Microphone Position Estimation via Correlation Signal Analysis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing audio rendering systems face challenges in accurately determining microphone positions during normal operation, especially in diverse acoustic environments, due to reliance on specific test signals and unpredictable audio properties, leading to unreliable position estimation.
Innovation Solution
A system comprising a multi-channel signal receiver, signal generators for correlated and uncorrelated signals, and a position estimator that uses cross-correlation signals to determine microphone positions without requiring specific test signals, allowing for continuous adaptation during audio playback.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If specific audio test signals are used for calibration, then position determination can be performed, but the system cannot adapt during normal operation and requires interruption of audio playback
Solution Approach 1:
The system continuously determines microphone positions during normal audio playback without interruption. The position estimation unit processes audio signals from multiple speakers in real-time, allowing continuous adaptation to changing acoustic environments while maintaining uninterrupted music rendering.
Solution Approach 2:
The system uses correlation signals as intermediaries to extract position information from normal audio content. By computing correlations between audio signals from different speakers and microphone inputs, the system can derive position data without requiring special test signals, thus enabling continuous operation during normal playback.
2Reliability
If normal audio signals are used for position determination, then continuous adaptation during playback is enabled, but position estimation reliability decreases due to unpredictable audio properties
Solution Approach 1:
The system segments the audio signal processing into distinct components: correlation signal generation from individual speaker channels, cross-correlation computation with microphone inputs, and position estimation from correlation peaks. This segmentation allows reliable position determination from complex normal audio by breaking it down into manageable processing stages.
Solution Approach 2:
The system performs preliminary correlation signal generation from speaker audio channels before comparing with microphone inputs. By pre-computing correlation signals and storing them, the system reduces the complexity of real-time position estimation, enabling reliable processing of normal audio signals through prepared reference data.
3Measurement precision
If multiple speakers are used for position determination, then accuracy is improved, but the system requires complex multi-channel signal processing
Solution Approach 1:
The system processes each speaker channel independently to generate separate correlation signals, then combines these through cross-correlation with microphone inputs. This segmentation approach maintains measurement precision by analyzing each speaker-microphone pair individually while managing complexity through systematic processing of multiple channels.
Solution Approach 2:
The system merges correlation information from multiple speaker channels to determine microphone position. By combining the correlation signals from different speakers through cross-correlation operations, the system achieves improved position accuracy through multi-channel information integration while maintaining manageable processing complexity.
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 enables improved and flexible microphone position determination with increased accuracy and reduced reliance on test signals, facilitating continuous system adaptation and improved audio rendering performance.
Implementation Method 1
a first correlator for determining a first correlation signal from a correlation of the microphone signal and the first correlated signal; a second correlator for determining a second correlation signal from a correlation of the microphone signal and the first uncorrelated signal
Data Source
AI summary
An apparatus comprises a receiver (203) receiving a multichannel signal comprising two channels for rendering by a first speaker (101) at a first position and a second speaker (103) at a second position respectively. A first signal generator (207) generates a correlated signal and a second signal generator (209) generates an uncorrelated signal from the multichannel signal, the signals comprising respectively correlated and uncorrelated signal components for the channels. A receiver (201) receives a microphone signal from the microphone (107). A first correlator (213) determines a first correlation signal from a correlation of the microphone signal and the correlated signal, and a second correlator (215) determines a second correlation signal from a correlation of the microphone signal and the uncorrelated signal. A position estimator (219) estimates a position of the microphone from the first and second correlation signals. For example, timings of peaks in the correlations signals may be used to determine propagation delays and thus distances from the speakers (101, 103).