Patent ID: 7848450

Claim:
An apparatus comprising: a modulator having: a positive in-phase terminal that receives a positive portion of an in-phase signal; and a negative in-phase terminal that receives a negative portion of the in-phase signal; a positive quadrature terminal that receives a positive portion of a quadrature signal; and a negative quadrature terminal that receives a negative portion of the quadrature signal; a local oscillator that is coupled to the modulator; and an adjustable resistor network having: a first variable resistor that is coupled between positive in-phase terminal and the positive quadrature terminal; a second variable resistor that is coupled between the negative in-phase terminal and the negative quadrature terminal; a third variable resistor that is coupled between the positive in-phase terminal and the negative quadrature terminal; and a fourth variable resistor that is coupled between the negative in-phase terminal and the positive quadrature terminal.