Continuous Wave Radar Phase Spectrum Detection

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Continuous wave radar detectors face limitations in determining distances and relative speeds with high performance and low false alarm rates, as they primarily rely on amplitude information and lack effective utilization of phase data.

Innovation Solution

A method that involves generating multiple partial transmission signals with specific criteria differences, such as frequency, polarization, or time, and complexly mixing these with received signals to generate phase spectra for comparison, allowing for the detection of objects based on statistical features like variance, thereby incorporating phase information for improved detection.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If continuous wave radar detectors rely primarily on amplitude information for object detection, then the detection process is simple, but the detection performance and accuracy are limited with high false alarm rates

Engineering Contradiction:
Improvedetection accuracyVSAvoidsignal processing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The transmission signal is segmented into multiple partial transmission signals with different frequency offsets. Each partial signal is processed separately to generate phase spectra, which are then combined to improve detection accuracy. This segmentation allows the system to extract more information from the signal while maintaining manageable processing complexity through parallel processing of multiple simpler signals.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The invention transitions from one-dimensional amplitude-based detection to two-dimensional detection by incorporating phase information across multiple frequency offsets. By adding the phase dimension and frequency offset dimension, the system achieves superior detection performance and false alarm rejection without proportionally increasing processing complexity.

Inventive Principle:
Principle #17Another dimension (Dimensionality change)

2Reliability

If phase information is incorporated into the detection process, then detection performance improves with lower false alarm rates, but the signal processing complexity increases

Engineering Contradiction:
Improvefalse alarm rateVSAvoidsignal processing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The signal processing is segmented into multiple independent channels, each handling a specific frequency offset. By processing multiple simplified phase spectra in parallel rather than one complex spectrum sequentially, the system achieves reliable detection with reduced false alarms while keeping individual processing tasks manageable.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Multiple phase spectra from different frequency offsets are merged to form a composite detection result. This merging process combines the reliability benefits of phase information across multiple frequencies while distributing the processing load, thereby improving false alarm rejection without concentrating all complexity in a single processing step.

Inventive Principle:
Principle #5Merging (Combining)

3Measurement precision

If multiple partial transmission signals with different frequency offsets are transmitted and processed, then detection accuracy improves, but the device complexity and computational requirements increase

Engineering Contradiction:
Improvedistance and speed determination accuracyVSAvoidnumber of signal processing channels
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The detection task is segmented across multiple frequency offset channels, with each channel processing a simplified version of the signal. This segmentation improves measurement precision by providing multiple independent measurements that can be combined, while the modular structure keeps individual processing channels simple and manageable.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Each partial transmission signal and its corresponding processing channel serves multiple functions: it contributes to distance measurement, speed measurement, and false alarm rejection simultaneously. This multi-functionality allows the system to achieve high detection accuracy without proportionally increasing device complexity, as the same processing infrastructure serves multiple detection objectives.

Inventive Principle:
Principle #6Universality (Multi-functionality)

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

This approach enhances the detection performance of continuous wave radar detectors by reducing false alarms and increasing detection rates, particularly at low signal-to-noise ratios, by effectively utilizing phase data to identify objects with improved accuracy.

Implementation Method 1

A continuous wave radar detector, hereinafter also referred to as 'continuous wave radar' for short, is a radar system with a transmitter and a receiver, in which the transmitter emits a high-frequency electromagnetic wave in the direction of a monitoring area. If the electromagnetic wave hits an object, a small part of the transmission power is reflected back to the continuous wave radar detector as an echo signal and registered there by the receiver.

Methodology Applied
Scientific EffectRadar: Radar

Implementation Method 2

The speed measurement with a continuous wave radar is based on the exploitation of the Doppler effect. The transmitted signal is reflected by an object because of the Doppler effect around the Doppler frequency shifted and arrives at the receiver of the continuous wave radar detector after a distance-dependent transit time.

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Implementation Method 3

A distance can also be determined with a frequency-modulated continuous wave radar, also known as FMCW radar mentioned, can be carried out. With such FMCW radars, the transmission frequency is changed periodically.

Methodology Applied
Scientific EffectFrequency modulation: Phase Modulation

Implementation Method 4

In FMCW radar systems, the propagation time leads to an additional frequency shift of the received signal compared to the current transmission frequency by a distance-dependent frequency.

Methodology Applied
Scientific EffectTime of flight: Time of Flight

Data Source

PatentEP3064960B1Method for operating a permanent line radar detector and permanent line radar detector
Publication Date: 2018.08.15 SICK AG
  • EP3064960B1 patent drawingFigure 1~3
  • EP3064960B1 patent drawingFigure 4~6
  • EP3064960B1 patent drawingFigure 7~8

AI summary

The present invention relates to a method for determining information about distances and/or relative velocities of objects using a continuous-wave radar detector, in which: - an original transmitted signal is multiplied to generate several partial transmitted signals from the original transmitted signal, which differ from one another with respect to a predetermined criterion; - the multiplied transmitted signal comprising the partial transmitted signals is transmitted; - a transmitted signal reflected from an object is received as a received signal, wherein the received signal comprises several partial received signals which are assigned to the respective partial transmitted signals; - each partial transmitted signal is complexly mixed with the received signal, so that for each partial transmitted signal a respective complex subspectroscopy is generated with an amplitude spectrum having the real component and a phase spectrum having the imaginary component.- a comparison of the phase spectra for several different frequency values ​​is carried out, and - if necessary, a detection signal is generated, wherein the generation of the detection signal includes generating a phase detection signal if the comparison of the phase spectra shows that a predetermined phase detection criterion for the detection of an object is met.