s_channel_estimator.c

这是一个c＋＋编写的WCDMA链路采用RAKE接收的方针源代码

/*
 | Project:     WCDMA simulation environment
 | Module:     
 |              This function is a simulink interface to channel 
 |              estimation function. Currently this only checks 
 |              what channel (amplitude) taps are above
 |              given threshold and return those
 |              taps and the number of relevant taps   
 |
 | 
 | Author:      Maarit Melvasalo
 | Date:        May 1999
 |
 | History:
 |              May 18,  1999 Maarit Melvasalo 
 |      
 |
 |  Abstract:
 |
 | USER GIVEN PARAMETERS
 |
 | 1: THERS = threshold value for channel estimation
 | 2: nSlot = number od slot in a frame (used for sample timing)
 | 
 | Inputs:
 |        Channel 
 |        Delay
 |               
 | Outputs: 
 |        Channel
 |        Delay 
 |        Number of relevant channel taps 
 |
 | DEPENDS ON FILES 
 |         
 |
 | Copyright disclaimer:
 |   This software was developed at the National Institute of Standards
 |   and Technology by employees of the Federal Government in the course
 |   of their official duties. Pursuant to title 17 Section 105 of the
 |   United States Code this software is not subject to copyright
 |   protection and is in the public domain.
 |
 |   We would appreciate acknowledgement if the software is used.
 |

 */ 

#define S_FUNCTION_NAME s_channel_estimator
#define S_FUNCTION_LEVEL 2

#include <math.h>
#include "simstruc.h"
#include "channel.h"
#include "tmwtypes.h"
#include "config_wcdma.h"
#include "wcdma_simulink.h"


/* USER GIVEN PARAMETERS AND DEFINITIONS /**/


#define NPARAMS 2                               /* number of parameters /**/

#define THRES(S) ssGetSFcnParam(S,0)            /* Channel threshold*/
#define SLOTS(S)  ssGetSFcnParam(S,1)
#define nSlots (int_T)(mxGetPr(SLOTS(S))[0]) 


#define A(element) (*aPtrs[element])  /* Pointer to Input Port0 */
#define D(element) (*dPtrs[element])  /* Pointer to Input Port0 */

        /*turha, mutta ei se mitaan */

#define td  TD_FRAME / (real_T)nSlots  /*SLOT     /**/


/*====================*
 */
static void mdlInitializeSizes(SimStruct *S)
{
  ssSetNumSFcnParams(S, NPARAMS);  /* Number of expected parameters */

  if (ssGetNumSFcnParams(S) != ssGetSFcnParamsCount(S)) 
 {
      return;
 }
    ssSetNumContStates(S, 0);
    ssSetNumDiscStates(S, 0);

    if (!ssSetNumInputPorts(S, 2)) return;
    ssSetInputPortWidth(S, 0, MAX_CHANNEL_TAPS);
    ssSetInputPortWidth(S, 1, MAX_CHANNEL_TAPS);
    ssSetInputPortDirectFeedThrough(S, 0, 1);
    ssSetInputPortDirectFeedThrough(S, 1, 1);

    if (!ssSetNumOutputPorts(S, 3)) return;
    ssSetOutputPortWidth(S, 0, MAX_CHANNEL_TAPS);   
    ssSetOutputPortWidth(S, 1, MAX_CHANNEL_TAPS);   
    ssSetOutputPortWidth(S, 2, 1);

    ssSetNumSampleTimes(S, 1);

    ssSetSFcnParamNotTunable(S,0); /* nopeuttaa, kun vakio parametrit*/ 
    ssSetSFcnParamNotTunable(S,1);  

    /* Take care when specifying exception free code - see sfuntmpl.doc */
    ssSetOptions(S, SS_OPTION_EXCEPTION_FREE_CODE);
}   /* ei saa kayttaa mxCalloc tai mexErrMsgTxt tms rutiineita */


/* Function: mdlInitializeSampleTimes =========================================
 */
static void mdlInitializeSampleTimes(SimStruct *S)
{
  ssSetSampleTime(S, 0, td); 
  ssSetOffsetTime(S, 0, 0.0);
}



/* Function: mdlOutputs =======================================================
 */
static void mdlOutputs(SimStruct *S, int_T tid)
{
  real_T            *channel = ssGetOutputPortRealSignal(S,0);
  real_T            *delay = ssGetOutputPortRealSignal(S,1);
  real_T            *length    = ssGetOutputPortRealSignal(S,2);
  InputRealPtrsType aPtrs = ssGetInputPortRealSignalPtrs(S,0);
  InputRealPtrsType dPtrs = ssGetInputPortRealSignalPtrs(S,1);
  int_T             i,i_tmp;            
  real_T             channel_threshold = mxGetPr(THRES(S))[0]  ; 
  
  i_tmp =0;
  for (i = 0; i < MAX_CHANNEL_TAPS; i++){
    if (A(i) > channel_threshold) {
      channel[i_tmp] = A(i);
      delay[i_tmp] = D(i);
      i_tmp ++;
    }
  }
  length[0] = i_tmp;
}
/* Function: mdlTerminate =====================================================
 */
static void mdlTerminate(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