilities will also be extremely useful in pursuing these studies. The techniques we have developed on the HF/HF cw spectrometer may also be of use on our 95GHz spectrometer, and we will explore these possibilities as time and other resources permit.

该子项目是利用该技术的众多研究子项目之一 资源由 NIH/NCRR 资助的中心拨款提供。子项目和 研究者 (PI) 可能已从 NIH 的另一个来源获得主要资金， 因此可以在其他 CRISP 条目中表示。列出的机构是 对于中心来说，它不一定是研究者的机构。 随着最近购买毫米波频率的强大连续波 (CW) 源，执行低功率脉冲工作的可能性变得令人着迷。 最近使用这些源进行的连续波实验已经证明了在 100K 至 250K 温度范围内的光谱饱和效应，这可以通过改变入射毫米波功率来观察到。 由于源结构的模块化特性，可以直接在倍频器链（10 - 15GHz）中的方便点引入廉价、高效的射频开关，以在所需的毫米波频率下实现明确的脉冲。 还可以在开关的同时引入射频移相器，以实现对这些低功率脉冲执行相位循环操作的能力。 由于乘法过程的相干性质，这是可能的。 这些想法的实施将取决于是否有合适的资金。 然而，即使使用当前的设置，我们也可以继续探索饱和效应，如果分析得当，饱和效应可用于推断纵向弛豫时间，否则在高频下很难获得纵向弛豫时间。 具有 B1 增强能力的介质棒谐振器的进一步发展也将在这些研究中非常有用。 我们在 HF/HF 连续波谱仪上开发的技术也可能在我们的 95GHz 谱仪上使用，我们将在时间和其他资源允许的情况下探索这些可能性。