Transmitter architecture and related methods

摘要

A radio frequency (RF) transmitter includes one or more power amplifiers and a controller that is configured to adjust amplitudes and phases of RF input signals of the one or more power amplifiers and supply voltages applied to the one or more power amplifiers. In embodiments where multiple power amplifiers are used, a combiner may be provided to combine outputs of the power amplifiers. In at least one implementation, amplitude adjustment of the RF input signals of the one or more power amplifiers may be used to provide transmit power control and/or power backoff for the RF transmitter.

主权项

1. A radio frequency (RF) transmitter, comprising:
a first RF power amplifier; a second RF power amplifier; a combiner to combine output signals of the first and second RF power amplifiers; a first digital-to-RF modulator to generate an RF input signal for the first RF power amplifier based on first information indicative of a first amplitude and a first phase; a second digital-to-RF modulator to generate an RF input signal for the second RF power amplifier based on second information indicative of a second amplitude and a second phase; a first voltage control unit to provide a variable supply voltage to the first RF power amplifier in response to a first control signal; a second voltage control unit to provide a variable supply voltage to the second RF power amplifier in response to a second control signal; and a controller configured to:
receive data indicative of a vector to be transmitted from the transmitter;select first and second voltage levels for the first and second power amplifiers, respectively, that are capable of providing the vector at the output of the combiner;select first and second input phase angles for the first and second power amplifiers, respectively, to achieve the vector at the output of the combiner;select first and second input amplitude levels to be provided to the first and second power amplifiers, respectively, to achieve the vector at the output of the combiner, wherein at least one of the first input amplitude level and the second input amplitude level are such that the corresponding power amplifier is backed off from a saturation point associated with the voltage level selected for that power amplifier; andgenerate the first information based on the first input phase angle and the first input amplitude level, generate the second information based on the second input phase angle and the second input amplitude level, generate the first control signal based on the first selected voltage level, and generate the second control signal based on the second selected voltage level, thereby setting an output power level of the RF transmitter.