channel.cpp

扩展的直序扩频系统

#include "Common.h"

extern float SNR;

void Channel()
{
	int i=0,CycleNum=0,p=0;
	complex ChannelOut[CHIP_SIZE]={0.f, 0.f};
	complex ChannelMem[MemLength]={0.f, 0.f};
	complex Channel_ImpRep[MULTIPATH_NUM]={0.f, 0.f};
	float Ps=0.f;
	FILE *fpt_ChannelIn, *fpt_ChannelOut;

	if(( fpt_ChannelIn=fopen("TxSignal.dat","rb") ) == NULL)
	{
		printf("Can not open TxSignal.dat\n");
		return;
	}
	else
	{
		fpt_ChannelOut=fopen("RxSignal.dat","wb");

		#if(MULTIPATH_flag == 1)
			GenChannel(Channel_ImpRep);    //generate the multipath channel
		#endif

		for(i=0; i<TOTAL_CHIP; i++)     //CHIP_SIZE should be 1
		{
			memset(ChannelOut, 0, CHIP_SIZE*sizeof(complex));
			fread(ChannelOut, CHIP_SIZE*sizeof(complex), 1, fpt_ChannelIn);

			#if(MULTIPATH_flag == 1)
				AddMutiChannel(ChannelOut, Channel_ImpRep, ChannelMem, CHIP_SIZE);
			#endif

			Ps = (float)BPS/(float)(CHIP_SIZE);
			
			AddGaussNoise(ChannelOut, Ps, CHIP_SIZE);
			
            #if(OFFSET_flag == 1)
		    	AddFrequencyOffset(ChannelOut,i);                              // Add Frequency offset 
            #endif
			
			fwrite(ChannelOut, sizeof(complex), CHIP_SIZE, fpt_ChannelOut);			
		}
		fclose(fpt_ChannelOut);
	}	
	fclose(fpt_ChannelIn);
}