Adjustable power splitter and corresponding methods and apparatus

An adjustable radio frequency power splitter comprising:

• a power splitter input;
• a first power splitter output;
• a second power splitter output;
• a power divider with a power divider input coupled to the power splitter input, a first divider output, and a second divider output;
• a first adjustable phase shifter coupled to the first divider output;
• a first adjustable attenuator coupled to the first divider output and series coupled with the first adjustable phase shifter, wherein the first adjustable phase shifter and the first adjustable attenuator are configured to provide a first output signal at the first power splitter output;
• a second adjustable phase shifter coupled to the second divider output;
• a second adjustable attenuator coupled to the second divider output and series coupled with the second adjustable phase shifter, wherein the second adjustable phase shifter and the second adjustable attenuator are configured to provide a second output signal at the second power splitter output;
• an interface that includes a data in line, a data out line, a clock signal line, and a chip select line;
• and
• a controller configured to receive, via the interface, data indicating phase shifts to be applied by the first and second adjustable phase shifters and attenuation levels to be applied by the first and second adjustable attenuators, and to control, based on the data, the phase shifts and attenuation levels applied by the first and second adjustable phase shifters and the first and second adjustable attenuators.

An adjustable radio frequency power splitter comprising:

• a power splitter input;
• a first power splitter output;
• a second power splitter output;
• a power divider with a power divider input coupled to the power splitter input, a first divider output, and a second divider output;
• a first adjustable phase shifter coupled to the first divider output;
• a first adjustable attenuator coupled to the first divider output and series coupled with the first adjustable phase shifter, wherein the first adjustable phase shifter and the first adjustable attenuator are configured to provide a first output signal at the first power splitter output;
• a second adjustable phase shifter coupled to the second divider output;
• a second adjustable attenuator coupled to the second divider output and series coupled with the second adjustable phase shifter, wherein the second adjustable phase shifter and the second adjustable attenuator are configured to provide a second output signal at the second power splitter output;
• a fixed phase shifter configured for adding a fixed phase shift between first and second signals at the first and second power splitter outputs, respectively;
• an interface;
• and
• a controller configured to receive, via the interface, data indicating phase shifts to be applied by the first and second adjustable phase shifters and attenuation levels to be applied by the first and second adjustable attenuators, and to control, based on the data, the phase shifts and attenuation levels applied by the first and second adjustable phase shifters and the first and second adjustable attenuators.

An adjustable power splitter with a Doherty amplifier comprising:

• a power input;
• a first power output;
• a second power output;
• a power divider with a power divider input coupled to the power input, a first divider output, and a second divider output;
• a first adjustable phase shifter coupled to the first divider output;
• a first adjustable attenuator coupled to the first divider output and series coupled with the first adjustable phase shifter, wherein the first adjustable phase shifter and the first adjustable attenuator are configured to provide a first output signal at the first power output;
• a second adjustable phase shifter coupled to the second divider output;
• a second adjustable attenuator coupled to the second divider output and series coupled with the second adjustable phase shifter, wherein the second adjustable phase shifter and the second adjustable attenuator are configured to provide a second output signal at the second power output;
• an interface;
• a controller configured to receive, via the interface, data indicating phase shifts to be applied by the first and second adjustable phase shifters and attenuation levels to be applied by the first and second adjustable attenuators, and to control, based on the data, the phase shifts and attenuation levels applied by the first and second adjustable phase shifters and the first and second adjustable attenuators;
• and
• a radio frequency Doherty power amplifier with a main amplifier coupled to the first power output and a first peaking amplifier coupled to the second power output.

A method of adjusting a power split signal comprising:

• splitting an input signal into first and second signals at first and second divider outputs;
• receiving, through an interface, data indicating phase shifts to be applied by first and second adjustable phase shifters and attenuations to be applied by first and second adjustable attenuators, wherein the first adjustable phase shifter and the first adjustable attenuator are series coupled between the first divider output and a first power output, and the second adjustable phase shifter and the second adjustable attenuator are series coupled between the second divider output and a second power output;
• controlling, based on the data, the states of the first and second adjustable phase shifters and the first and second adjustable attenuators to realize the phase shifts and the attenuations indicated in the data;
• adjusting, by the first adjustable phase shifter and the first adjustable attenuator, a phase shift and attenuation of the first signal to provide a first resultant signal at the first power output to a first amplifier;
• and
• adjusting, by the second adjustable phase shifter and the second adjustable attenuator, a phase shift and attenuation of the second signal to provide a second resultant signal at the second power output to a second amplifier.