一个零平衡的总功率辐射仪系统NCS1
1National Institute of Standards and Technology, Boulder, CO 80303-3328.
概括
一个新的辐射计系统NCS1精确校准了从1.0GHz到12.0GHz的热噪声温度. 它以高精度测量冷和热噪声源,为各种连接器提供灵活性.
科学领域:
- 电气工程 电气工程
- 计量学 计量学 计量学
- 无线电天文学 无线电天文学
背景情况:
- 精确校准热噪声温度对于各种科学领域的敏感测量至关重要.
- 现有的辐射计系统在频率范围,准确性或与不同噪声源的兼容性方面可能存在局限性.
研究的目的:
- 介绍和评估新开发的NCS1辐射计系统的性能.
- 为了证明系统在广泛的频率范围内校准热噪声温度的能力.
- 评估系统对不同噪声源和连接器的准确性,灵敏性和多功能性.
主要方法:
- 使用NCS1辐射仪系统进行热噪声温度校准.
- 用冷和热噪声源测试了系统的性能.
- 在1.0GHz至12.0GHz的频率范围内测量噪声温度.
- 评估扩展不确定性和系统灵敏度.
主要成果:
- 该NCS1系统校准的热噪声温度在1.0GHz和12.0GHz之间.
- 它可以测量高达大约10^5K的低温噪声源,而不会损失精度.
- 对于热噪声源 (8400K,反射系数为0.1),扩展不确定性为~1.8%,灵敏度为~2K.
- 该系统采用N型连接器实现,可适应其他同轴连接器和波导.
结论:
- NCS1辐射计系统提供了热噪声温度的准确和灵敏的校准.
- 它的宽频范围和适应性使其成为各种应用的多功能工具.
- 该系统满足了无线电天文学和其他领域精确噪声温度测量的要求.
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