Research Article

A Generalization Belief Propagation Decoding Algorithm for Polar Codes Based on Particle Swarm Optimization

Algorithm 1

BP decoding algorithm based on modified PSO optimization.
Input:
   The stopping parameters and ;
   The frozen nodes set, ;
   The probability messages of the input nodes of the decoder, ;
Output:
   The decoded source binary vector, ;
(1)   Initialize the parameters used in the PSO algorithm, including particles initial set ,
    the pseudovelocities , particle inertia , maximum iteration number and , ;
(2)  while (Stopping criterion is not satisfied) do
(3)     Update particle pseudovelocity vector using (17);
(4)    Update particle position vector using (16);
(5)    Calculate the probability messages of each nodes in the decoder using (11);
(6)    if   and   then
(7)     Calculate the fitness value using (19);
(8)     if     then
(9)       , ;
(10)    end if
(11)     if     then
(12)      , ;
(13)     end if
(14)    end if
(15) end while
(16) Output the decoded source binary vector by hard decision of the output nodes of the decoder;
(17) return   ;