v34recv.c

数字通信第四版原书的例程

/*
 * V34trans   A SIMULINK example for v34 transmission
 *
 *  Syntax:  [sys, x0] = v34recv(t,x,u,flag,rate,ShMp)
 *
 * rate is a 12 element vector, which contains:
 * rate = [rate_s, rate_r,    rate_s_j, rate_s_p, rate_s_n, 
 *         rate_b, rate_q,    rate_K,   rate_M,   rate_M_exp,
 *         rate_L, rate_L_exp];
 * see V34param for the details of the rate parameter.
 *
 * ShMp is a four column matrix
 * ShMp(:, 1) contains g2
 * ShMp(:, 2) contains g4
 * ShMp(:, 3) contains g8
 * ShMp(:, 4) contains z8
 *
 * Wes Wang  Jan. 24, 1996
 * Copyright (c) 1996 by The MathWorks, Inc.
 * All Rights Reserved
 * $Revision: 1.1 $  $Date: 1996/04/01 19:07:37 $
 */
#define S_FUNCTION_NAME v34recv
 

#ifdef MATLAB_MEX_FILE
#include <stdio.h>    /* needed for declaration of sprintf */
#include "mex.h"      /* needed for declaration of mexErrMsgTxt */
#endif

#include "simstruc.h"

/* Defines for easy access of the input parameters */
#define NUM_ARGS   2
#define RATE       ssGetArg(S,0)
#define ShMp       ssGetArg(S,1)
                        
/*
 * mdlInitializeSizes - called to initialize the sizes array stored in
 *                      the SimStruct.  The sizes array defines the
 *                      characteristics (number of inputs, outputs,
 *                      states, etc.) of the S-Function.
 */

static void mdlInitializeSizes(S)
    SimStruct *S;
{
    int  rate_s = (int) mxGetPr(RATE)[0];
    int  rate_r = (int) mxGetPr(RATE)[1];
    int  rate_j = (int) mxGetPr(RATE)[2];
    int  rate_p = (int) mxGetPr(RATE)[3];
    int  rate_b = (int) mxGetPr(RATE)[5];
    int  rate_q = (int) mxGetPr(RATE)[6];
    int  rate_K = (int) mxGetPr(RATE)[7];
    int  rate_M = (int) mxGetPr(RATE)[8];

    /*
     * Set-up size information.
     */ 
/*    
#ifdef MATLAB_MEX_FILE
if (0) {
    char    err_msg[256];
    sprintf(err_msg, "Size initial, rate_s = %d; rate_r = %d; rate_j = %d; rate_p = %d;\n", rate_s, rate_r, rate_j, rate_p);
    mexPrintf(err_msg);
    sprintf(err_msg, "rate_b = %d; rate_q = %d; rate_K = %d; rate_M = %d;\n", rate_b, rate_q, rate_K, rate_M);
    mexPrintf(err_msg);
    sprintf(err_msg, "ShMp_N= %d, ShMp_M=%d;\n", mxGetN(ShMp), mxGetM(ShMp));
    mexPrintf(err_msg);    
}
#endif
*/
    if (ssGetNumArgs(S) == NUM_ARGS) {
      ssSetNumContStates(    S, 0);
      ssSetNumDiscStates(    S, 0);
      ssSetNumOutputs(        S, rate_b);
      ssSetNumInputs(       S, rate_q + 1 + 3 + 2);
      ssSetDirectFeedThrough(S, 1);
      ssSetNumInputArgs(     S, NUM_ARGS);
      ssSetNumSampleTimes(   S, 1);
      ssSetNumRWork(         S, 0);
      /* 1 last updata
       * 1 last trigger intput
       * 1 current input counter
       * 23 scramble
       * 8 mijk number
       * 4 * 3 of Iij
       * 8 * rate_q of Qijk
       */
      ssSetNumIWork(         S, 1 + 1 + 1 + 23 + 8 + 12 + 8*rate_q);
      ssSetNumPWork(         S, 0);
    } else {
#ifdef MATLAB_MEX_FILE
      char err_msg[256];
      sprintf(err_msg, "Wrong number of input arguments passed to S-function MEX-file.\n"
           "%d input arguments were passed in when expecting %d input arguments.\n", ssGetNumArgs(S) + 4, NUM_ARGS + 4);
      mexErrMsgTxt(err_msg);
#endif
    }
}

