Power amplifier with nulling monitor circuit
AssigneeAnalog Devices, Inc.
InventorChristopher John Day
Life of this patent
Estimating the term…
Abstract
Techniques for monitoring a distortion signal of a power amplifier circuit, where the output of a distortion monitoring circuit includes little or no fundamental signal and closely represents the actual distortion of the amplifier circuit of a wired communications system. The power amplifier circuit can generate a distortion feedback signal that does not affect the power amplifier's output power capability, e.g., no inherent loss in the fundamental output of the amplifier. That is, using a distortion monitor circuit, the power amplifier circuit can resolve a distortion feedback signal from the intended output signal of the output power amplifier circuit.
Claims20
A method of reducing an amount of distortion in an output signal of a power amplifier circuit in a wired communication network, the method comprising:
- receiving an input signal at an input of the power amplifier circuit;
- using a distortion monitoring circuit in the power amplifier circuit, generating a distortion feedback signal resolved from an intended output signal at a first output of the power amplifier circuit, wherein the distortion monitoring circuit includes two resistor networks, the two resistor networks including:
- a first resistor network and a second resistor network coupled to terminals of first and second transistors that are coupled to the input of the power amplifier circuit;
- or
- a third resistor network and a fourth resistor network coupled in corresponding feedback paths between the input and the first output;
- and
- generating the output signal from the intended output signal at a second output of the power amplifier circuit.
A power amplifier circuit configured to reduce an amount of distortion in an output signal in a wired communication network, the power amplifier circuit comprising:
- an input to receive an input signal;
- a distortion monitoring circuit configured to generate and output a distortion feedback signal resolved from an intended output signal at a first output, wherein the distortion monitoring circuit includes two resistor networks, the two resistor networks:
- a first resistor network and a second resistor network coupled to terminals of first and second transistors that are coupled to the input of the power amplifier circuit;
- or
- a third resistor network and a fourth resistor network coupled in corresponding feedback paths between the input and the first output;
- and
- a second output to provide the output signal.
A power amplifier circuit configured to reduce an amount of distortion in an output signal in a wired communication network, the power amplifier circuit comprising:
- means for receiving an input signal at an input of the power amplifier circuit;
- means for generating a distortion feedback signal resolved from an intended output signal at a first output of the power amplifier circuit, wherein the means for generating the distortion feedback signal includes two resistor networks, the two resistor networks including:
- a first resistor network and a second resistor network coupled to terminals of first and second transistors that are coupled to the input of the power amplifier circuit;
- or
- a third resistor network and a fourth resistor network coupled in corresponding feedback paths between the input and the first output;
- and
- means for generating the output signal from the intended output signal at a second output of the power amplifier circuit.
Dependencies are inferred from the claim text.