A Microwave Counter Produced by Photoconductive Sampling

• Main Authors: Huo-Feng Chiu, 邱和風
• Other Authors: Chen-Shiung Chang
• Format: Others
• Language: zh-TW
• Published: 1995
• Online Access: http://ndltd.ncl.edu.tw/handle/09953375566809563089

碩士 === 國立交通大學 === 光電(科學)研究所 === 83 === At present,frequency counter is the most accurate instrument for measuring signal frequency.Since such counter consists of a digital logic circuit,the upper limit of countable frequency will be limited by the response speed of this circuit.Although some strategies of transformation do increase this upper limit a little ,the situation is not much improved.In our experiment, we adopt the fast speed electronic devices(photoconductive) switch instead of the usual devices.such novel counter,we study the countable frequency range,sensitivity and stability of the system and the accuracy of measurement. So far our counter can count signal frequency more then 3.5 GHz with sensitivity 1dBm and the input signal frequency modulation tolerance can attain 40MHz,the accuracy of frequency attains the order of Hz .