Near field sound source real-time positioning system based on microphone array

Abstract

The invention discloses a near field sound source real-time positioning system based on a microphone array, belonging to the technical field of sound source positioning. The positioning system comprises a microphone array, an amplifying circuit module, a signal acquiring and processing module, a positioning result storage module and other system assistance modules. Voice signals are amplified through the microphone array, and the amplifying circuit adopts a special microphone amplifier with an automatic gain function as a core. The signal acquiring and processing module takes a DSP chip with an on-chip analog-to-digital conversion function as a core, and adopts the direct storage access function in the DSP chip. A near-field two-dimensional broadband MUSIC algorithm is further optimized, the acceptation or rejection of the microphone array signal frequency spectrum sub-band is carried out, a sub-band matrix is subjected to MUSIC spectrum estimation, the computation burden of DSP chip is reduced, and the system instantaneity is improved. The sound source positioning result storage module adopts an SD card as a storage medium, the application range of the system is improved, and thecluster chain of speaker position data is constructed by adopting a 'pre-built cluster chain method', so that the system instantaneity is improved.

Description

technical field

[0001] The invention belongs to the technical field of sound source localization, and in particular relates to a near-field sound source real-time localization system based on a microphone array. Background technique

[0002] As a common acoustic-electric transducer for collecting sound signals, especially voice signals, microphones are widely used in multimedia conferencing, teaching, communication, vibration and noise detection of mechanical equipment, military command and reconnaissance, etc.

[39] . At present, audio collection related products on the market mainly use a single microphone as the audio signal collection unit, and some high-end products use various forms of microphone arrays as sensors for audio signal collection and processing. In traditional conferences, a single microphone is usually used to collect the voice information of the speaker, and the content of the conference recording is sorted out and proofread manually after the conference. H...

Examples

specific Embodiment 1

[0044] In the microphone array and its amplifying circuit, the electret microphone adopts the NMI9745 electret microphone, and the amplifier adopts the MAX9814L microphone special amplifier, according to image 3 Schematic connections of a single electret microphone and its amplifying circuit shown in .

[0045] When the AGC module inside the MAX9814L detects that the output voltage exceeds a preset threshold, it will reduce the gain according to an optional time coefficient. This time constant is called "Attack Time". When the signal output amplitude decreases, the gain will remain in a reduced state for a short time, this time is called "Hold Time". followed by a slow increase to the normal value, this time is called

[0046] "Release Time". The time factor for reducing the gain t attack It can be obtained by the following formula.

[0047] t attack =2400×C CT

[0048] Attack Time (t attack ) and Release Time (t release ) ratio t attack / t release , A / R pin state ...

technical field

[0001] The invention belongs to the technical field of sound source localization, and in particular relates to a near-field sound source real-time localization system based on a microphone array. Background technique

[0002] As a common acoustic-electric transducer for collecting sound signals, especially voice signals, microphones are widely used in multimedia conferencing, teaching, communication, vibration and noise detection of mechanical equipment, military command and reconnaissance, etc.

[39] . At present, audio collection related products on the market mainly use a single microphone as the audio signal collection unit, and some high-end products use various forms of microphone arrays as sensors for audio signal collection and processing. In traditional conferences, a single microphone is usually used to collect the voice information of the speaker, and the content of the conference recording is sorted out and proofread manually after the conference. H...

Examples

specific Embodiment 1

[0044] In the microphone array and its amplifying circuit, the electret microphone adopts the NMI9745 electret microphone, and the amplifier adopts the MAX9814L microphone special amplifier, according to image 3 Schematic connections of a single electret microphone and its amplifying circuit shown in .

[0045] When the AGC module inside the MAX9814L detects that the output voltage exceeds a preset threshold, it will reduce the gain according to an optional time coefficient. This time constant is called "Attack Time". When the signal output amplitude decreases, the gain will remain in a reduced state for a short time, this time is called "Hold Time". followed by a slow increase to the normal value, this time is called

[0046] "Release Time". The time factor for reducing the gain t attack It can be obtained by the following formula.

[0047] t attack =2400×C CT

[0048] Attack Time (t attack ) and Release Time (t release ) ratio t attack / t release , A / R pin state ...

Images