% perform one iteration of joint data and channel estimation for the x4 example
% using alternating LLSQ solutions for A and h
%
% This method does not use the Viterbi algorithm.

% get estimated data values
%
  H = get_H( FIR, N);

  b = H\(z');

  bd = 2*(b > 0) - 1;	% discretized values

% check accuracy
%
  sum( bd' ~= x)

% set LLSQ coefficient matrix
%
% use b or discretized bd?
%
  A = get_A( b, N, Memory);

% solve for the new channel coefficients
%
  FIR = A\(z')
