viterbi软判决硬判决译码算法

viterbi软判决和硬判决译码算法， 两个函数，有详细注释

%硬判决
function decoder_output=viterbi_hard（yL） 
global G;
n=size（G1）; 
K=size（G2）; 
number_of_states=2^（K-1）; 
%------------------------------------------------
%-------------生成各分支的输出--------------------
%------------------------------------------------
for j=0:number_of_states-1 
    for t=0:1 
        [next_statememory_contents]=next_state_fun（jtK）; 
        input（j+1next_state+1）=t; 
        branch_output=rem（memory_contents*G‘2）; 
        nextstate（j+1t+1）=next_state; 
        output（j+1t+1）=bin2deci（branch_output）; 
    end 
end 
%------------------------------------------------
metric_of_states=zeros（1number_of_states）;                 %各状态的度量metric
metric_of_states_c=zeros（number_of_states2）;               %各状态两个输入的度量
length_seq=length（y）/n;                               %符号个数
decoder_output=zeros（1length_seq-K+1）;                     %解码输出
channel_output_matrix=reshape（ynlength_seq）;        %将解调输出的比特按符号排列 
survivor_state=zeros（number_of_stateslength_seq+1）;        %留存路径 
input_of_state=zeros（number_of_stateslength_seq+12）;      %汇聚到各状态的分支对应的输入
state_sequence=zeros（1length_seq+1）;                       
count=zeros（1number_of_states）;
for i=1:length_seq-K+1 
%------------------------------------------------
    for j=0:number_of_states-1 
        for t=0:1
            binary_output=deci2bin（output（j+1t+1）n）;      %将各分支的输出转换为2进制
            branch_metric=Hamming_dis（channel_output_matrix（:i）‘binary_output）;       %计算分支度量
            count（nextstate（j+1t+1）+1）=count（nextstate（j+1t+1）+1）+1;                  
            metric_of_states_c（nextstate（j+1t+1）+1count（nextstate（j+1t+1）+1））=metric_of_states（j+1）+branch_metric;   %计算累积度量（加）
            input_of_state（nextstate（j+1t+1）+1:count（nextstate（j+1t+1）+1））=survivor_state（j+1:）;                   %该分支所在路径的对应的输入
            input_of_state（nextstate（j+1t+1）+1icount（nextstate（j+1t+1）+1））=t;                                       
        end;
    end;
%----------------比较汇聚到同一状态的两条路径，选取距离较小的-----------------    
    for j=0:number_of_states-1
        if metric_of_states_c（j+11）>=metric_of_states_c（j+12）
            metric_of_states（j+1）=metric_of_states_c（j+12）;
            survivor_state（j+1:）=input_of_state（j+1:2）;
        else
           metric_of_states（j+1）=metric_of_states_c（j+11）; 
           survivor_state（j+1:）=input_of_state（j+1:1）;
        end;
    end;
    count=zeros（1number_of_states）;
 %--------------------------截短输出------------------------------------
    if i>L
        [min_metriclocation]=min（metric_of_states）;
        decoder_output（i-L）=survivor_state（locationi-L）;
    end;  
end  
 %---------------------最后L个比特译码输出--------------------------------
[min_metriclocation]=min（metric_of_states）;
decoder_output（length_seq-K+1-L+1:length_seq-K+1）=survivor_state（locationlength_seq-K+1-L+1:length_seq-K+1）;
% =========================================================

 属性            大小     日期    时间   名称
----------- ---------  ---------- -----  ----
     文件        3130  2017-12-04 11:53  viterbi_hard.m
     文件        2688  2018-01-02 15:59  viterbi_soft.m