Frequency mixing

An apparatus comprising:

• a mixer circuit comprising:
• multiple local oscillator nodes;
• a first node corresponding to a first frequency;
• multiple second nodes corresponding to a second frequency;
• multiple capacitors coupled between the multiple local oscillator nodes and the multiple second nodes;
• multiple switches comprising a first switch, a second switch, a third switch, and a fourth switch;
• the multiple switches coupled between the multiple capacitors and the multiple second nodes;
• the first switch and the second switch coupled between the multiple capacitors and the first node;
• the third switch and the fourth switch coupled to each other via a floating node;
• and
• means for increasing symmetry-dependent linearity.

An apparatus comprising:

• a mixer circuit comprising:
• a first local oscillator node and a second local oscillator node;
• a first node corresponding to a first frequency;
• a second node and a third node each corresponding to a second frequency;
• a first capacitor and a second capacitor;
• a first switch coupled between the first capacitor and the second node, the first switch further coupled between the first capacitor and the first node;
• a second switch coupled between the second capacitor and the third node, the second switch further coupled between the second capacitor and the first node;
• a third switch coupled between the first capacitor and the third node;
• and
• a fourth switch coupled between the second capacitor and the second node,
• the first capacitor coupled between the first local oscillator node and the first and third switches, and the second capacitor coupled between the second local oscillator node and the fourth and second switches.

A method for mixing signals, the method comprising:

• receiving, via a first node, a first signal at a first switch and a second switch, the first signal corresponding to a first frequency;
• receiving, via a first capacitor, a plus local oscillator signal at the first switch and a third switch;
• receiving, via a second capacitor, a minus local oscillator signal at the second switch and a fourth switch;
• mixing the first signal, the plus local oscillator signal, and the minus local oscillator signal to produce a second signal using the first, second, third, and fourth switches, the second signal corresponding to a second frequency;
• and
• providing, via multiple second nodes, the second signal from the first, second, third, and fourth switches.