/*
 * mdlInitializeSampleTimes - initializes the array of sample times stored in
 *                            the SimStruct associated with this S-Function.
 */

static void mdlInitializeSampleTimes(S)
    SimStruct *S;
{
    /*
     * Note, blocks that are continuous in nature should have a single
     * sample time of 0.0.
     */

    ssSetSampleTimeEvent(S, 0, 0.0);
    ssSetOffsetTimeEvent(S, 0, 0.0);
}

/*
 * mdlInitializeConditions - initializes the states for the S-Function
 */

static void mdlInitializeConditions(x0, S)
    double *x0;
    SimStruct *S;
{
    int  rate_s = (int) mxGetPr(RATE)[0];
    int  rate_r = (int) mxGetPr(RATE)[1];
    int  rate_j = (int) mxGetPr(RATE)[2];
    int  rate_p = (int) mxGetPr(RATE)[3];
    int  rate_b = (int) mxGetPr(RATE)[5];
    int  rate_q = (int) mxGetPr(RATE)[6];
    int  rate_K = (int) mxGetPr(RATE)[7];
    int  rate_M = (int) mxGetPr(RATE)[8];
    
    int *last_updata = ssGetIWork(S);
    int *last_input = ssGetIWork(S) + 1;
    int *out_count   = ssGetIWork(S) + 2;
    int *scramble    = ssGetIWork(S) + 3;
    int *mijk        = ssGetIWork(S) + 3 + 23;
    int *Iij         = ssGetIWork(S) + 3 + 23 + 8;
    int *Qijk        = ssGetIWork(S) + 3 + 23 + 8 + 12;
    
    int i;
/*
#ifdef MATLAB_MEX_FILE
if (0) {
    char    err_msg[256];
    sprintf(err_msg, "Parame initial rate_s = %d; rate_r = %d; rate_j = %d; rate_p = %d;\n", rate_s, rate_r, rate_j, rate_p);
    mexPrintf(err_msg);
    sprintf(err_msg, "rate_b = %d; rate_q = %d; rate_K = %d; rate_M = %d;\n", rate_b, rate_q, rate_K, rate_M);
    mexPrintf(err_msg);
    sprintf(err_msg, "ShMp_N=%d , ShMp_M=%d;\n", mxGetN(ShMp), mxGetM(ShMp));
    mexPrintf(err_msg);    
}
#endif
*/
    *last_updata = 0;
    *last_input = 0;
    *out_count   = 0;
    
    for (i = 0; i < 23; i++)
        scramble[i] = 0;
    for (i = 0; i < 8; i++)
        mijk[i] = 0;
    for (i = 0; i < 12; i++)
        Iij[i] = 0;        
    for (i = 0; i < 8 * rate_q; i++)
        Qijk[i] = 0;
}

/*
 * mdlOutputs - computes the outputs of the S-Function
 */

static void mdlOutputs(y, x, u, S, tid)
    double *y, *x, *u;
    SimStruct *S;
    int tid;
{
    int  rate_s = (int) mxGetPr(RATE)[0];
    int  rate_r = (int) mxGetPr(RATE)[1];
    int  rate_j = (int) mxGetPr(RATE)[2];
    int  rate_p = (int) mxGetPr(RATE)[3];
    int  rate_b = (int) mxGetPr(RATE)[5];
    int  rate_q = (int) mxGetPr(RATE)[6];
    int  rate_K = (int) mxGetPr(RATE)[7];
    int  rate_M = (int) mxGetPr(RATE)[8];
    
    int *last_updata = ssGetIWork(S);
    int *last_input = ssGetIWork(S) + 1;
    int *out_count   = ssGetIWork(S) + 2;
    int *scramble    = ssGetIWork(S) + 3;
    int *mijk        = ssGetIWork(S) + 3 + 23;
    int *Iij         = ssGetIWork(S) + 3 + 23 + 8;
    int *Qijk        = ssGetIWork(S) + 3 + 23 + 8 + 12;

