Microphone Active Vibration Noise Cancellation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional microphones fail to effectively counteract noise caused by undesired vibrations, as the damping units can only partially absorb the energy, leading to significant noise signals when the vibrations are large.
Innovation Solution
The microphone design incorporates a capsule module with both a primary and secondary transducer unit, where the secondary transducer converts vibrations into electrical signals of opposite polarity, which are then processed to cancel out the noise signal, using a processing circuit to counteract the noise.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-affected harmful factors
If a damping unit is used to absorb vibration energy, then the amplitude of vibration wave is decreased, but significant noise signals remain when vibration amplitude is large
Solution Approach 1:
The patent converts the harmful vibration energy into a useful function by using a secondary transducer to detect vibration signals and generate anti-phase electrical signals that actively cancel the noise. This transforms the harmful vibration into a beneficial noise-cancellation mechanism, resolving the limitation of passive damping units that cannot fully eliminate noise under large vibrations.
Solution Approach 2:
The patent implements a feedback mechanism where the secondary transducer continuously monitors vibration signals, the processing circuit generates anti-phase signals based on this feedback, and these signals are combined with the primary audio signal to actively cancel noise. This closed-loop feedback system ensures effective noise counteraction across varying vibration amplitudes, overcoming the passive damping unit's inability to adapt to large vibrations.
2Device complexity
If a conventional dynamic microphone capsule is used, then the structure is simple, but it cannot effectively distinguish between sound waves and vibration noise
Solution Approach 1:
The patent segments the transducer function into two independent units: a primary transducer for capturing sound waves and a secondary transducer for detecting vibration noise. This segmentation allows each transducer to specialize in its specific function, enabling precise discrimination between sound signals and vibration noise while maintaining manageable structural complexity through modular design.
Solution Approach 2:
The patent creates a multi-functional transducer system where the primary transducer handles audio signal capture and the secondary transducer handles vibration detection and noise cancellation. This universal approach allows the microphone to simultaneously perform multiple functions (sound capture, vibration detection, noise cancellation) with enhanced measurement precision while keeping the overall structure organized and manageable.
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 design significantly reduces noise signals attributed to vibrations, improving sound quality by actively counteracting the noise, as evident in the frequency response diagrams showing reduced noise magnitude in the described embodiments.
Implementation Method 1
a first diaphragm that is configured for converting the sound waves and the vibration into first mechanical motion
Implementation Method 2
a primary transducer that is connected to and covered by the first diaphragm for converting the first mechanical motion into a first electrical signal
Implementation Method 3
a second diaphragm that is configured for converting the vibration into second mechanical motion
Implementation Method 4
a secondary transducer that is connected to and covered by the second diaphragm for converting the second mechanical motion into a second electrical signal
Implementation Method 5
the second secondary electrical signal counteracts the first secondary electrical signal when the processing circuit receives the first and second electrical signals
Data Source
AI summary
A microphone includes a capsule module including a carrier, a primary transducer unit and a secondary transducer unit. The carrier includes a hollow part mounted to a handle unit, and first and second carrier parts extending oppositely from the hollow part. The primary transducer unit is mounted to the first carrier part, and converts sound waves and vibration into a primary electrical signal a first secondary electrical signal, respectively. The secondary transducer unit is mounted to the second carrier part, and converts the vibration into a second secondary electrical signal for counteracting the first secondary electrical signal. The secondary transducer unit includes a diaphragm disposed within an airtight space.