课程名称：    信息论与编码实验                             

实验名称：    线性分组码的编译码                             

一、实验内容

借助C++编程来实现对线性分组码的编码及其译码算法的实现

二、实验环境

   1、计算机

   2、VC++6.0

三、实验目的

  1、进一步熟悉线性分组码编译码的原理，及其基本的算法；

  2、通过编译，充分对于线性分组编译码有进一步的了解和掌握；

  3、掌握C++语言编程（尤其是数值的进制转换，数值与字符串之间的转换等）

四、实验要求

（1）实验前编写源程序、准备测试数据。

（2）在Turbo C下完成程序的编辑、编译、运行，获得程序结果。如果结果有误，应找出原因，并设法更正之。

五、实验总体思路

六、实验程序及分析

（7,4）码编译器整体程序：

#include

#include

void main()    

{

    /*G：生成矩阵  H：监督矩阵  HT：监督矩阵对应的转置矩阵*/

    /*M：输入信息序列  C：编码输出序列  Input：输入接收码序列  B：译码输出序列  S：伴随式*/

    int Q,N;/*定义开始*/

    int i,j,s,r,k,t,p,u,m;

    int G[4][7]={{1,0,0,0,1,1,1},{0,1,0,0,1,1,0},{0,0,1,0,1,0,1},{0,0,0,1,0,1,1}};

    int IR[3][3]={{1,0,0,},{0,1,0},{0,0,1}};

    int H[3][7], C[10][7],M[10][4],B[20][7],Input[100],HT[7][3],P[10],S[100][3];/*定义结束*/

    printf("\\n您好！欢迎使用线性分组码编译器！\\n");

    printf("\\n\\n本编译器针对（7，4）码，所采用的生成矩阵G=\\n");

for(i=0;i<4;i++)

    {

        for(j=0;j<7;j++)

            printf(" %d",G[i][j]);

        printf("\\n");

    }

    printf("编译码过程都是针对二进制码组，除了系统要求选择功能，其他情况下禁止输入除0，1以外的数。请在使用的过程中严格按照编译器要求的格式输入数据。\\n\\n");

    printf("现在请输入您所选择的编译器所对应的序号,按回车键继续:\\n");

    printf("\\n1.编码器  2.译码器  3.退出\\n");

    printf("\\n我选择：");

    scanf("%d",&Q);

    if(Q==0)

        Q+=4;

    while(Q)

    {

    if(Q==1||Q==2||Q==3)break;

    else

    {

        printf("对不起，您输入有误，请重新输入");

        scanf("%d",&Q);

    }

    }

    while(Q==1||Q==2||Q==3)

        {

            if(Q==1)/*编码程序*/

                {printf("\\n请输入您需要编码的信息组数");

                scanf("%d",&N);

                printf("\\n\\n请输入您需要编码的%d组四位二进制信息组,码组间用空格分开，按回车键确认。\\n",N);/*输入信息码*/

                printf("\\n信息组m=");

                for(i=0;i        scanf("%1d%1d%1d%1d",&M[i][3],&M[i][2],&M[i][1],&M[i][0]);/*求监督码*/

                for(i=0;i                {

                C[i][2]=M[i][3]^M[i][2]^M[i][1];

                C[i][1]=M[i][3]^M[i][2]^M[i][0];

                C[i][0]=M[i][3]^M[i][1]^M[i][0];

                }

                for(j=0;j                for (i=6;i>2;i--)/*输出编码结果*/

                    C[j][i]=M[j][i-3];

                printf("\\n您所输入的信息组编码结果c=");

                for(j=0;j                    for(i=6;i>=0;i--)

                    printf("%d",C[j][i]);

                printf("\\n\\n");

                printf("\\n接下来您想：\\n\\n");/*选择功能*/

                printf("1.用编码器 2.用译码器 3.退出\\n\\n");

                printf("我想：");

                scanf("%d",&Q);

            }

            else if(Q==2)/*译码程序*/

            {

                for(i=0;i<3;i++)/*求监督矩阵*/

                {

                    for(j=0;j<4;j++)

                        H[i][j]=G[j][i+4];

                    for(j=4;j<7;j++)

                        H[i][j]=IR[i][j-4];

                }

                printf("\\n监督矩阵H=\\n");/*输出监督矩阵*/

                for(i=0;i<3;i++)