    /* input data */
    if ((u[rate_q + 5] > 0) && (*last_input == 0)) {
#ifdef MATLAB_MEX_FILE
        if (0) {
            char    err_msg[256];
            int i;
            sprintf(err_msg, "Input:");
            mexPrintf(err_msg);
            for (i = 0; i < rate_q + 6; i++) {            
                sprintf(err_msg, "u[%d] = %d; ", i, (int)u[i]);
                mexPrintf(err_msg);
            }
            sprintf(err_msg, "\n");
            mexPrintf(err_msg);            
        }        
#endif
        if (*out_count < 8) {
            long base_count, k, tmp, i;

            k = *out_count % 2;
            base_count = *out_count * rate_q;
            
            for (i = 0; i < rate_q; i++) {
                Qijk[base_count + i] = (int)u[i];
            }
            mijk[*out_count] = u[rate_q];
            if (k) {
                base_count = *out_count / 2;
                base_count = base_count * 3;
                for (i = 0; i < 3; i++) {
                    Iij[base_count + i] = (int)u[rate_q + 1 + i];
                }
            }
            /* at the very end */
            *out_count = *out_count + 1;
            *last_input = 1;
        }
    } else {
        if (u[rate_q + 5] <= 0)
           *last_input = 0;
    }

    /* updata the output */
    if ((u[rate_q + 4] > 0) && (*last_updata == 0)) {
        /* begin the major updating work. */
        double  *g2 = mxGetPr(ShMp);
        double  *g4 = mxGetPr(ShMp) + 8 *(rate_M-1)+1;
        double  *g8 = mxGetPr(ShMp) + 16*(rate_M-1)+2;
        double  *z8 = mxGetPr(ShMp) + 24*(rate_M-1)+3;

        long R[6];
        long A, B, C, D, E, F, G, H, tmp;
        int  i, j, k, data_in[80]; /*b is no larger than 40 */

        /* Shell Demapper */
        C = mijk[0] + mijk[1];
        if (C < rate_M) {
            E = mijk[0];
        } else {
            E = rate_M - 1 - mijk[1];
        }
        B = C + mijk[2] + mijk[3];
        if (B - C < rate_M) {
            F = mijk[2];
        } else {
            F = rate_M - 1 - mijk[3];
        }
        D = mijk[4] + mijk[5];
        if (D < rate_M) {
            G = mijk[4];
        } else {
            G = rate_M - 1 - mijk[5];
        }
        A = B + D + mijk[6] + mijk[7];
        if (A - B - D < rate_M) {
            H = mijk[6];
        } else {
            H = rate_M - 1 - mijk[7];
        }

        /* determine R[0 - 5] */

        R[5] = H * g2[D] + G;
        R[4] = F * g2[C] + E;
        R[3] = R[5];
        if (D > 0) {
            for (i = 0; i < D; i++) {
                R[3] = R[3] + g2[i] * g2[A - B - i];
            }
        }
        R[2] = R[4];
        if (C > 0) {
            for (i = 0; i < C; i++) {
                R[2] = R[2] + g2[i] * g2[B - i];
            }
        }
        R[1] = R[3] * g4[B] + R[2];
        R[0] = R[1] + z8[A];
        if (B > 0) {
            for (i = 0; i < B; i++) {
                R[0] = R[0] + g4[i] * g4[A - i];
            }
        }
#ifdef MATLAB_MEX_FILE
if (0) {
    char    err_msg[256];
    sprintf(err_msg, "Answer\n");
    mexPrintf(err_msg);    
    sprintf(err_msg, "A = %d; B = %d; C = %d; D = %d; E = %d; F = %d; G = %d; H = %d \n",A, B, C, D, E, F, G, H );
    mexPrintf(err_msg);
    sprintf(err_msg, "R[0]=%d; R[1]=%d; R[2]=%d; R[3]=%d; R[4]=%d; R[5]=%d \n",R[0],R[1],R[2],R[3],R[4],R[5]);
    mexPrintf(err_msg);
    sprintf(err_msg, "mijk[0]=%d; mijk[1]=%d; mijk[2]=%d; mijk[3]=%d; mijk[4]=%d; mijk[5]=%d; mijk[6]=%d; mijk[7]=%d \n",mijk[0],mijk[1],mijk[2],mijk[3],mijk[4],mijk[5],mijk[6],mijk[7]);
    mexPrintf(err_msg);        
}
#endif
        A = R[0];

