Apparatus and method for low voltage radio transmission

An apparatus comprising:nan upconverter comprising at least one transistor;an analog predistorter configured to receive an input signal and to generate a predistorted signal that at least partially corrects non-linearity of the at least one transistor of the upconverter; anda filter disposed in a signal path between the predistorter and the upconverter, wherein the filter is configured to filter the predistorted signal to generate a filtered predistorted signal, wherein the filtered predistorted signal is provided as an input to the upconverter, wherein the filter is configured to reduce out-of-band noise generated by the predistorter,wherein the analog predistorter comprises:na resistor having first and second terminals, wherein the first terminal is electrically connected to a first node and the second terminal is coupled to a second node;a first bias current generator having an output electrically connected to the first node;a first operational amplifier having an inverting input connected to a first baseband input terminal, a non-inverting input electrically connected to the first node, and an output associated with a first input of the upconverter;a first transistor having a gate connected to the output of the first operational amplifier, a source connected to a voltage reference, and a drain connected to the first node;a second bias current generator having an output electrically connected to the second node;a second operational amplifier having an inverting input connected to a second baseband input terminal, a non-inverting input connected to the second node, and an output associated with a second input of the upconverter; anda second transistor having a gate connected to the output of the second operational amplifier, a source connected to the voltage reference, and a drain connected to the second node.

An apparatus comprising:nan upconverter comprising at least one transistor;an analog predistorter configured to receive an input signal and to generate a predistorted signal that at least partially corrects non-linearity of the at least one transistor of the upconverter; anda filter disposed in a signal path between the predistorter and the upconverter, wherein the filter is configured to filter the predistorted signal to generate a filtered predistorted signal, wherein the filtered predistorted signal is provided as an input to the upconverter, wherein the filter is configured to reduce out-of-band noise generated by the predistorter,wherein the programmable filter comprises:na first programmable capacitor having a first terminal connected to a voltage reference, and a second terminal connected to a first input of the upconverter;a first programmable resistor having a first terminal connected to a first output of the predistorter, and a second terminal connected to the first input of the upconverter;a second programmable capacitor having a first terminal connected to the voltage reference, and a second terminal connected to a second input of the upconverter; anda second programmable resistor having a first terminal connected to a second output of the predistorter, and a second terminal connected to the second input of the upconverter.

An apparatus comprising:nan upconverter comprising at least one transistor;an analog predistorter configured to receive an input signal and to generate a predistorted signal that at least partially corrects non-linearity of the at least one transistor of the upconverter; anda filter disposed in a signal path between the predistorter and the upconverter, wherein the filter is configured to filter the predistorted signal to generate a filtered predistorted signal, wherein the filtered predistorted signal is provided as an input to the upconverter, wherein the filter is configured to reduce out-of-band noise generated by the predistorter,wherein the at least one transistor of the upconverter further comprises:na first transistor having a gate coupled to a filtered version of a first output of the predistorter, a source connected to a second voltage reference, and a drain;a second transistor having a gate electrically connected to a non-inverted oscillator signal, a source electrically connected to the drain of the first transistor, and a drain electrically connected to the first output node;a third transistor having a gate electrically connected to an inverted oscillator signal, a source electrically connected to the drain of the first transistor, and a drain electrically connected to the second output node;a fourth transistor having a gate coupled to a filtered version of a second output of the predistortion stage, a source connected to the second voltage reference, and a drain;a fifth transistor having a gate connected to the non-inverted oscillator signal, a source electrically connected to the drain of the fourth transistor, and a drain electrically connected to the second output node; anda sixth transistor having a gate electrically connected to the second oscillator input, a source electrically connected to the drain of the fourth transistor, and a drain electrically connected to the first output node.

A method of processing a signal comprising:npredistorting an analog signal to generate a predistorted signal, wherein the predistorted signal at least partially compensates for non-linearity of a transistor;filtering the predistorted signal to generate a filtered signal; andupconverting the filtered signal, wherein the transistor to be compensated is used in upconverting,wherein predistorting comprises operating a replica transistor in a feedback loop to generate a predistorted gate signal as the predistorted signal, and wherein upconverting comprises applying the filtered signal as a gate drive to a transistor that is a scaled version of the replica transistor.

An apparatus for processing a signal, the apparatus comprising:nmeans for predistorting a signal to generate a predistorted signal, wherein the predistorted signal at least partially compensates for non-linearity of a transistor;means for filtering the predistorted signal to generate a filtered signal; andmeans for upconverting the filtered signal, wherein the upconverting means comprises the transistor to be compensated,wherein the means for predistorting comprises means for operating a replica transistor in a feedback loop to generate a predistorted gate signal as the predistorted signal, and wherein means for upconverting comprises means for applying the filtered signal as a gate drive to a transistor that is a scaled version of the replica transistor.