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53f3a2bc1aa4c4cf624fa2dbf40da1e440879cc1
radio/symbol.c
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jens 290fd5f5e0 Initial import 
git-svn-id: http://moon:8086/svn/software/trunk/libsrc/radio@1 b431acfa-c32f-4a4a-93f1-934dc6c82436
2014-07-19 07:44:42 +00:00

298 lines
7.5 KiB
C
Executable File
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// --------------------------------------------------------------
#include <stdio.h> // for SymStatPrint() remove later
#include <string.h>
#include <malloc.h>
#include <math.h>
#include "radio_types.h"
#include "symbol.h"
// --------------------------------------------------------------
// Symbol demapper for receiver works on each symbol
// --------------------------------------------------------------
void SymMapInit(sym_map_t *pObj, uint32_t nBitsPerSym, uint32_t type)
{
cpx_t iq;
uint32_t i, j, k, m, n, u, Ns, Nq, Nsq, map_idx_i, map_idx_q;
radio_float_t phi, dphi, ii, qq, iii, qqq, temp, stepIQ;
radio_float_t mag, E_m2, E_m2_c, E_m4;
radio_float_t c_smma;
cpx_t E_a4;
int signI[4] = {+1, -1, -1, +1};
int signQ[4] = {+1, +1, -1, -1};
int even;
pObj->nBitsPerSym = nBitsPerSym;
pObj->num_const = 1;
pObj->type = type;
pObj->iq_step = 0;
pObj->iq_max = 0;
pObj->Pref = 0;
E_a4 = Cpx(0,0);
c_smma = (radio_float_t)1; // Tuning constant S-MMA
for(k=0; k < nBitsPerSym; k++)
{
pObj->num_const *= 2;
}
pObj->pMapTbl = (map_t*)malloc(pObj->num_const*sizeof(map_t));
pObj->ppMapTbl = NULL;
Ns = (uint32_t)sqrt((radio_float_t)pObj->num_const);
Nq = pObj->num_const/4;
Nsq = (uint32_t)sqrt((radio_float_t)Nq);
stepIQ = (radio_float_t)sqrt(2.0)/(Ns-1);
E_m2_c = E_m2 = E_m4 = 0;
switch(type)
{
case MAP_MODE_PSK:
pObj->Es = 1.0; // Symbol transmit power
pObj->Eb = pObj->Es/nBitsPerSym;
pObj->Pref = (radio_float_t)(1.0/sqrt(2.0));
dphi = 2*(radio_float_t)PI/pObj->num_const;
phi = (radio_float_t)PI/pObj->num_const;
for (k=0; k < pObj->num_const; k++)
{
iq.real = (radio_float_t)cos(phi);
iq.imag = (radio_float_t)sin(phi);
pObj->pMapTbl[k].phi = (radio_float_t)CpxPhiS(iq);
pObj->pMapTbl[k].mag = (radio_float_t)CpxMagS(iq);
pObj->pMapTbl[k].rect = iq;
phi += dphi;
}
break;
case MAP_MODE_QAM:
pObj->Es = (radio_float_t)0.5*stepIQ*stepIQ;
pObj->Eb = pObj->Es/nBitsPerSym;
pObj->ppMapTbl = (map_t**)malloc(Ns*sizeof(map_t*));
for (i=0; i< Ns; i++)
pObj->ppMapTbl[i] = (map_t*)malloc(Ns*sizeof(map_t));
ii = (radio_float_t)(1.0/sqrt(2.0));
pObj->iq_max = ii;
qq = ii;
even = 1;
k = 0;
for (m=0; m < Nsq; m++)
{
for (n=0; n < Nsq; n++)
{
iii = ii;
qqq = qq;
for (j=0; j < 4; j++)
{
u = Nq*j+k;
iq.real = iii*signI[j];
iq.imag = qqq*signQ[j];
mag = (radio_float_t)CpxMagS(iq);
phi = (radio_float_t)CpxPhiS(iq);
pObj->pMapTbl[u].mag = mag;
pObj->pMapTbl[u].phi = phi;
pObj->pMapTbl[u].rect = iq;
E_m2_c += (radio_float_t)pow(mag, 2+c_smma);
E_m2 += (radio_float_t)pow(mag, 2);
E_m4 += (radio_float_t)pow(mag, 4);
E_a4.real += (radio_float_t)pow(iq.real, 4);
E_a4.imag += (radio_float_t)pow(iq.imag, 4);
temp = iii;
iii = qqq;
qqq = temp;
map_idx_i = (int)(0.5 +(0.5*iq.real/pObj->iq_max + 0.5)*(Ns-1));
map_idx_q = (int)(0.5 +(0.5*iq.imag/pObj->iq_max + 0.5)*(Ns-1));
pObj->ppMapTbl[map_idx_i][map_idx_q].mag = mag;
pObj->ppMapTbl[map_idx_i][map_idx_q].phi = phi;
pObj->ppMapTbl[map_idx_i][map_idx_q].rect = iq;
pObj->ppMapTbl[map_idx_i][map_idx_q].sym = (symbol_t)u;
}
ii = ii - even*stepIQ;
k++;
}
qq = qq - stepIQ;
ii = ii + even*stepIQ;
even = -even;
}
switch(pObj->num_const)
{
// QPSK
case 4:
pObj->Pref = (radio_float_t)0.707;
break;
// 16-QAM
case 16:
pObj->Pref = (radio_float_t)0.385;
break;
// 64-QAM
case 64:
pObj->Pref = (radio_float_t)0.31;
