Radar Transceiver Phase-Noise Cancellation via Quadrature Feedback
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Radar systems face significant degradation in signal-to-noise ratio (SNR) due to strong reflectors like vehicle bumpers, which introduce uncorrelated phase noise and limit detection range, and existing compensation methods fail to effectively cancel frequency and phase shifts caused by reflector movement.
Innovation Solution
An analog control loop in the quadrature channel of the radar receiver is implemented to cancel frequency and phase shifts induced by strong reflectors, using a phase shifter and feedback path to maintain an amplitude noise condition, thereby improving SNR.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If radar systems operate in the presence of strong reflectors, then detection capability is maintained, but signal-to-noise ratio deteriorates due to uncorrelated phase noise
Solution Approach 1:
The patent implements a feedback mechanism where the quadrature channel detects phase noise introduced by strong reflectors, and this detection is fed back to control a phase shifter in the in-phase channel. This closed-loop feedback system dynamically compensates for phase variations, maintaining signal-to-noise ratio while preserving detection capability in the presence of strong reflectors.
Solution Approach 2:
The quadrature channel serves as an intermediary that measures the phase noise caused by strong reflectors. By using the quadrature channel as a mediator to detect and characterize the interference, the system can then apply appropriate compensation through the phase shifter without directly processing the corrupted in-phase signal.
2Measurement precision
If conventional radar receivers process signals with strong reflectors, then detection is performed, but detection range is limited due to phase noise
Solution Approach 1:
The feedback loop continuously monitors phase variations in the quadrature channel and adjusts the phase shifter accordingly, enabling the system to maintain detection accuracy over extended ranges despite the presence of strong reflectors that would otherwise limit detection range.
3Productivity
If strong reflectors are present in the radar environment, then signal reception continues, but detection accuracy deteriorates due to phase shifts
Solution Approach 1:
The system maintains continuous signal reception while preserving detection accuracy through real-time feedback control. The quadrature channel detects phase shifts caused by strong reflectors, and this information is immediately used to adjust the phase shifter, ensuring accurate detection continues without interruption despite the presence of strong reflectors.
Solution Approach 2:
The patent replaces mechanical or hardware-based phase stabilization methods with an electronic control system using phase shifters and feedback control. This substitution allows for dynamic, real-time compensation of phase variations without mechanical moving parts, maintaining both continuous reception and high detection accuracy.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The proposed solution enhances the SNR by up to 10 dB, effectively tracking and canceling frequency and phase variations from reflector vibrations, thus improving radar detection range and accuracy.
Implementation Method 1
apply a phase shift to the oscillating signal to generate a phase-shifted oscillating signal in response to a control signal
Implementation Method 2
mix the output signal with the amplified signal to generate a mixed signal
Implementation Method 3
apply a filter operation to the mixed signal to generate a filtered signal
Implementation Method 4
integrate the filtered signal to generate the control signal
Data Source
AI summary
A device, e.g., a radar transceiver, includes a receiver and a transmitter. One such device includes a phase shifter having a first input to receive an oscillating signal and a second input to receive a control signal. The device also includes a signal generator having a quadrature (Q) channel output to output a quadrature phase version of the oscillating signal; and a Q channel mixer having an input coupled to the Q channel output. A feedback path of the device includes a filter having an output and an input coupled to an output of the Q channel mixer, and an integrator having an input coupled to the output of the filter. The integrator has an output coupled to the second input of the phase shifter, in which the integrator outputs the control signal to the phase shifter.