DESIGN OF PLANAR IMAGE SEPARATING AND BALANCED SIS MIXERS
DESIGN OF PLANAR IMAGE SEPARATING AND BALANCED SIS MIXERS
复制标题
平面图像分离和平衡SIS混合器的设计
DOI：
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发表时间：
1996
期刊：
影响因子：
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通讯作者：
A. Kerr
中科院分区：
文献类型：
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作者：
A. Kerr
由于SIS接收器的噪声温度现在在光子温度（hf/k）的2-4倍的范围内，大气噪声和有时来自本振源的噪声会严重降低射电天文测量的总体灵敏度。在光谱线测量中，使用图像分离方案可以消除不需要的（图像）边带中的大气噪声。为了减少本振噪声，可以使用平衡混频器。利用准光或波导射频电路实现图像分离和平衡混频器是可能的，但它们制造困难且体积庞大。我们认为，现在在同一石英衬底上的SIS混频器中包含必要的信号和LO功率分配器，耦合器和冷负载是可行的。完整的图像分离或平衡混合器可以使用标准的铌SIS混合器制造工艺与一个或两个附加层制造。
With noise temperatures of SIS receivers now in the range 2-4 times the photon temperature (hf/k), the overall sensitivity of radio astronomy measurements can be seriously degraded by atmospheric noise, and sometimes by noise from the local oscillator source. In spectral line measurements, atmospheric noise in the unwanted (image) sideband can be eliminated by using an image separating scheme. To reduce local oscillator noise, balanced mixers can be used. It is possible to realize image separating and balanced mixers using quasioptical or waveguide RF circuits, but they are difficult to fabricate and bulky. We believe it is now practical to include the necessary signal and LO power dividers, couplers, and cold loads with the SIS mixer on the same quartz substrate. The complete image separating or balanced mixer can be fabricated using a standard niobium SIS mixer fabrication process with one or two additional layers.