Carrier leak reduction transmitter circuit

The transmitter circuit according to claim 2,

• wherein the mixer comprises a double balanced mixer that includes two first resistors for differential output,
• wherein the transmitter circuit further comprises:
• a second resistor that is connected between a node of the two first resistors and a power supply;
• a limiter amplifier that amplifies a second signal that appears at the node when potentials of a pair of input terminals that input the differential input signals of the double balanced mixer are alternately set to a first potential and a second potential;
• and
• a control unit that changes the first potential and the second potential by using a third signal that is outputted by the limiter amplifier,
• wherein a feedback loop that reduces the amplitude of the second signal by changing the first potential and the second potential, and
• wherein the first potential and the second potential which are converged in the feedback loop is a potential of the DC voltage which corrects the DC offset.

A transmitter circuit, comprising:

• a mixer that conducts frequency conversion of an input signal by using a carrier signal to output a first signal that has been converted in frequency;
• a detector that detects a DC offset of the mixers;
• and
• an adder that adds a DC voltage that corrects the detected DC offset to the input signal of the mixer.