一种高温噪声源设计

针对毫米波、亚毫米波高精度噪声量传需求,文中介绍了一种采用微波辐射体实现的太赫兹频段高温噪声源, 可提供500K左右的等效输出噪声温度,不确定度小于2%。辐射体采用金字塔型高温吸波材料制成,E/H面等化性好。 采用恒温槽加热方式,有效提升了辐射体的温度均匀性。采用一种改进的矩形喇叭天线用作耦合天线,有效降低端口反 射,从而减小了天线对等效输出噪声温度的影响。

Design of a High Temperature Noise Source

In response to the demand for high-precision noise transmission in millimeter and submillimeter waves, a high-temperature noise source applied in THz frequency band using microwave radiator is introduced, which can provide an equivalent output noise temperature of about 500 K with an uncertainty of less than 2%. The radiator is made of pyramid-shaped high-temperature absorbing material, with good homogeneity for both E and H surfaces. The constant temperature bath heating method effectively improves the temperature uniformity of the radiator. An improved rectangular horn antenna is used to reduce the port reflection and thus reduce the effect of the antenna on the equivalent output noise temperature.