37 init_ tdftaf

Purpose

Creates and initializes the variables required for the Transform Domain Fault Tolerant Adaptive Filter (TDFTAF). TDFTAF contains R redundant coefficients to guarantee that the filter will recover after the occurrence of a partial hardware failure during operation.

Syntax

[W,w,x,d,y,e,p] = init_tdftaf(L,R)
[W,w,x,d,y,e,p] = init_tdftaf(L,R,W0,x0,d0)

Description

The variables of the TDFTAF are summarized below (see Fig. 2.6 and Fig. 4.18).

Input Parameters [Size]::  

   L   : number of filter coefficients
   R   : number of redundant coefficients
   w0  : initial T-domain coef. vector [L+R x 1] 
   x0  : initial input samples vector [L x 1] 
   d0  : initial desired sample [1 x 1] 
Output parameters [default]::

   W   : initialized T-domain coef. vector [zeros]
   w   : initialized time-domain coef. vector [zeros]
   x   : initialized input vector [white noise]
   d   : initialized desired sample [white noise]
   y   : Initialized filter output
   e   : initialized error sample [e = d - y]
   p   : initialized power estimate

Example

L  = 5;           % Number of coefficients 
R  = 3;           % Redundant coefficients 
x0 = rand(5,1);   % initial delay line
d0 = 0;           % desired sample

% Create and initialize a TDFTAF FIR filter
[W,w,x,d,y,e,p]=init_tdftaf(L,R,[],x0,d0);

Remarks

• Supports both real and complex signals and filters.
• Use input parameters 3 through 5 to initialize the algorithm storage. This is helpful when the adaptation process is required to start from a known operation point calculated off-line or from previous simulations.

See Also

ASPTTDFTAF, ASPTTDLMS.