randomization.cpp

在vc上做的802.16d ofdm phy的仿真

#include "typedef.h"
#include "randomization.h"
#include "global_var.h"

//initializtion RandVector
void dlRandInit(Uint16 burstIndex,	//0=FCH, indication that the burst is FCH.
					//1= indication that this is theburst #1after FCH.
				Uint8  	bsid,         
				Uint8 	diuc,
				Uint8	frameIndex,	
				Uint16  *pRandVector)
{
	if(burstIndex < 2)
	{
		*pRandVector = 0x4a80;
	}
	else
	{
		*pRandVector = (Uint16)(frameIndex & 0x0f);
		*pRandVector |= ((diuc & 0x0f) << 5);
		*pRandVector |= 0x0610;
		*pRandVector |= ((bsid & 0x0f)<< 11);
	}
}


//randomization
void randomization (Uint8 mode,
					DlTxBurstParam *pDlTxBurstParam,
					Uint16 burstIndex,
					Uint8  *pRandomizationIn,         
					Uint16  randomizationInLength,   
					Uint16  *pRandVector,                  
   					Uint8  *pRandomizationOut) 
{
	Int16 i, j;

	Int8  feedBack;
	
	if((*pDlTxBurstParam).burstSymIndex == 0)
	{
		dlRandInit(burstIndex,(*pDlTxBurstParam).bsid,
			(*pDlTxBurstParam).diuc,(*pDlTxBurstParam).frameIndex,pRandVector);
	}
	for (i = 0; i < randomizationInLength; i++)
	{
       	pRandomizationOut[i] = pRandomizationIn[i];
		for (j = 0; j < 8; j++)
		{
			feedBack  = (*pRandVector & 1);
			*pRandVector  >>= 1;
			feedBack ^= (*pRandVector & 1);
			pRandomizationOut[i] ^= feedBack << (7 - j);//"<<" before "^" ;
         	*pRandVector ^= (feedBack << 14);
		}
	}
		
}