Near-field sound source localization method under the condition of non-uniform array element noise based on ant colony optimization

Abstract

The invention relates to an ant colony optimization-based near field sound source localization method under a non-uniform array noise condition and belongs to the technical field of array signal processing. The method comprises the steps of firstly establishing a near field sound source signal model based on a plane array, further establishing the maximum likelihood estimation problem of direction and distance information of a sound source to be estimated under a space non-uniform noise condition, and finally estimating sound source parameters by using a continuous space ant colony optimization method, thus finishing the localization on the near field sound source under the space non-uniform noise condition. The method is higher in estimation precision, both direction and distance mean square errors of the sound source under low signal-to-noise are smaller than those of a conventional maximum likelihood method, and the direction and distance square mean errors of the sound source under the high signal-to-noise condition approach to a Cramer-Rao Boundary and are far superior than those of the normal maximum likelihood method.

Description

technical field [0001] The invention relates to a near-field sound source localization method under the condition of non-uniform array element noise based on ant colony optimization, which belongs to the field of array signal processing. Background technique [0002] Due to the important application value of sound source localization in radar, sonar, wireless communication, seismology and biomedicine, sound source localization based on sensor array has become one of the research hotspots in signal processing in recent years. However, traditional sound source localization is mostly based on far-field narrow-band assumptions, so only the azimuth information of the sound source can be estimated. When the sound source is relatively close to the array, that is, in the near field of the array, since the phase difference between different array elements is a function of the azimuth and distance of the sound source, it is necessary to extend the distance domain of the far-field narr...

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Problems solved by technology

[0003] However, the assumption of spatially uniform Gaussian noise does not fit some practical engineering problems

For example, due to the correlation noise between the elements of the compact radar array, the array output is a colored random process

As another example, for a microphone array with a large array element spacing, the output power of the array element noise is not the same due to mechanical vibration, array calibration errors, etc.

In both cases above, the performance of near-field source algorithms based on the assumption of spatially uniform Gaussian noise will be severely degraded

However, the conventional maximum likelihood method locates near-field sound sources under the condition of spatially non-uniform Gaussian noise. Since the determination of the sound source parameters requires multi-dimensional parameter space search and calculation, the complexity is extremely high and it is difficult to locate

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