论文标题
密切间隔的两元素干涉仪的设计方程包括内部噪声耦合
Design Equations for a Closely-Spaced Two-Element Interferometer Including Internal Noise Coupling
论文作者
论文摘要
我们提出了一个两元素的紧密间隔干涉仪的设计方程，以测量均匀天空的噪声温度。这样的干涉仪可用于观察高度分散的无线电源，例如银河系和宇宙信号。我们基于放射物理学和天线理论开发了一个简单的等效电路，以描述关键设计参数之间的相互作用，例如天线自我和相互阻抗和接收器的噪声参数。后者被认为是内部噪声。这种方法直接促进了设计研究，因为可以使用相同的等效电路分析均匀信号的响应和由于内部噪声耦合而导致的系统误差。等效电路表明，由于内部噪声耦合而引起的相互连贯性不可忽略，并且是一个紧密间隔干涉仪的固有特性。一个现实的示例设计，涉及从50到100 MHz的宇宙学信号检测的有损地面上的两个紧密间隔的水平偶极子作为例证。
We present design equations for a two-element closely-spaced interferometer for measuring the noise temperature of a uniform sky. Such an interferometer is useful for observing highly diffuse radio sources such as the Milky Way and Cosmological signals. We develop a simple equivalent circuit based on radiophysics and antenna theory to describe the interactions between key design parameters such as antenna self and mutual impedance and noise parameters of the receiver; the latter is considered internal noise. This approach straightforwardly facilitates design studies as the response of the uniform signal and the systematic error due to internal noise coupling can be analyzed using the same equivalent circuit. The equivalent circuit shows that mutual coherence due to internal noise coupling is non-negligible and an inherent property of a closely-spaced interferometer. A realistic example design involving two closely-spaced horizontal dipoles over a lossy ground for Cosmological signal detection from 50 to 100 MHz is discussed as an illustration.
