| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a vector synthesis type phase shifter having high input saturation characteristics.SOLUTION: A high frequency signal inputted from an input terminal 1 is distributed to four signals, which have equal amplitudes, by a four-phase distribution circuit 2 at phase differences of 0°, 90°, 180°, and 270°. The four-distributed signals are inputted into variable attenuators 3 to 6 where an amplitude is set for each of the signals independently and arbitrarily. The four signals after the amplitude setting are in-phase synthesized at an in-phase synthesis circuit 7 and are outputted from an output terminal 8. When doing so, it is possible to arbitrarily set phases of the outputted signals by appropriately setting attenuation amounts of the variable attenuators 3 to 6. With this construction, phase control is performed using the variable attenuators 3 to 6 constructed by passive circuits whose non-linearities are smaller than those of active circuits, so it is possible to obtain a vector synthesis type phase shifter having high input saturation characteristics.</p> |
