Patent ID: 7245170

Claim:
An attenuator, comprising: a first signal line including a first variable resistor connecting a first signal inputting section for high frequency signal to a first signal outputting section; a second signal line including a second variable resistor connecting a second signal inputting section for high frequency signal to a second signal outputting section, said second signal line being arranged in parallel to said first signal line; reference voltage applying sections connected to said first variable resistor and said second variable resistor; and a gain control voltage applying section connected to said first variable resistor and said second variable resistor, wherein: the attenuation characteristics of said first variable resistor and said second variable resistor and the voltage applied to said reference voltage applying sections are set such that the change of the amount of attenuation relative to the chancre in the gain control voltage becomes the same for said first variable resistor and said second variable resistor, said first variable resistor comprises a third variable resistor connecting said first signal inputting section to said first signal outputting section and a fourth variable resistor connecting any one of said first signal inputting section and said first signal outputting section to a reference potential section; said second variable resistor comprises a fifth variable resistor connecting said second signal inputting section to said second signal outputting section and a sixth variable resistor connecting any one of said second signal inputting section and said second signal outputting section to said reference potential section; and said third variable resistor and said fifth variable resistor are connected to said first reference voltage applying section, while said fourth variable resistor and said sixth variable resistor are connected to said second reference voltage applying section, and while each of said third variable resistor, said fourth variable resistor, said fifth variable resistor, and said sixth variable resistor is connected to said gain control voltage applying section.