US 7,496,482 B2 · Signal separation method, signal separation device and recording medium

Abstract

A method and a device for signal separation. First, values of signals observed by M sensors are transformed into frequency domain values, and these frequency domain values are used to calculate relative values of the observed values between the sensors at each frequency. These relative values are clustered into N clusters, and the representative value of each cluster is calculated. Then, using these representative values, a mask is produced to extract the values of the signals emitted by V (1≦V≦M) signal sources from the frequency-domain signal values, and this mask is applied to the frequency-domain signal values. After that, if V=1 then the limited signal is output directly as a separated signal, while if V≧2 then the separated values are obtained by separating this limited signal with separation techniques such as ICA.

Claims30

Dependent claims

A signal separation method that separates and extracts signals under conditions where N (N≧2) signals are mixed together and observed with M sensors, comprising:

a procedure that transforms the observed signal values observed by said sensors into frequency-domain signal values,
a procedure that uses said frequency-domain signal values to calculate at each frequency the relative values of the observed values between said sensors (including mapping these relative values),
a procedure that clusters said relative values into N clusters,
a procedure that calculates a representative value for each of said clusters,
a procedure that uses said representative values to generate a mask for the purpose of extracting, from said frequency-domain signal values, mixed signal values comprising the signals emitted from V (2≦V≦M) signal sources,
a procedure that uses said mask to extract said mixed signal values from said frequency-domain signal values, and
a procedure that separates and extracts the values of V signals from said mixed signal values.

4 more elements

A signal separation method that separates and extracts signals under conditions where N (N≧2) signals are mixed together and observed with M sensors, comprising:

a procedure that transforms the observed signal values x1(t), . . . , xM(t) observed by said sensors into frequency-domain signal values X1(f,m), . . . , XM(f,m),
a procedure that clusters first vectors X(f,m)=[X1(f,m), . . . , XM(f,m)] comprising said frequency-domain signal values X1(f,m), . . . , XM(f,m) into N clusters Ci(f) (i1, . . . , N) at each frequency f,
a procedure that calculates second vectors ai(f) to represent each said cluster Ci(f),
a procedure that extracts V (1≦V≦M) third vectors ap(f) (p=1, . . . , V) from said second vectors ai(f),
a procedure that generates a mask M(f,m) represented by the formula
M
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=
{
1
max
a
p
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(
f
)
∈
G
k
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D
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X
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)
,
a
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<
min
a
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0
otherwise
where Gk is the set of said third vectors ap(f), Gkc is the complementary set of Gk, and D(α,β) is the Mahanalobis square distance between the vectors α and β,
and a procedure that extracts the signal values emitted from V of said signal sources by calculating the product of said mask M(f,m) and said first vectors X(f,m).

76 more elements

A signal separation method that separates and extracts signals under conditions where N (N≧2) signals are mixed together and observed with M sensors, wherein

a procedure that transforms the observed signal values x1(t), . . . , xM(t) observed by said sensors into frequency-domain signal values X1(f,m), . . . , XM(f,m),
a procedure that clusters first vectors X(f,m)=[X1(f,m), . . . , XM(f,m)] comprising said frequency-domain signal values X1(f,m), . . . , XM(f,m) into N clusters Ci(f) (i=1, . . . , N) at each frequency f,
a procedure that calculates second vectors ai(f) to represent each said cluster C1(f),
a procedure that extracts V (1≦V≦M) third vectors ap(f) (p=1, . . . , V) from said second vectors ai(f),
and a procedure that judges whether or not said first vectors X(f,m) satisfy the relationship
maxap(f)∈GkD(X(f,m)ap(f))<minaq(f)∈GkcD(X(f,m),aq(f)) Formula 56
where Gk is the set of said third vectors ap(f), Gkc is the complementary set of Gk, and D(α, β) is the Mahanalobis square distance between the vectors αand β, and, if so, extracts said first vectors X(f,m) as the signal values emitted from V of the said signal sources.

4 more elements

A signal separation method that separates and extracts signals under conditions where N (N≧2) signals are mixed together and observed with M sensors, comprising

a procedure that transforms the observed signal values x1(t), . . . , xM(t) observed by said sensors into frequency-domain signal values X1(f,m), . . . , XM(F,m),
a procedure that clusters first vectors X(f,m)=[X1(f,m), . . . , XM(f,m)]T comprising said frequency-domain signal values X1(f,m), . . . , XM(gm) into N clusters Ci(f) (i=1, . . . , N) at each frequency f,
a procedure that calculates second vectors ai(f) to represent each said cluster Ci(f),
a procedure that calculates an N-row×M-column separation matrix W(f,m) that is the Moore-Penrose pseudo-inverse matrix of an M-row×N-column matrix in which 0 or more of the N said second vectors ai(f) are substituted with zero vectors,
and a procedure that calculates a separated signal vector Y(f,m)=[Y1(f,m), . . . , YN(f,m)]T by performing the calculation Y(f,m)=W(f,m)X(f,m).

2 more elements

Dependencies are inferred from the claim text.

Signal separation method, signal separation device and recording medium

Life of this patent

Signal separation method, signal separation device and recording medium

Life of this patent

Abstract

Claims30