| 摘要 |
PURPOSE:To attain miniaturization of a phase shifter regardless of the wavelength, by connecting the drain outputs of two D-FETs which perform a phase shift with use of an impedance matching device to obtain an output by using the D-FET in place of a 90 deg. hybrid circuit. CONSTITUTION:A D-FET20 earthed to a source is used in place of a 90 deg. hybrid circuit, and a signal is supplied to the 1st gate 32 from an input terminal 30 via a matching circuit 23. The 2nd gate 33 and a drain 34 are connected to the 1st gate of D-FET21 and 22 respectively via matching circuits 24 and 25 respectively. Then a variable bias is supplied to the 2nd gates 28 and 29 of the D-FET21 and 22. Thus a drain output is obtained with about 90 deg. difference of phase and a proper amplitude. The vectors are synthesized through matching circuits 26 and 27 for the above-mentioned drain output. As a result, a joint is defined as an output point 31 to obtain a signal having a phase shift degree corresponding to the variable bias. |
