jens
0179c510fe
git-svn-id: http://moon:8086/svn/software/trunk/libsrc/fir@1 b431acfa-c32f-4a4a-93f1-934dc6c82436
75 lines
1.5 KiB
C
Executable File
75 lines
1.5 KiB
C
Executable File
/*************************************************************************/
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/* fir.c
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/*************************************************************************/
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#include <stdio.h>
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#include <malloc.h>
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#include "math.h"
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#include "fir.h"
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#include "firinterp.h"
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/*************************************************************************/
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/* Global Variables
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/*************************************************************************/
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int FIfilter(struct _sFIRIP *pObj, float *pX, float *pY, int len)
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{
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int n, len2, k, i, j, nIp, firLen, kL;
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float *pSxt, *pBt, sum;
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kL = pObj->kL;
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nIp = pObj->nCoefPerPhase;
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firLen = pObj->firLen;
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pBt = &pObj->pB[0];
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pSxt = &pObj->pX[0];
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len2 = 0;
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for (n=0; n < len; n++)
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{
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for (i=nIp; i > 0; i--)
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pSxt[i] = pSxt[i-1];
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pSxt[0] = pX[n];
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for (k=0; k < kL; k++)
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{
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sum = 0.0;
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i=0;
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for (j=k; j < firLen; j += kL)
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{
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sum += pSxt[i] * pBt[j];
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i++;
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}
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*(pY++) = sum;
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len2++;
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}
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}
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return len2;
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}
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void FIinit(struct _sFIRIP *pObj, int kL, int nCoefPerPhase)
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{
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int n;
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pObj->kL = kL;
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pObj->firLen = kL*nCoefPerPhase;
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pObj->nCoefPerPhase = nCoefPerPhase;
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if ((pObj->firLen%2) == 0)
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pObj->firLen++;
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pObj->pB = (float*)malloc(pObj->firLen*sizeof(float));
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pObj->pX = (float*)malloc((pObj->nCoefPerPhase+1)*sizeof(float));
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for(n=0; n <= pObj->nCoefPerPhase; n++)
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{
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pObj->pX[n] = 0;
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}
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Sinc(pObj->pB, kL, 1.f, 1.f/kL, pObj->firLen);
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}
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void FIfree(struct _sFIRIP *pObj)
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{
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free(pObj->pB);
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free(pObj->pX);
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} |