Patent ID: 7167686
Filing Date: 2007-01-23
Classification: H03C,H03D,H03L,H04B

Abstract:
1. A wireless communications transmitter circuit comprising: a local oscillator for producing a signal at a multiple of an intermediate frequency; a quadrature modulator harmonic rejection mixer responsive to the signal at the multiple of the intermediate frequency for modulating an in-phase base-band signal and a quadrature-phase base-band signal to produce an intermediate frequency signal, wherein the quadrature modulator harmonic rejection mixer includes: a filter responsive to the intermediate frequency signal for producing a filtered intermediate frequency signal; and an RF output offset phase-locked loop responsive to the filtered intermediate frequency signal and responsive to the signal at the multiple of the intermediate frequency for producing an RF transmission signal; wherein the local oscillator produces a frequency equal to a frequency of the RF transmission signal multiplied by said multiple and divided by a sum of one plus the multiple.