		/*parser */
        /* data_in[0:K-1] Si1 -- SiK                  -- Si?
         * data_in[K:K+2] I1i0, I2i0, I3i0            -- I?ij
         * data_in[K+3:K+3+q-1] Qi001, ..., Qi00q     -- Qijk?
         * data_in[K+3+q:K+3+2*q-1] Qi011, ..., Qi01q -- Qijk?
         * data_in[K+3+2*q:K+3+2*q+2] I1i1, I2i1, I3i1
         * data_in[K+6+2*q:K+6+3*q-1] Qi101, ..., Qi10q
         * data_in[K+6+3*q:K+6+4*q-1] Qi111, ..., Qi11q
         * data_in[K+6+4*q:K+6+4*q+2] I1i2, I2i2, I3i2         
         * data_in[K+9+4*q:K+9+5*q-1] Qi201, ..., Qi20q
         * data_in[K+9+5*q:K+9+6*q-1] Qi211, ..., Qi21q
         * data_in[K+9+6*q:K+9+6*q+2] I1i3, I2i3, I3i3
         * data_in[K+12+6*q:K+12+7*q-1] Qi301, ..., Qi30q
         * data_in[K+12+7*q:K+12+8*q-1] Qi311, ..., Qi31q
         */

        /* calculate S1 to Sk */
        for (i = 0; i < rate_K; i++) {
            data_in[i] = A % 2;
            A /= 2;
        }

        /* arrange the rest of the data */
        i = rate_K;
        j = 0;
        k = 0;
        for (A = 0; A < 4; A++) {
            for (B = 0; B < 3; B++) {
                data_in[i] = Iij[j];
                j++;
                i++;
            }
            for (C = 0; C < 2*rate_q; C++) {
                data_in[i] = Qijk[k];
                k++;
                i++;
            }
        }
        if (1) {
            /* descramble */
            for (i = 0; i < rate_b; i++) {
                y[i] = (double)((data_in[i] + scramble[17] + scramble[22]) % 2);
                for (j = 22; j > 0; j--)
                    scramble[j] = scramble[j-1];
                scramble[0] = data_in[i];
            }
        } else {
            for (i = 0; i < rate_b; i++)	    
                y[i] = data_in[i];
        }
        *out_count = 0;
        *last_updata = 1;        
    } else if (u[rate_q+4] <= 0) {
        *last_updata = 0;
    } else if (ssGetT(S) <= 0) {
        int i;
        for (i = 0; i < rate_b; i++)
            y[i] = 0;
    }

}

/*
 * mdlUpdate - computes the discrete states of the S-Function
 */

static void mdlUpdate(x, u, S, tid)
    double *x, *u;
    SimStruct *S;
    int tid;
{
}

/*
 * mdlDerivatives - computes the derivatives of the S-Function
 */

static void mdlDerivatives(dx, x, u, S, tid)
    double *dx, *x, *u;
    SimStruct *S;
    int tid;
{
}

/*
 * mdlTerminate - called at termination of model execution.
 */

static void mdlTerminate(S)
    SimStruct *S;
{
}

#ifdef  MATLAB_MEX_FILE    /* Is this file being compiled as a MEX-file? */
#include "simulink.c"      /* MEX-File interface mechanism */
#else
#include "cg_sfun.h"       /* Code generation registration function */
#endif