Method for obtaining a position of a sound source
AssigneeNomono AS
InventorAudun Solvang
Life of this patent
Estimating the term…
Abstract
The invention relates to a method for obtaining a position of a sound source relative to a dedicated reference point. A first and a plurality of second sound signals are recorded which are synchronized in time. The position can be obtained by applying an estimated filter to a correlated signal derived by correlation of the first sound signal with at least one of the plurality of second sound signals in the frequency domain. Two timing values are derived in the at least one filtered and correlated signal exceeding a dedicated threshold in the time domain. Then the distance between the dedicated reference point and the sound source based on the respective obtained first timing value and second timing value.
Claims20
A method for obtaining a position of a sound source relative to a dedicated reference point, comprising the steps of:
- obtaining a first sound signal recorded at a sound source;
- obtaining a plurality of second sound signals each recorded at a position in a known relation to the dedicated reference point;
- wherein the first sound signal and the plurality of second sound signals are synchronized in time;
- for the first sound signal:
- estimating a filter acting on the signal-to-noise ratio in each frequency bin of the first sound signal in a time-frequency domain;
- correlating the first sound signal with at least one of the plurality of second sound signals in the frequency domain to obtain at least one correlated signal;
- applying said filter to the at least one correlated signal to obtain at least one filtered and correlated signal;
- obtaining a first timing value in the at least one filtered and correlated signal exceeding a dedicated threshold in the time domain;
- and
- obtaining a second timing value corresponding to a threshold value in the at least one filtered and correlated signals based on the first timing value;
- and
- estimating the distance between the dedicated reference point and the sound source based on the respective obtained first timing value and second timing value.
A method for obtaining an angle of a sound source relative to a dedicated reference point, comprising the steps of:
- obtaining a first sound signal recorded at one or more sound sources;
- obtaining a plurality of second sound signals each recorded at a position in a known relation to the dedicated reference point;
- wherein the first sound signal and the plurality of second sound signals are synchronized in time;
- for the first sound signal:
- estimating a filter acting on the signal-to-noise ratio in each frequency bin of one of the first sound signal in a time-frequency domain;
- correlating the first sound signal with at least two of the plurality of second sound signals in the frequency domain to obtain at least two correlated signals;
- applying said filter to the correlated signal to obtain at least two filtered and correlated signals;
- truncating the at least two filtered and correlated sound signals around a specific time period selected such to cut-off reflection from the environment by at least the first sound signal;
- and
- obtaining a cross correlation between pairs of truncated filtered and correlated sound signals of the plurality of second sound signals;
- and
- obtaining the angle of arrival of the filtered first sound signal by projecting the obtained cross correlation in a spherical spatial space.
A computer system comprising:
- one or more processors;
- a memory coupled to the one or more processors and comprising instructions, which when executed by the one or more processors cause the one or more processors to perform the steps of:
- obtaining a first sound signal recorded at one or more sound sources;
- obtaining a plurality of second sound signals each recorded at a position in a known relation to a dedicated reference point;
- wherein the first sound signal and the plurality of second sound signals are synchronized in time;
- for the first sound signal:
- estimating a filter acting on the signal-to-noise ratio in each frequency bin of one of the first sound signal in a time-frequency domain;
- correlating the first sound signal with at least two of the plurality of second sound signals in the frequency domain to obtain at least two correlated signals;
- applying said filter to the correlated signal to obtain at least two filtered and correlated signals;
- truncating the at least two filtered and correlated sound signals around a specific time period selected such to cut-off reflection from the environment by at least the first sound signal;
- and
- obtaining a cross correlation between pairs of truncated filtered and correlated sound signals of the plurality of second sound signals;
- and
- obtaining the angle of arrival of the filtered first sound signal by projecting the obtained cross correlation in a spherical spatial space.
Dependencies are inferred from the claim text.