Research Article

An Algorithm for Optimally Fitting a Wiener Model

Algorithm 2

Levenberg-Marquardt algorithm used.
Set 𝛼 .
Let 𝜈 = 2
For   𝑖 = 1 to 5  do
 Calculate the Jacobian 𝐽 .
 if   𝑖 = 1   then
   πœ† = m a x ( 𝐽 β€² 𝐽 ) β‹… 𝛼
 else
   1 πœ† = πœ† β‹… m a x ( 3 , 1 βˆ’ ( 2 πœ‚ βˆ’ 1 ) 3 )
 end if
  𝐺 = 𝐽 β€² 𝐟
  β„Ž = ( 𝐽 β€² 𝐽 + πœ† 𝐼 ) βˆ’ 1 𝐺
  Μ‚ Μ‚ πœƒ = πœƒ + β„Ž
  Μ‚ Μ‚ πœ‚ = 𝐹 ( πœƒ βˆ’ β„Ž ) βˆ’ 𝐹 ( πœƒ ) β„Ž β€² ( πœ† β„Ž βˆ’ 𝐺 )
 if   πœ‚ > 0   then
   𝜈 = 2
 else
   πœ† = πœ† β‹… 𝜈
   𝜈 = 2 𝜈
  if   𝜈 > 1 2 8   then
   break
  end if
 end if
end for