Stepped-Chirp Radar Processing for Higher Range-Velocity Resolution

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing radar systems suffer from limited range and velocity resolution, which hinders accurate determination of target location and velocity.

Innovation Solution

A radar apparatus that processes frequency stepped series of chirps using autoregressive linear prediction, including Doppler FFT and Range FFT, to enhance down-range resolution and improve target detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If conventional radar signal processing is used, then the system is simple to operate, but the range and velocity resolution are limited

Engineering Contradiction:
Improverange and velocity resolutionVSAvoidsignal processing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies autoregressive linear prediction to extrapolate radar signal samples before performing FFT processing. This preliminary action on the signal data allows the system to achieve enhanced resolution by predicting future signal values based on past samples, effectively improving measurement precision without requiring additional hardware complexity

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent changes the processing approach by applying autoregressive prediction with specific order parameters (e.g., AR(2) or AR(3)) to the radar signal samples. By modifying the mathematical processing parameters rather than the physical system, the resolution is improved while keeping the device structure relatively simple

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If more radar samples are processed to improve resolution, then the measurement precision increases, but the processing time increases

Engineering Contradiction:
Improvedown-range resolutionVSAvoidprocessing time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The autoregressive linear prediction performs preliminary extrapolation on radar samples using a compact mathematical model. This allows the system to achieve the effect of processing more samples without actually collecting and processing a larger volume of data, thus improving resolution while minimizing additional processing time

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The patent creates a mathematical model (autoregressive prediction) that replicates the information content of additional radar samples. Instead of collecting more physical samples which would increase processing time, the system generates synthetic sample values through the prediction model, achieving enhanced resolution efficiently

Inventive Principle:
Principle #26Copying

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 combination of frequency stepped chirps with autoregressive linear prediction enhances down-range resolution, reducing the number of targets in Doppler bins and improving the accuracy of target position and velocity determination.

Implementation Method 1

receive radar data, the radar data comprising a plurality of samples representing the reflections of transmitted radar signals from one or more targets

Methodology Applied
Scientific EffectRadar: Radar

Implementation Method 2

calculate a Doppler FFT... determine one or both of a range and velocity of the one or more targets

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Implementation Method 3

the Doppler FFT is calculated based on the radar data by determining a Fourier transform of respective first-groups of the samples

Methodology Applied
Scientific EffectFourier transform:

Data Source

PatentEP4671808A1Radar apparatus
Publication Date: 2025.12.31 NXP BV
  • EP4671808A1 patent drawingFigure 1
  • EP4671808A1 patent drawingFigure 2~3
  • EP4671808A1 patent drawingFigure 4~5

AI summary

A radar apparatus comprising one or more processors configured to: receive radar data comprising a plurality of samples representing the reflections of transmitted radar signals from one or more targets having been received by one or more antennas, the transmitted radar signals comprising a series of frequency stepped chirps; calculate a Doppler FFT based on the radar data by determining a Fourier transform of respective first-groups of the samples of the plurality of samples, wherein each first-group comprises a sample from each of the chirps of the series of chirps from a corresponding time-point during the respective chirp, to generate Doppler-FFT data; perform autoregressive linear prediction, wherein said autoregressive linear prediction is respectively applied to the samples of each chirp as represented in the Doppler-FFT data to generate extrapolated Doppler-FFT data; perform further processing to determine range and/or velocity of the targets based on the extrapolated Doppler-FFT data.