Mixing apparatus

A direct conversion receiver for down-converting an RF input signal to a base band signal including a mixer circuit, said mixer circuit comprising:

• a pair of switching transistors, each of which having first, second and third terminals,
• a single ended input connected to the first terminals of the pair of switching transistors,
• a local oscillator input connected to the second terminals of the pair of switching transistors for controlling the switching of the transistors,
• a serial capacitor connected in serial connection between the single ended input and the first terminals of the pair of switching transistors, and
• a pair of output capacitors, each of which being connected to a third terminal of the pair of switching transistors, said third terminals of said pair of switching transistors forming an output port for outputting the converted signal.

A means for mixing first and second input signals and for producing a mixed output signal, comprising:

• a switching pair,
• a single ended input connected to said switching pair,
• a local oscillator input for controlling the switching pair,
• a serial capacitor connected in serial connection between the single ended input and the switching pair, and
• a pair of output capacitors, each of which being connected to an output of one of the switches of said switching pair.