Abstract: A phase compensated switched attenuation device 6 is provided for attenuating high frequency signals while maintaining an insertion loss of less than 1 dB up to 3 GHz. A single GaAs FET 12 is coupled between input port 8 and output port 9 in parallel with a 20 dB pad 10 for switching the device 6 between a through state and an attenuation state. First and second isolation FETs 14 and 16 are coupled between the GaAs FET 12 and pad terminals 18 and 19 to isolate the GaAs FET 12, decrease return loss when the GaAs FET 12 is on, and increase isolation of the GaAs FET 12 from the pad 10 when the GaAs FET 12 is on. A resistor 24 or a series combination of a resistor 24 and capacitor 26 can be coupled to the pad terminals 18 and 19 in parallel with the pad 10 to improve return loss when the GaAs FET 12 is on. Resistors 21, 22, and 23 are also provided to reduce distortion, coupling gates of the FETs 12, 14, and 16 to a plurality of voltage references V1 and V2.

Abstract: A phase compensated switched attenuation device 6 is provided for attenuating high frequency signals while maintaining an insertion loss of less than 1 dB up to 3 GHz. A single GaAs FET 12 is coupled between input port 8 and output port 9 in parallel with a 20 dB pad 10 for switching the device 6 between a through state and an attenuation state. First and second isolation FET's 14 and 16 are coupled between the GaAs FET 12 and pad terminals 18 and 19 to isolate the GaAs FET 12, decrease return loss when the GaAs FET 12 is on, and increase isolation of the GaAs FET 12 from the pad 10 when the GaAs FET 12 is on. A resistor 24 or a series combination of a resistor 24 and capacitor 26 can be coupled to the pad terminals 18 and 19 in parallel with the pad 10 to improve return loss when the GaAs FET 12 is on. Resistors 21, 22, and 23 are also provided to reduce distortion, coupling gates of the FET's 12, 14, and 16 to a plurality of voltage references V1 and V2.

Abstract: A balun section formed of a pair of transmission lines connected between separate pairs of corresponding input and output terminals with a pair of capacitors connected in series between the output terminals and another transmission line connected in series with a resistor between the circuit ground and the interconnection between the pair of capacitors. A multisection balun is constructed from a plurality of such balun sections connected in cascade. In one embodiment, the outputs of a pair of multisection baluns are supplied to a circuit such as a mixer or the like.