Convert reflection coefficients to prediction filter polynomial
a = rc2poly(k)
[a,efinal] = rc2poly(k,r0)
a = rc2poly(k) converts the reflection
coefficients k corresponding to the lattice structure to the
prediction filter polynomial a, with
a(1) = 1. The output
a is row vector of length
length(k) + 1.
[a,efinal] = rc2poly(k,r0) returns
the final prediction error efinal based on the zero-lag
autocorrelation, r0.
rc2poly computes output a using Levinson's
recursion [1]. The function
Sets the output vector a to the first
element of k.
Loops through the remaining elements of
k.
For each loop iteration i, a = [a +
a(i-1:-1:1)*k(i) k(i)].
Implements a = [1 a].
[1] Kay, Steven M. Modern Spectral Estimation. Englewood Cliffs, NJ: Prentice-Hall, 1988.