                {

                    for(j=0;j<7;j++)

                        printf(" %d",H[i][j]);

                    printf("\\n");

                }

                t=1;

                while(t!=2)/*输入接收码组*/

                {

                    p=1;

                    printf("\\n请输入总位数为7的倍数的接收码组,每位用空格隔开，每组位数为7的倍数,以十进制2作为结束标志!按回车键确认\\n");

                    while(p)

                    {

                        for(i=0;;i++)

                        {

                            scanf("%d",&Input[i]);

                            if(Input[i]==2)break;

                        }

                        k=i%7;

                        if(k==0){p=0;t=2;}

                        else

                        {

                            p=1;

                            k=-k+7;

                            printf("您接收到的码组丢失了%d位,系统不能判断丢失位的具体位置，请重新输入\\n",k);

                        }

                    }

                }

                u=i/7;

                i=0;

                for(r=0;r                {    for(j=6;j>=0;j--,i++)

                        B[r][j]=Input[i];

                }

                printf("\\n将接收码组每七位分为一个码组，如下：\\n");

                    for(i=0;i                    {

                        for(j=0;j<7;j++)

                            printf(" %1d",B[i][6-j]);

                        printf("\\n");

                    }

                for(i=0;i<3;i++)/*求监督矩阵H的转置矩阵*/

                    for(j=0;j<7;j++)

                        HT[j][i]=H[i][j];

                    for(i=0;i                    {

                        for(m=0;m<3;m++)

                        {

                            for(j=0;j<7;j++)

                            {

                                s+=(B[i][6-j]*HT[j][m]);

                            }

                            if (s%2==1)s=1;

                            else 

                                s=0;

                            S[i][2-m]=s;

                            s=0;

                        }

                    }

                    printf("\\n\\n伴随式S=\\n");/*输出伴随式*/

                for(j=0;j                {for(i=2;i>=0;i--)

                    printf(" %1d",S[j][i]);

                printf("\\n");}

                printf("\\n");

                for(i=0;i                {

                P[i]=4*S[i][2]+2*S[i][1]+S[i][0]+1;

                switch(P[i])/*根据伴随式判断接收码，并译码*/

                {

                case 1:

                    {

                        printf("\\n\\n您所接收的第%d个码组正确，它是：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                        printf("请您再次确认！");

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 2:

                    {

                        B[i][0]=1^B[i][0];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                        printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 3:

                    {

                        B[i][1]=1^B[i][1];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 4:

                    {

                        B[i][3]=1^B[i][3];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 5:

                    {

                        B[i][2]=1^B[i][2];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 6:

                    {

                        B[i][4]=1^B[i][4];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 7:

                    {

                        B[i][5]=1^B[i][5];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                case 8:

                    {

                        B[i][6]=1^B[i][6];

                    printf("\\n\\n您接收的第%d个码组有错误，正确的码组应为：",++i);

                        i--;

                        for(j=6;j>=0;j--)

                            printf("%1d",B[i][j]);

                            printf("译出的信息序列为：");

                        for(j=6;j>2;j--)

                            printf("%d",B[i][j]);break;

                    }

                }

                }

                printf("\\n\\n总的译码结果为：");

                for(i=0;i                    for(j=6;j>2;j--)

                        printf("%1d",B[i][j]);

                printf("\\n\\n接下来您想：\\n\\n");/*继续选择功能*/

                printf("1.用编码器 2.用译码器 3.退出\\n\\n");

                printf("我想：");

                scanf("%d",&Q);

                if(Q==0)

                    Q=Q+4;

                while(Q)

                {

                    if(Q==1||Q==2||Q==3)break;

                    else

                    {

                        printf("对不起，您输入有误，请重新输入");

                        scanf("%d",&Q);

                    }

                }

            }

            else if(Q==3)/*退出程序*/

            {

                printf("\\n谢谢您的使用，欢迎再次使用！\\n");    Q=0;

            }

        }

}

运行的结果：

编码实验：B=A*G

译码实验： 

七、实验心得体会

通过本次实验，将课本上的理论知识与实际结合起来操作，我对线性分组码的原理及其编译码方法有了更为深入的理解。

    在实验过程中，我们经过对程序进行分析与调试后，我们在课本上找了个例子，对其编码器的编译码做了一步理论上的检验，运行的出来的结果与我们的计算结果是完全符合。