A WIDESCOPE TUNER USING COUPLER AND PIN DIODES

摘要

PURPOSE: A widescope tuner for a mobile communication terminal is provided to measure a VSWR(Voltage Standing Wave Ratio) of a wider range using a directional coupler. CONSTITUTION: Ten pin diodes are used by a switch for changing a stub line length to change a line length which has a fixed interval. 1024 points are extensively distributed in the entire Smith chart area. Lines of no 2 and 3 ports of a directional coupler are compared to obtain one result value. A problem that it is difficult to change a line length is solved when using a single stub.