Multi-Tone Siren Detection via Frequency Component Analysis

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing siren detection methods for automated vehicles are not robust in real-world conditions due to environmental noise, such as vehicle sounds and traffic, which makes it difficult to accurately recognize approaching emergency vehicles.

Innovation Solution

A system and method that processes frequency components of an acoustic signal to detect multi-tone sirens by accounting for doppler shifts and using explicit models of siren signals, which factor in tone duration and frequency changes, and employs integral signal representations to minimize interference from other tonal signals like speech and music.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If traditional siren detection methods are used, then the system can detect sirens in ideal conditions, but the detection reliability deteriorates in noisy real-world environments

Engineering Contradiction:
Improvesiren detection reliabilityVSAvoidenvironmental noise interference
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The acoustic signal is divided into multiple frequency components through Fourier transform, and each frequency component is processed independently to detect specific siren patterns. This segmentation allows the system to isolate siren signals from background noise by analyzing individual frequency bands rather than the entire spectrum at once.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system accounts for Doppler shifts by dynamically adjusting the expected frequency parameters of siren patterns based on the relative motion between the automated vehicle and emergency vehicles. This parameter adaptation allows accurate detection even when siren frequencies are shifted due to motion, maintaining reliability in real-world conditions.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If the system processes all frequency components in detail, then detection precision improves, but computational complexity increases

Engineering Contradiction:
Improvesiren detection precisionVSAvoidsignal processing complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The system performs a preliminary Fourier transform to convert the time-domain acoustic signal into frequency components before detailed analysis. This preliminary transformation organizes the signal data in a way that facilitates efficient pattern matching and reduces the computational burden of subsequent detection operations.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

Instead of analyzing all possible frequency components with equal detail, the system focuses computational resources on frequency ranges and time patterns where siren signals are most likely to occur. By applying detection algorithms selectively to relevant portions of the frequency spectrum, the system achieves high precision without requiring exhaustive processing of the entire signal.

Inventive Principle:
Principle #16Partial or excessive action

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 system effectively detects multi-tone sirens at low signal-to-noise ratios and distinguishes them from other sounds, enabling automated vehicles to respond appropriately to emergency vehicles even in noisy environments.

Implementation Method 1

A system and method that processes frequency components of an acoustic signal to detect multi-tone sirens by accounting for doppler shifts and using explicit models of siren signals, which factor in tone duration and frequency changes

Methodology Applied
Scientific EffectDoppler effect: Doppler Effect

Data Source

PatentUS20220363261A1System and method for acoustic detection of emergency sirens
Publication Date: 2022.11.17 CERENCE OPERATING CO
  • US20220363261A1 patent drawing
  • US20220363261A1 patent drawing
  • US20220363261A1 patent drawing

AI summary

A method detects presence of a multi-tone siren type in an acoustic signal. The multi-tone siren type is associated with one or more siren patterns, where each siren pattern includes a number of time patterns at corresponding frequencies. The method includes processing a number of frequency components of a frequency domain representation of the acoustic signal over time to determine a corresponding plurality of values. That processing includes determining, for each frequency component, a value characterizing a presence of a time pattern associated with at least one siren pattern. The method also includes processing the values according to the siren patterns to determine a detection result indicating whether the multi-tone siren type is present in the acoustic signal.