US 12,638,579 B2Granted

Radar power calibration with mismatch compensation

AssigneeNXP B.V.

InventorsMohamad El Ozeir, Cristian Pavao Moreira, Pierre Pascal Savary

Life of this patent

Estimating the term…

Loading patent…

Abstract

A first input signal that corresponds to an output transmitted signal of a power amplifier of a vehicle radar system is received and the output power level of the transmitted signal is calibrated to optimize quality of the transmitted signal at the antenna reference plane (ARP). The proposed calibration method and apparatus allows to improve the output power calibration accuracy at ARP by compensating for reflected power at power amplifier output. The proposed apparatus uses the coupled and the isolated outputs of a bi-directional coupler to compensate the mismatch between the output of the power amplifier and the ARP; detectors at both coupler outputs measure both powers (coupled, isolated output) and apply respective correction on the calibration target to compensate for reflected power.

Claims20

Dependent claims

A system for a vehicle radar subsystem, the system comprising:

a power amplifier configured to generate a first output signal at an output terminal of the power amplifier;
a coupler electrically connected to the output terminal of the power amplifier, the coupler configured to output:
at an output port of the coupler, a second output signal that corresponds to the first output signal;
at a coupled port of the coupler, a coupled output signal corresponding to a coupled portion of the first output signal coupled within the coupler, the coupled output signal also corresponding to an amount of incident power at an antenna reference plane (ARP) of the vehicle radar subsystem;
and
at an isolated port of the coupler, an isolated output signal corresponding to an amount of reflected power at the output terminal of the power amplifier;
a first detector electrically connected to the coupled port of the coupler, the first detector configured to produce a first detector signal responsive to the coupled output signal power level;
a second detector electrically connected to the isolated port of the coupler, the second detector configured to produce a second detector signal responsive to the isolated output signal power level;
and
a controller in electrical communication with the power amplifier and the first and second detectors, the controller configured to execute control logic that causes the controller to:
perform an initial calibration comprising controlling the power amplifier to generate the first output signal at a first calibrated power level based on an initial calibration target and the first detector signal;
subsequent to the initial calibration, modify the initial calibration target using the second detector signal and an offset associated with one or both of the coupler and the second detector, to produce an updated calibration target;
and
perform a compensated calibration comprising controlling the power amplifier to generate the first output signal at a second calibrated power level based on the updated calibration target and the first detector signal.

11 more elements

A method, comprising:

receiving a first input signal that corresponds to a measured power level of an output signal of a power amplifier of a vehicle radar system;
controlling the power amplifier to iteratively increase or decrease an output power level of the output signal until the output power level reaches a first calibrated output power at which the first input signal matches an initial calibration target;
receiving a second input signal that corresponds to a measurement of reflected power at an output port of the power amplifier when the output signal has the first calibrated power level;
determining, based on the measurement of the reflected power, a compensation value;
adding the compensation value to the initial calibration target to produce an updated calibration target;
and
controlling the power amplifier to increase or decrease the output power level of the output signal until the output power level reaches a second calibrated output power at which the first input signal matches the updated calibration target.

4 more elements

A system for a vehicle radar subsystem, the system configured to:

receive a first input signal that corresponds to a measured power level of an output signal of a power amplifier;
iteratively increase or decrease an output power level of the output signal until the output power level reaches a first calibrated output power at which the first input signal matches an initial calibration target;
receive a second input signal that corresponds to a measurement of reflected power at an output port of the power amplifier when the output signal has the first calibrated power level;
determine a compensation value based on the measurement of the reflected power;
add the compensation value to the initial calibration target to produce an updated calibration target;
and
increase or decrease the output power level of the output signal until the output power level reaches a second calibrated output power at which the first input signal matches the updated calibration target.

4 more elements

Dependencies are inferred from the claim text.