digital filter code.txt

圆周卷积滤波器

#include "iostream.h"
#include "fstream.h"
#include "string.h"
#include "math.h"
void DFB(int N, double signal[],double Xr[],double Xi[],double spec[]);
void bandf(double h[],int Nh);
void conv(double xin[], double h[], int Nh, double xout[]);
void main()
{
	ofstream myfile;
	char filename[20];
	char extname[]=".dat";
	cout<<"请输入保存文件名：";
	cin>>filename;
	strcat(filename,extname);

    myfile.open(filename);

   const int N=631;
   const int Nh=631;
   
   
   const int lout=631;
   
   double pi=3.1415926;
   double /*signal[N],*/Xr[lout],Xi[lout],spec[lout];
   double h[Nh];
   double xin[lout]; double xout[lout];
   int i,m;
   double Tp,fs;
   Tp=0.01;fs=300;
   //for(i=0;i<N;i++)
/*{1,2,0,1,2,3,2,1,2,1,2,3,2,
		2,3,2,1,3,3,2,1,3,2,1,3,2,3,2,3,2,1,3,2,
		0,3,2,0,3,2,1,0,3,2,0,3,2,1,3,2,1,3,2,1,
		3,2,1,3,2,3,0};*/

double signal[631]=/*{1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
	   1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
	   1,1,1,1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
	   0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};*/

{3.7493,    4.6798,    3.8025,    4.6638,    1.2380,    3.4825  ,  1.4487 ,   3.2318  ,  2.2772,    4.8320,    1.0516,    2.3844,    4.3789,    4.9308,    3.4079,    1.3558,    4.8068,    2.7732,    1.0569,    2.4996 ,   4.0662,    2.2416,    1.6641,    2.4710,    4.2266,    2.0142,    2.0852,    3.5600,    2.8671  ,  3.3847 ,   4.4712   , 3.6645,    4.1163,
    1.6225,    3.4832 ,   3.8143  ,  4.4938,    2.6363   , 1.9893   , 1.0587 ,   4.2648   , 2.4887  ,  1.5238  ,  2.2292,
    1.7645,    3.9251 ,   2.9399 ,   3.0536  ,  2.8962  ,  2.4108 ,   3.6562  ,  4.9084 ,   1.2948,    1.3817   , 4.7067,
    2.6898 ,   1.7756   , 1.4585  ,  3.9306 ,   4.6360  ,  1.7514 ,   3.8962 ,   1.8876,    1.7994  ,  1.0595 ,   3.7149,
    4.4239,    4.6192 ,   3.6594 ,   2.6889 ,   3.3850 ,   2.9626  ,  2.1265 ,   3.8147 ,   1.1980 ,   2.1528   , 1.2973,
    2.9610 ,   3.2768 ,   2.4615  ,  4.8455,    2.3158  ,  2.6371   , 2.0473  ,  3.0882   , 3.2668 ,   4.2669 ,   1.2827,
    4.2637 ,   3.5272 ,   1.5602,    1.2882   , 2.9128  ,  2.8541  ,  3.8339,    4.7316 ,   1.4877  ,  4.9419 ,   1.0477,
    2.8431 ,   1.9377,    3.2671 ,   3.2136,    3.3887,    3.4438,    4.1354 ,   3.8534,    3.0884 ,   1.0695 ,   1.9086,
    2.8294 ,   3.1951   , 4.2920   , 2.1679  ,  1.6458   , 1.2847  ,  4.9446  ,  1.9122 ,   1.4682,    4.2776 ,   3.0650,
    2.8028 ,   4.7263 ,   3.6958   , 4.4319 ,   4.3179   , 2.2571   , 2.8934  ,  2.7986 ,   4.0797  ,  3.4846,    2.8328,
    2.6489,    2.3408 ,   4.9978,    2.3430   , 4.8245   , 3.4335 ,   4.6113  ,  1.6888  ,  2.5002 ,   3.2409 ,   3.8128,
    4.6064,    3.6221   , 4.8465 ,   3.7208  ,  3.3822  ,  1.7001  ,  2.8042 ,   4.8753  ,  4.2935 ,   1.9761  ,  3.3299,
    1.0223,    2.5676  ,  1.2354  ,  1.2138   , 1.1150   , 3.4841  ,  4.2181  ,  2.4229   , 1.1865,    4.2880  ,  3.0368,
    2.1896 ,   3.5093 ,   2.4412   , 2.4266,    4.2485  ,  1.9838  ,  4.3155   , 1.1962  ,  3.3917,    2.0528 ,   1.2972,
    1.1966  ,  3.7963 ,   3.1941  ,  2.9932,    3.4405  ,  3.3494   , 1.6651  ,  4.0214  ,  4.7966,    4.0145,    1.7729,
    3.7727,    2.5887,    2.0471 ,   2.7378  ,  3.8060  ,  3.0242  ,  2.5756  ,  4.5793 ,   2.1552,    3.6386 ,   2.5184,
    3.6004,    2.6545,    3.3894,    3.2498  ,  1.3688  ,  2.8591  ,  3.0830  ,  2.1446 ,   4.5553 ,   1.8563   , 2.1057,
    4.9320  ,  3.6209,    1.1971,    3.4665  ,  2.6996  ,  3.1657  ,  3.8725   , 2.0048  ,  1.4063  ,  3.4085    ,4.0835,
    3.2107   , 4.3503,    3.2842  ,  1.4534  ,  2.5023   , 4.7693   , 3.2768  ,  4.7309 ,   1.2613   , 3.4197   , 2.2557,
    2.6003  ,  2.4864,    3.8034   , 4.5930  ,  1.6646   , 2.3670   , 2.8432  ,  1.5239 ,   1.9372    ,3.6380    ,3.5528,
    1.7952   , 2.7010,    4.8492,    4.0182 ,   4.3326   , 2.6072  ,  2.7812   , 4.7633 ,   4.7324    ,1.7335   , 4.9463,
    3.5008  ,  3.3787,    4.0021  ,  4.1645  ,  4.3546  ,  2.2308  ,  1.3510   , 3.8074 ,   1.2525    ,3.5462    ,3.0115,
    3.9335   , 3.2630,    3.9600  ,  4.2598 ,   2.8065   , 2.6463  ,  2.7739   , 4.3907  ,  2.0569   , 1.6812    ,4.7908,
    2.5035   , 3.8662,    2.7275  ,  3.6800 ,   4.8264   , 2.1438  ,  2.4652   , 1.8371  ,  4.9981   , 3.1584   , 4.3121,
    1.0395  ,  3.0452,    3.5371  ,  1.8035 ,   1.5886  ,  2.5765  , 2.2101  ,  2.8204  ,  1.8480   , 3.4936    ,4.6702,
    2.6794   , 4.1056,    4.2121  ,  2.0924  ,  4.4797   , 3.0121  ,  4.4074   , 1.3243   , 2.9936   , 3.7436   , 1.4523,
    4.0147  ,  2.9574,    1.3355 ,   3.5049 ,   4.0777    ,3.8879  ,  4.0379   , 4.4045  ,  2.1620    ,3.7094    ,4.2485,
    4.1755   , 1.7436,    4.7819 ,   3.1474 ,   2.7766   , 2.2248  ,  4.7990   , 3.2482   , 3.6910   , 4.5073    ,4.6331,4.6331};



