Automotive Radar Interference Suppression With Recursive Thresholding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Automotive radar systems face interference challenges due to multiple interference signals with varying power levels, leading to degraded detection performance as conventional thresholding techniques struggle to accurately suppress interference, often missing weak signals or misidentifying strong peaks.

Innovation Solution

Implementing a recursive thresholding process that determines a threshold value based on previous chirp data, using a min-max operation to estimate a predicted threshold, combined with time or time-frequency domain analysis, to enhance interference suppression in complex scenarios without increasing latency.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional thresholding techniques are used for interference suppression, then the processing speed is maintained, but the detection precision deteriorates due to inability to accurately suppress interference with varying power levels

Engineering Contradiction:
Improvedetection precisionVSAvoidprocessing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent implements dynamic thresholding where the interference threshold is continuously adapted based on the power levels of detected interference signals. The thresholding mechanism adjusts its parameters in real-time to match the varying interference conditions, enabling accurate suppression across different power levels while maintaining processing efficiency through algorithmic optimization.

Inventive Principle:
Principle #15Dynamics

Solution Approach 2:

The patent changes the thresholding parameters dynamically based on the detected interference characteristics. By monitoring interference power levels and adjusting the threshold parameters accordingly, the system achieves high detection precision for both weak and strong interference signals without requiring complex processing architectures.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If aggressive thresholding is applied to suppress strong interference, then interference suppression improves, but weak radar signals are missed leading to reduced detection accuracy

Engineering Contradiction:
Improveinterference suppression accuracyVSAvoidsignal detection reliability
Core Design Contradiction:
Measurement precisionVSReliability

Solution Approach 1:

The patent applies local quality by using adaptive thresholding that adjusts its aggressiveness based on the local signal characteristics. In regions with strong interference, the threshold is set to suppress interference effectively, while in regions with weak signals, the threshold is adjusted to preserve signal integrity. This localized adaptation ensures both interference suppression accuracy and signal detection reliability.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The thresholding mechanism dynamically adapts its parameters based on the detected signal and interference characteristics. The system continuously monitors the power levels and adjusts the thresholding aggressiveness in real-time, enabling effective suppression of strong interference while maintaining sensitivity to weak radar signals through dynamic parameter adjustment.

Inventive Principle:
Principle #15Dynamics

3Measurement precision

If multiple thresholding passes are performed to improve interference suppression, then detection accuracy improves, but processing latency increases

Engineering Contradiction:
Improvedetection accuracyVSAvoidprocessing latency
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The patent performs preliminary action by conducting interference thresholding before range-Doppler processing. By suppressing interference early in the signal processing chain, the system achieves high detection accuracy in subsequent processing stages without requiring multiple thresholding passes, thereby minimizing processing latency while maintaining improved detection performance.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent segments the signal processing into distinct stages: interference thresholding, range processing, and Doppler processing. By performing interference suppression as a separate preliminary stage with optimized algorithms, the system achieves high detection accuracy without introducing excessive latency in the overall processing pipeline.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP4686957A1Automotive radar system with interference suppression
Publication Date: 2026.02.04 NXP BV
  • EP4686957A1 patent drawingFigure 1
  • EP4686957A1 patent drawingFigure 2
  • EP4686957A1 patent drawingFigure 3

AI summary

The present disclosure relates to a radar system having signal processing circuitry configured to receive sets of samples each representing a respective reflected radar signal and to generate sets of interference-suppressed samples including a first set of interference-suppressed samples corresponding to a first reflected radar signal represented by a first set of samples. To generate the first set of interference-suppressed samples, the signal processing circuitry may determine a first threshold based on at least one previously determined threshold for at least a second set of samples of the sets of samples, determine a second threshold based on the first set of samples, determine a third threshold as an average of the first threshold and the second threshold, and apply the third threshold to the first set of samples to remove or suppress interference components of the first set of samples to generate the first set of interference-suppressed samples.