break;
// 256-QAM
case 256:
pObj->Pref = (radio_float_t)0.27;
break;
default:
break;
}
break;
default:
break;
}
pObj->iq_step = stepIQ;
pObj->iq_side_len = Ns;
pObj->R2_cma = E_m4/E_m2;
pObj->R_mma.real = 2*E_a4.real/E_m2;
pObj->R_mma.imag = 2*E_a4.imag/E_m2;
pObj->R_smma.real = 2*E_a4.real/E_m2_c;
pObj->R_smma.imag = 2*E_a4.imag/E_m2_c;
}
void SymMapFree(sym_map_t *pObj)
{
uint32_t i;
if (pObj->pMapTbl)
{
free(pObj->pMapTbl);
pObj->pMapTbl = NULL;
}
if (pObj->ppMapTbl)
{
for (i=0; i< (uint32_t)sqrt((float)pObj->num_const); i++)
free(pObj->ppMapTbl[i]);
free(pObj->ppMapTbl);
pObj->ppMapTbl = NULL;
}
}
void SymMapReinit(sym_map_t *pObj, uint32_t nBitsPerSym, uint32_t type)
{
SymMapFree(pObj);
SymMapInit(pObj, nBitsPerSym, type);
}
cpx_t SymMapMap(sym_map_t *pObj, symbol_t symbol)
{
if (symbol >= pObj->num_const)
return Cpx(0,0);
return pObj->pMapTbl[(uint32_t)symbol].rect;
}
symbol_t SymMapDemap(sym_map_t *pObj, cpx_t x)
{
uint32_t map_idx_i, map_idx_q;
radio_float_t rx_i, rx_q;
rx_i = dclamp(x.real, -pObj->iq_max, pObj->iq_max);
rx_q = dclamp(x.imag, -pObj->iq_max, pObj->iq_max);
map_idx_i = (int)(0.5 +(0.5*rx_i/pObj->iq_max + 0.5)*(pObj->iq_side_len-1));
map_idx_q = (int)(0.5 +(0.5*rx_q/pObj->iq_max + 0.5)*(pObj->iq_side_len-1));
return pObj->ppMapTbl[map_idx_i][map_idx_q].sym;
}
map_t SymMapGetSymbolInfo(sym_map_t *pObj, symbol_t symbol)
{
return pObj->pMapTbl[(uint32_t)symbol];
}
sym_err_t SymMapGetError(sym_map_t *pObj, cpx_t x, symbol_t symbol)
{
map_t map;
sym_err_t res;
map = SymMapGetSymbolInfo(pObj, symbol);
res.err_mag = map.mag - (radio_float_t)CpxMagS(x);
res.err_phi = map.phi - (radio_float_t)CpxPhiS(x);
res.err = CpxSubS(map.rect, x);
res.mag = CpxMagS(x);
res.phi = CpxPhiS(x);
res.soft_sym = x;
res.hard_sym = map.rect;
res.hard_mag = map.mag;
res.hard_phi = map.phi;
return res;
}
// --------------------------------------------------------------
void SymStatInit(sym_stat_t *pObj, uint32_t nBitsPerSym)
{
uint32_t i;
memset(pObj, 0, sizeof(sym_stat_t));
pObj->num_const = 1;
for(i=0; i < nBitsPerSym; i++)
{
pObj->num_const *= 2;
}
pObj->pPerSymStat = (per_sym_stat_t*)malloc(pObj->num_const*sizeof(per_sym_stat_t));
for(i=0; i < pObj->num_const; i++)
{
pObj->pPerSymStat[i].count = 0;
pObj->pPerSymStat[i].var_err_mag = 0;
pObj->pPerSymStat[i].var_err_phi = 0;
SlidingVarInit(&pObj->pPerSymStat[i].sl_err_mag, 1000, 1000);
SlidingVarInit(&pObj->pPerSymStat[i].sl_err_phi, 1000, 1000);
}
}
void SymStatFree(sym_stat_t *pObj)
{
if(pObj->pPerSymStat)
free(pObj->pPerSymStat);
pObj->pPerSymStat = 0;
}
void SymStatReset(sym_stat_t *pObj)
{
uint32_t i;
pObj->sym_cnt = 0;
for(i=0; i < pObj->num_const; i++)
{
pObj->pPerSymStat[i].count = 0;
}
}
void SymStatUpDate(sym_stat_t *pObj, symbol_t sym, sym_err_t *pSym_err)
{
// Statistics
pObj->sym_cnt++;
pObj->pPerSymStat[sym].count++;
pObj->pPerSymStat[sym].p = (radio_float_t)pObj->pPerSymStat[sym].count/pObj->sym_cnt;
pObj->pPerSymStat[sym].var_err_mag = SlidingVarProcess(&pObj->pPerSymStat[sym].sl_err_mag, pSym_err->err_mag);
pObj->pPerSymStat[sym].var_err_phi = SlidingVarProcess(&pObj->pPerSymStat[sym].sl_err_phi, pSym_err->err_phi);
}
void SymStatPrint(sym_stat_t *pObj)
{
uint32_t i;
printf("Number of constellations : %d\n", pObj->num_const);
printf("Number of total symbols : %d\n", pObj->sym_cnt);
printf("Sym#\tOccur.\t\tProb.\t\tVar(MagErr)[dB]\tVar(PhiErr/PI)[dB]\n");
for(i=0; i < pObj->num_const; i++)
{
printf("%4.1d\t%6.d\t\t%1.2g\t\t%.2f\t\t%.2f\n",
i,
pObj->pPerSymStat[i].count,
pObj->pPerSymStat[i].p,
10*log10(pObj->pPerSymStat[i].var_err_mag),
10*log10(pObj->pPerSymStat[i].var_err_phi/(PI*PI)));
}
}
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