Air Pulse Sound System Multipath Reconstruction
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional speaker systems face challenges in producing high-fidelity sound across the full range of human audible frequencies due to the need for multiple drivers and enclosures, which increase size and cost, and fail to effectively utilize the multipath effect to reconstruct sound at listener locations.
Innovation Solution
A sound producing system that utilizes a sound producing device to generate air pulses at a rate higher than human audible frequency, leveraging the multipath effect by employing a time-reversal signal transmission technique to reconstruct audible sound directly at listener locations, eliminating the need for enclosures to contain back-radiating waves and reducing sound pressure levels.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If multiple drivers (tweeters, mid-range drivers, woofers) are incorporated to cover full audible frequency range, then frequency coverage is improved, but device complexity and size increase
Solution Approach 1:
A single sound producing device is designed to perform multiple functions by generating air pulses that can be modulated to cover the full audible frequency range, replacing the need for separate tweeters, mid-range drivers, and woofers. The device achieves universal frequency coverage through pulse modulation techniques rather than requiring multiple specialized drivers.
2Adaptability or versatility
If speaker enclosure is used to contain back-radiating wave, then low-frequency response is improved, but device volume increases
Solution Approach 1:
The invention extracts and eliminates the enclosure component from the traditional speaker system. By using air pulse generation and modulation, the system achieves improved low-frequency response without requiring a physical enclosure to contain back-radiating waves, thereby removing the volume constraint entirely.
3Manufacturing precision
If enclosure is used to reshape low-frequency response, then sound quality is improved, but loss of energy increases due to containing back-radiating wave
Solution Approach 1:
Instead of containing and managing back-radiating waves as in traditional enclosures, the invention converts the energy that would be wasted into useful sound production by generating directed air pulses. The system transforms what would be harmful energy loss into beneficial acoustic output, achieving improved sound quality without energy waste.
4Device complexity
If sound is produced at surface of sound producing device, then device simplicity is maintained, but sound pressure level at listening position is insufficient
Solution Approach 1:
The system performs preliminary action by generating high-frequency air pulses that propagate through the environment before reaching the listening position. These pulses are modulated to construct the desired sound pressure level envelope at the target location, allowing sufficient SPL at the listening position while maintaining device simplicity.
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 achieves efficient sound production with reduced sound pressure levels and increased efficiency by utilizing the multipath environment to reconstruct sound close to listeners, eliminating the need for enclosures and improving sound production efficiency.
Implementation Method 1
the PAM-UPA sound producing scheme does not take 'multipath effect' into consideration
Data Source
Figure 1
Figure 2
Figure 3
AI summary
A sound producing apparatus (12) is provided. The sound producing apparatus (12) includes a sound producing device (120) disposed at a sound producing location and configured to produce a plurality of air pulses according to a driving signal; a driving circuit (122), configured to generate the driving signal according to an input audio signal (A(t)), wherein the plurality of air pulses is emitted from the sound producing location (LSP), propagates through an environment, such that a sound pressure level (SPL) envelope corresponding to the input audio signal (A(t)) is constructed at a sound construction location (LSC); wherein the sound construction location (LSC) is different from the sound production location (LSP).