MIXER
A mixer includes a transistor to which an IF signal of ae positive phase side is input, a transistor to which an IF signal of a negative phase side is input, a transistor to which an LO signal is input, and a synthesizer which synthesizes components of a RF frequency band output from the drain terminals of the transistors in a negative phase, and synthesizes components of an IF frequency band output from the drain terminals of the transistors in the same phase.
1 - 5 . (canceled)
6 . A mixer comprising:
a first transistor including a gate terminal to which an IF signal of a positive phase side is input;
a second transistor including a gate terminal in which an IF signal of a negative phase side is input;
a third transistor including a gate terminal to which an LO signal is input, a source terminal which is connected to ground, and a drain terminal which is connected to a source terminal of the first transistor and a source terminal of the second transistor; and
a synthesizer configured to:
synthesize a component of an RF frequency band output from a drain terminal of the first transistor and a component of the RF frequency band output from a drain terminal of the second transistor in a negative phase; and
synthesize a component of an IF frequency band output from the drain terminal of the first transistor and a component of the IF frequency band output from the drain terminal of the second transistor in a common phase.
7 . The mixer according to claim 6 , wherein the synthesizer is a rat race type coupler, and includes:
a first terminal connected to the drain terminal of the first transistor;
a second terminal connected to the drain terminal of the second transistor,
a third terminal configured to output an RF signal;
a first transmission line having a length λLO/2 and connecting the first terminal to the second terminal, wherein λLO is a wavelength of the LO signal;
a second transmission line having a length λLO/4 and connecting the first terminal to the third terminal; and
a third transmission line having a length 3λLO/4 and connecting the second terminal to the third terminal.
8 . The mixer according to claim 7 , wherein when a wavelength of a signal of a highest frequency in the IF signal is defined as NIF, a wavelength of the LO signal is defined as λLO, a relationship of λLO=α×λIF is satisfied, wherein 0≤α≤0.12.
9 . The mixer according to claim 8 , wherein the first transmission line has a folded portion between the first terminal and the second terminal.
10 . The mixer according to claim 7 , wherein the first transmission line has a folded portion between the first terminal and the second terminal.
11 . The mixer according to claim 6 , further comprising:
a first capacitor between the drain terminal of the first transistor and a first terminal of the synthesizer; and
a second capacitor between the drain terminal of the second transistor and a second terminal of the synthesizer.
12 . A mixer comprising:
a first transistor including a gate terminal connected to an IF signal of a positive phase side is input;
a second transistor including a gate terminal in which an IF signal of a negative phase side is input;
a third transistor including a gate terminal to which an LO signal is input, a source terminal which is connected to ground, and a drain terminal which is connected to a source terminal of the first transistor and a source terminal of the second transistor; and
a synthesizer configured to:
synthesize a component of an RF frequency band output from a drain terminal of the first transistor and a component of the RF frequency band output from a drain terminal of the second transistor in a negative phase; and
synthesize a component of an IF frequency band output from the drain terminal of the first transistor and a component of the IF frequency band output from the drain terminal of the second transistor in a common phase, wherein the synthesizer is a rat race type coupler, and includes:
a first terminal connected to the drain terminal of the first transistor;
a second terminal connected to the drain terminal of the second transistor; and
a third terminal configured to output an RF signal.
13 . The mixer according to claim 12 , wherein the synthesizer further comprises:
a first transmission line having a length λLO/2 and connecting the first terminal to the second terminal, wherein λLO is a wavelength of the LO signal.
14 . The mixer according to claim 13 , wherein the first transmission line has a folded portion between the first terminal and the second terminal.
15 . The mixer according to claim 12 , wherein the synthesizer further comprises:
a second transmission line having a length λLO/4 and connecting the first terminal to the third terminal, wherein λLO is a wavelength of the LO signal.
16 . The mixer according to claim 12 , wherein the synthesizer further comprises:
a third transmission line having a length 3λLO/4 and connecting the second terminal to the third terminal, wherein λLO is a wavelength of the LO signal.
17 . The mixer according to claim 12 , wherein when a wavelength of a signal of a highest frequency in the IF signal is defined as λIF, a wavelength of the LO signal is defined as λLO, a relationship of λLO=α×λIF is satisfied, wherein 0≤α≤0.12.
18 . The mixer according to claim 12 , further comprising:
a first capacitor between the drain terminal of the first transistor and the first terminal of the synthesizer; and
a second capacitor between the drain terminal of the second transistor and the second terminal of the synthesizer.