mpsk_module.h

M进制调制

#include <stdio.h>
#include <math.h>
#include <time.h>
#include <stdlib.h>
//#include "rand.h"
#define PI 3.1415926



//to create Message bits , which has a length of N		
Random_Bits(Message,N);

//to modulate 
MPSK_Modulate(Message,Modulated_Symbol,length);

//to add AWGN_Noise
TRAN_AWGN(Modulated_Symbol,Rec_Value,length);

//to demodulate
MPSK_Demodulate(Rec_Value,DeM_Code,length);


void Random_Bits(char *,int);    //to create Message Bits, which has a length of N
void MPSK_Modulate(char *,struct plural *,int,int);
void TRAN_AWGN(struct plural *,struct plural *,int);
void MPSK_Demodulate(struct plural *,char *,int);
int Bin_to_Deci(char *,int);     //to change binary system to the decimal system 
void Display_char(char *,int);
void Display_plural(struct plural *,int);

void Display_char(char *temp, int length,int n)
{
	FILE *fp;
	int i,j;

	fp=fopen("check.txt","a");
	for(i=0;i<length;i++)
	{
		if(i%n==0)
		{
			printf("\t");
			fprintf(fp,"\t");
		}
		printf("%c",temp[i]);
		fprintf(fp,"%c",temp[i]);
	}

	fclose(fp);
}


void Display_plural(struct plural *temp, int length)
{
	FILE *fp;
	int i;

	fp=fopen("check.txt","a");
	for(i=0;i<length;i++)
	{
		printf("%lf  +  %lf  i\n",temp[i].real,temp[i].imag);
		fprintf(fp,"%lf  +  %lf  i\n",temp[i].real,temp[i].imag);
	}

	fclose(fp);
}

//产生长度为N的随机信息比特
void Random_Bits(char *Message,int N)
{
	int i;
	srand((unsigned int)time(NULL));

	for(i=0;i<N;i++)
	{
		Message[i]=rand()%2;
	}
}

//二进制转换函数, 将连续n个比特转换成十进制结果并返回
int Bin_to_Deci(char *temp,int n)
{
	int i;
	int sum=0;

	for(i=0;i<n;i++)
	{
		if(temp[i])
		{
			sum += pow(2,i);
		}
	}

	return sum;
}



//将连续n个比特进行MPSK调制，调制结果保存在Modulated_Symbol中
void MPSK_Modulate(
char *Message,                     //待调制的码
struct plural *Modulated_Symbol,   //调制后的码
int length,                        //调制后码元的长度
int n                              //M进制可以用n个比特来表示
)
{
	int i,j;
	char *temp;  //用来临时记录n个连续比特，以方便将它们对应转化成十进制
	int value;   //记录n个比特所对应的十进制数字

	temp=(char *)malloc(n*sizeof(char));
	
	if(n==4)
	{
		for(i=0;i<length;i++)
		{
			for(j=0;j<n;j++)
			{
				temp[j]=Message[n*i+j];
			}
			value=Bin_to_Deci(temp,n);
			switch(value)
			{
			case 0:evaluate(&Modulated_Symbol[i],0);
				break;
			case 1:evaluate(&Modulated_Symbol[i],1);
				break;
			case 2:evaluate(&Modulated_Symbol[i],3);
				break;
			case 3:evaluate(&Modulated_Symbol[i],2);
				break;
			case 4:evaluate(&Modulated_Symbol[i],7);
				break;
			case 5:evaluate(&Modulated_Symbol[i],6);
				break;
			case 6:evaluate(&Modulated_Symbol[i],4);
				break;
			case 7:evaluate(&Modulated_Symbol[i],5);
				break;
			case 8:evaluate(&Modulated_Symbol[i],15);
				break;
			case 9:evaluate(&Modulated_Symbol[i],14);
				break;
			case 10:evaluate(&Modulated_Symbol[i],12);
				break;
			case 11:evaluate(&Modulated_Symbol[i],13);
				break;
			case 12:evaluate(&Modulated_Symbol[i],8);
				break;
			case 13:evaluate(&Modulated_Symbol[i],9);
				break;
			case 14:evaluate(&Modulated_Symbol[i],11);
				break;
			case 15:evaluate(&Modulated_Symbol[i],10);
				break;
			}
		}
	}



}


void evaluate(struct plural *temp,int value)
{
	temp.real=cos((double)value/(double)16*2*PI);
	temp.imag=sin((double)value/(double)16*2*PI);
}