| 摘要 |
<p>PURPOSE:To reduce the noise index and the insertion loss in the turned-on state, to raise the attenuation characteristic in the turned-off state, and to eliminate the need of forming FETs in many stages to facilitate the design. CONSTITUTION:With respect to a two-input and single-output transmission line, FETs 10 and 25 performing the switch operation and PIN diodes 18 and 33 are provided for respective input lines, and both elements are synchronously turned on/off for each input line. Strip lines 21 and 36 which have high impedances at the time of turning-off operation when viewed from junction points between two inputs and the single output and have prescribed length are provided between these switch elements and junction points. An excellent noise performance is obtained by the existence of FETs 10 and 25, and a higher attenuation characteristic (signal separation performance) is obtained by the existence of PIN diodes 18 and 33.</p> |
