| 摘要 |
PURPOSE:To reduce the size and weight of a power amplifier by adding a lambda/8-wavelength open stub and lambda/8-wavelength short stub to the output terminal of a lambda/4-wavelength distributed constant line. CONSTITUTION:The synthesized impedance Zp of a lambda/8-wavelength open stub 3 and lambda/8-wavelength short stub 4 is expressed by an equation. When the (n) of the equation is an even number, the numerator of the equation becomes zero and the impedance Zp becomes zero. When the (n) is an odd number, on the other hand, the denominator becomes zero and the impedance Zp becomes infinity. In other words, when the lambda/8-wavelength open stub 3 and lambda/8-wavelength short stub 4 are connected with each other, the output terminal of a lambda/4-wavelength distributed constant line 2 is set in a short-circuited state against even-order higher harmonics and in an opened state against odd-order higher harmonics. Therefore, the power loss inside the amplifier element can be reduced to a half and the operating efficiency of the amplification factor can be improved. As a result, this power amplifier can be reduced in size and weight. |
