低AM噪声的传输波的生成为次GHz CW-EPR光谱仪
Hideo Sato-Akaba1, Tsukasa Sakai1, Hiroshi Hirata2
1Department of Systems Innovation, Graduate School of Engineering Science, Osaka University, 1-3 Machikaneyama-cho, Toyonaka, Osaka 560-8531, Japan.
Journal of magnetic resonance (San Diego, Calif. : 1997)
|February 23, 2024
概括
一个新的射频 (RF) 发射器放大器有效清除振幅调制 (AM) 噪声,显著改善了亚千兆赫兹连续波电子磁共振 (CW-EPR) 频谱的观测.
科学领域:
- 物理 物理学 物理
- 频谱学是一种光谱学.
- 电子 电子 电子 电子 电子 电子 电子
背景情况:
- 无线电频率 (RF) 传输波中的振幅调制 (AM) 噪声是观测亚千兆赫兹连续波电子偏磁共振 (CW-EPR) 频谱的主要限制.
- 现有的CW-EPR光谱仪通常依赖于频率调制 (FM) 来自动控制频率,因此容易受到AM噪声干扰.
研究的目的:
- 开发和描述一种能够清除AM噪声的射频发射器放大器.
- 通过减轻射频传输中的AM噪声来增强亚千兆赫兹CW-EPR光谱学的灵敏度.
主要方法:
- 开发一个多级射频发射器放大器,利用输出和来抑制AM噪声.
- 在750MHz载波频率和29dBm输出功率下,放大器的AM和相调制 (PM) 噪声性能的表征.
- 在10kHz和100kHz的偏移频率下对AM噪声抑制水平的评估.
主要成果:
- 开发的三级放大器有效地抑制了AM噪声,在10kHz时降至-176dBc/Hz,在100kHz的偏移频率时降至-183dBc/Hz.
- 添加粒子噪声在100kHz偏移时测量了-171dBc/Hz,表明频率调制 (FM) 的扭曲最小.
- 该技术证明了显著的AM噪声降低,这是使用反射桥的CW-EPR光谱学的关键因素.
结论:
- 开发的射频放大器有效清除AM噪声,这对于敏感的次千兆赫兹CW-EPR测量至关重要.
- 这种技术提供了一种可行的方法,通过减少主导的AM噪声来提高传统CW-EPR光谱仪的灵敏度.
- 放大器能够抑制AM噪声而不会扭曲FM,这使得它适合用于需要自动频率控制的光谱仪.
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