Patent ID: 7889751

Claim:
A radio frequency (RF) transmitter comprising: a first parallel-to-serial converter to convert first parallel data corresponding to a I quadrature baseband signal component into a first set of serial data bits; a second parallel-to-serial converter to convert second parallel data corresponding to a Q quadrature baseband signal component into a second set of serial data bits; a plurality of stages, wherein each of the plurality of stages may be activated or deactivated to provide variable gain, and wherein each of the plurality of stages comprises: a first XOR gate coupled to a first transistor, the first XOR gate having a pair of inputs coupled to the first set of serial data bits and a first clock that corresponds to the I quadrature baseband signal component, and having a first output coupled to drive a gate terminal of the first transistor, wherein a source terminal of the first transistor is coupled directly to ground, the first transistor to convert the first set of serial data bits corresponding to the I quadrature baseband signal component from digital-to-analog without using a digital-to-analog converter; and a second XOR gate coupled to a second transistor, the second XOR gate having a pair of inputs coupled to the second set of serial data bits and a second clock that corresponds to the Q quadrature baseband signal component, and having a second output coupled to drive a gate terminal of the second transistor, wherein a source terminal of the second transistor is coupled directly to ground, the second transistor to convert the second set of serial data bits corresponding to the Q quadrature baseband signal component from digital-to-analog without using a digital-to-analog converter; and a mixer to sum the first and second outputs of each of the plurality of stages at a node to obtain a single-side band (SSB) RF output.