24 init_ bnlms

Purpose

Creates and initializes the variables required for the Block Normalized Least Mean Squares adaptive filter.

Syntax

[w,x,d,e,y,p] = init_bnlms(N,L)
[w,x,d,e,y,p] = init_bnlms(N,L,w0,x0,d0)

Description

The variables of the BNLMS are summarized below (see Fig. 2.6).

Input Parameters [Size]:: 
  N  : filter length
  L  : new samples per block (block length)
  w0 : initial filter coefficients vector [N x 1]
  x0 : initial input delay line [N x 1]
  d0 : initial desired response vector [L x 1]

Output parameters [default]::
  w  : initialized filter coefficients vector [zeros]
  x  : initialized input delay line [zeros]
  d  : initialized desired response vector [white noise]
  e  : initialized error vector 
  y  : initialized filter output vector
  p  : initialized estimate of the power of x

Example

N  = 5;           % Block length
L  = 5;           % Number of coefficients 
w0 = [0;0;1;0;0]; % initial filter coefficients 
x0 = rand(N,1);   % initial delay line
d0 = x0;          % desired sample

% Create and initialize a BNLMS FIR filter
[w,x,d,e,y,p]=init_bnlms(N,L,w0,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

ASPTBNLMS.