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Estimate LPC's

Started by rahulparthasarthy May 17, 2004
Hello,

I am trying to compute a solution using the least- square- error
principle to an overdetermined system of equations.

The equation is as below:

Error = summation (y[n] summation (ai x[n-i] ) ).... in 'ai '
term `i' is subscript

where `n' ranges from 1 to 300 and `i' ranges from 1 to 18. The
outside summation is for `n' (1,2,3,4,299,300) whereas the inside
summation is for 'i' (1,2,3,418)

I am interested in calculating `ai ` ( i is subscript) where 'ai'
represents Linear Prediction Coefficients. I could have used the
Levinson-Durbin algorithm but in this case, two different signals are
in consideration, namely, y[n] and x[n], and hence
the `autocorrelation' method cannot be used. I have y[n] and x[n]
available but not able to evaluate that expression.

I would be obliged if anybody could help me in solving/evaluating
the above equation so that I can find ai's (LP coefficients). Is it
possible to solve it using Maple, Matlab, Mathematica etc. or to
convert it to Ax=B matrix form. I am interseted in writing a C
program for the above expression to calculate LPC's.

Regards,
Rahul Parthasarthy




hi

in matlab there is a function already called LPC. You can use it or you can also use levinson algorithm to implement such things in matlab. You can also convert it into C command by using mcc- command, for more information look those commands in matlab.

best regards.

ulas bagci

ee eng.

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>
>Hello,
>
>I am trying to compute a solution using the least- square- error
>principle to an overdetermined system of equations.
>
>The equation is as below:
>
>Error = summation (y[n] summation (ai  x[n-i] ) ).... in  'ai '
>term `i' is subscript
>
>where `n' ranges from 1 to 300 and  `i' ranges from 1 to 18. The
>outside summation is for `n' (1,2,3,4,299,300)  whereas the inside
>summation is for 'i' (1,2,3,418)
>
>I am interested in calculating `ai ` ( i  is subscript) where 'ai'
>represents Linear Prediction Coefficients.  I could have used the
>Levinson-Durbin algorithm but in this case, two different signals are
>in consideration, namely, y[n] and x[n], and hence
>the `autocorrelation' method cannot be used. I have y[n] and x[n]
>available but not able to evaluate that expression.
>
>I would be obliged if anybody could help me in solving/evaluating
>the above equation so that I can find ai's (LP coefficients). Is it
>possible to solve it using Maple, Matlab, Mathematica etc. or to
>convert it to Ax=B matrix form. I am interseted in writing a C
>program for the above expression to calculate LPC's.
>
>Regards,
>Rahul Parthasarthy
>
>
>


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