论文部分内容阅读
把一种先进的UHF电视天线和一个平衡输入的超低噪声预放大器结合起来,就可以在先前不能有效地接收到可见图象的范围内,接收大气层外(over-the-air)的UHF电视节目。 这种天线设计突破了传统的UHF天线的老框框,使整个UHF电视频谱都能得到均匀的增益。 天线预放大器的设计克服了把平衡输入的电视天线阻抗变换为不平衡的预放大器输入阻抗时所引起的固有损耗。其结果是获得了很低的噪声系数。
Combining an advanced UHF TV antenna with a balanced input ultralow noise preamplifier allows for the reception of over-the-air UHF television in areas that have not previously been effective in receiving visible images program. This antenna design breaks through the old frame of a traditional UHF antenna, giving a uniform gain to the entire UHF television spectrum. The design of the antenna pre-amplifier overcomes the inherent loss caused by translating the balanced input TV antenna impedance into an unbalanced pre-amplifier input impedance. The result is a very low noise figure.