/*{-1,-2,0,1,2,3,2,1,-2,1,2,3,2,-2,3,2,1,3,-3,2,1,-3,2,1,3,2,3,2,3,2,1,3,2,
		0,3,2,0,3,2,1,0,-3,2,0,-3,2,1,3,-2,1,3,-2,1,3,-2,1,3,2,-3,0};*/


/*{1,2,0,1,2,3,2,1,2,1,2,3,2,
		2,3,2,1,3,3,2,1,3,2,1,3,2,3,2,3,2,1,3,2,
		0,3,2,0,3,2,1,0,3,2,0,3,2,1,3,2,1,3,2,1,
		3,2,1,3,2,3,0}*/;/*{1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,
	   1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,
	   1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0,1,1,0,0};*/

	   //signal[i]=sin((2*pi)/(Tp*fs)*i);//signal[i]=sin((2*pi/N)*n)
   //DFB(N,signal,Xr,Xi,spec);
   /*for(j=0;j<N;j++)
   {
	   cout<<"spec["<<j<<"]="<<spec[j]<<endl;
	   myfile<<j<<"     "<<spec[j]<<endl;
   }*/
   bandf(h,Nh);
   for(m=0;m<Nh;m++)
   {
	   
	   myfile<<m<<"     "<<h[m]<<endl;
   }
  conv(signal,h,Nh,xout);
  for(i=0;i<lout;i++)
   {
	   cout<<"signal[n]*h[n]="<<xout[i]<<endl;
	   myfile<<i<<"     "<<xout[i]<<endl;
	   xin[i]=xout[i];
   }
   DFB(lout,xin,Xr,Xi,spec);
   for(m=0;m<lout;m++)
   {
	   cout<<"spec["<<m<<"]="<<spec[m]<<endl;
	   myfile<<m<<"     "<<spec[m]<<endl;
   }
	
}
void DFB(int N, double x[],double Xr[],double Xi[],double spec[])
{
	double pi=3.1415926;
	int n,k;
	double realsum,imagsum;

	for(k=0;k<N;k++)
	{
		realsum=0.0;
        imagsum=0.0;
	
		for(n=0;n<N;n++)
		{
         realsum+=x[n]*cos((2*pi/N)*n*k);
         imagsum+=x[n]*sin((2*pi/N)*n*k);
		 }
		Xr[k]=realsum;
		Xi[k]=imagsum;
		spec[k]=sqrt(Xr[k]*Xr[k]+Xi[k]*Xi[k]);
	}
	
	
}
//////
void bandf(double h[],int Nh)
{
	int n,a;
	
	double pi=3.1415926;
	double wc,wo;
	
	a=(Nh-1)/2;
	
	wc=0.2*pi;
	wo=0.5*pi;
	
	 for(n=0;n<Nh;n++)
	 {
		 if(n!=a)
		 
h[n]=(0.54-0.46*cos(2*pi*n/(Nh-1)))*(2/(pi*(n-a)))*sin((n-a)*wc)*cos((n-a)*wo);
        else
		 h[n]=(0.54-0.46*cos(2*pi*n/(Nh-1)))*(2*wc/pi)*cos((n-a)*wo);
		 cout<<"h["<<n<<"]="<<h[n]<<endl;
	 }
}
/////
void conv(double xin[], double h[], int Nh, double xout[])
{
  int n,m; 
  double sum;
  for (n = 0; n <Nh; n++)
  {
      sum = 0.0;
      for(m = 0; m <Nh; m++)
	  {
	   if(n-m>=0)
          sum+= xin[m]*h[n-m];
	   else
		  sum+=xin[m]*h[Nh+n-m];
       
	  }
	  xout[n]=sum;
  }
	for(n=0;n <Nh; n++)
	{
		cout<<"xin[n]*h[n]="<<xout[n]<<endl;

	}
}