本文格式為Word版，下載可任意編輯——卷積碼(312)編譯碼程序電子信息與計(jì)算機(jī)工程系2023級(jí)信息工程

——卷積碼（312）

1.卷積碼編譯碼程序1.1內(nèi)嵌函數(shù)trel1.m

clear;clc

trel=poly2trellis(3,[06,05,07]);

msg=randint(1,10)code=convenc(msg,trel)code1=encode312(msg)code-code1

msg1=decode_312(code)msg-msg1

1.2編碼程序encode312.m

functioncode=encode312(msg)code=zeros(1,length(msg)*3);current=[00];fori=1:length(msg)

[out,next]=state_machine(msg(i),current);current=next;code(3*i-2)=out(1);code(3*i-1)=out(2);code(3*i)=out(3);end

2023級(jí)信息工程

1.3狀態(tài)積state_machine.m

function[output,nextState]=stat_machine(input,current_state)output(1)=mod(input+current_state(1),2);output(2)=mod(input+current_state(2),2);

output(3)=mod(input+current_state(1)+current_state(2),2);nextState(1)=input;

nextState(2)=current_state(1);

1.4漢明距離hamming.m

functiondistance=hamming(a,b)temp=a+b;

temp=mod(temp,2);distance=sum(temp);

1.5譯碼程序decode_312.m

functionmsg=decode_312(code)chip=6;

fori=1:2^chip

M(i,:)=de2bi(i-1,chip);W(i,:)=encode312(M(i,:));

D(i)=hamming(W(i,:),code(1:chip*3));end

[val,index]=sort(D);

ret_msg=zeros(1,length(code)/3);fori=1:4

ret_msg(i,1:chip)=M(index(i),:);ret_dis(i)=D(index(i));end

iter=(length(code)-chip*3)/3;fori=1:iterforj=1:4

msg_temp1=[ret_msg(j,1:chip+i-1)0];msg_temp2=[ret_msg(j,1:chip+i-1)1];code_temp1=encode312(msg_temp1);code_temp2=encode312(msg_temp2);

dis_temp1=hamming(code_temp1,code(1:chip*3+3*i));

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