Vehicle Sound Reproduction Using HRTF and Microphone Arrays
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Users experience differences between recorded and original sounds due to the use of a single microphone, variations in microphone sensitivity, and the influence of head and ear shapes, as well as sound reflection and diffraction, which affect the reproduction space.
Innovation Solution
A vehicle system equipped with multiple microphones, a sensor module, and a controller that modulates sound signals based on microphone sensitivity, relative positions, and Head-Related Transfer Function (HRTF) to equalize sound intensities and remove reverberation, ensuring a sound output similar to the original.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Device complexity
If a single microphone is used to record sound, then the device complexity is reduced, but the sound quality and fidelity deteriorate because the recorded sound differs from the original sound
Solution Approach 1:
The patent divides the sound recording function into multiple microphones positioned at different locations (e.g., left and right ear positions). Each microphone captures sound from its specific position, and the controller processes these separate signals to reconstruct the original sound field, thereby improving sound fidelity while maintaining reasonable device complexity
Solution Approach 2:
The patent combines signals from multiple microphones in the controller to create a composite sound output that replicates the original sound. By merging the information from multiple recording positions and applying HRTF processing, the system achieves high-fidelity sound reproduction that neither single microphone could achieve alone
2Manufacturing precision
If multiple microphones are used to improve sound recording accuracy, then the sound fidelity improves, but the device complexity increases
Solution Approach 1:
The patent positions microphones at specific locations that correspond to human ear positions (left and right). Each microphone is strategically placed to capture sound characteristics relevant to its position, creating a natural stereo image that improves recording accuracy without requiring excessive microphones throughout the entire space
Solution Approach 2:
The controller performs multiple functions: it receives signals from multiple microphones, applies HRTF processing, compensates for sensitivity differences, and outputs the processed sound. This multi-functional approach consolidates complex processing into a single control unit, managing device complexity while maintaining high recording accuracy
3Ease of operation
If microphone sensitivity differences are not compensated, then the system operation is simpler, but the sound intensity balance deteriorates
Solution Approach 1:
The controller receives sensitivity information for each microphone and uses this feedback to adjust the gain of each channel. By continuously monitoring and compensating for sensitivity differences, the system maintains balanced sound intensity across all microphones, ensuring accurate sound reproduction without requiring manual calibration
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 replicates the original sound by adjusting sound intensities and convolving HRTF, providing a more immersive listening experience by accounting for user physical characteristics and vehicle states.
Implementation Method 1
The controller is configured to modulate the sound signal having two channels based on at least one of the sensitivity of each microphone of the plurality of microphones, the relative position between the plurality of microphones, and a Head-Related Transfer Function (HRTF)
Implementation Method 2
The controller is further configured to remove the reverberation corresponding to the state of the vehicle from the modulated sound signal
Data Source
AI summary
A vehicle and a method of controlling the vehicle are capable of outputting a sound similar to an original sound by modulating a sound signal obtained using a plurality of microphones of an external terminal device considering the physical characteristics of a user and the sound reproduction space. The vehicle includes: a speaker; a sensor module configured to detect a state of the vehicle; a communicator including a plurality of microphones and configured to receive a sound signal having two channels, information about sensitivity of each microphone of the plurality of microphones, and information about a relative position between the plurality of microphones; and a controller configured to: modulate the sound signal on at least one of the sensitivity of the plurality of microphones, the relative position between the plurality of microphones, and a Head-Related Transfer Function (HRTF); remove the reverberation from the modulated sound signal; and control the speaker.