Esempio n. 1
0
	mGold()
	{
	Parser p(std::string("config.txt"));
	numG=p.get_int("numG");
	p1.set_length(25);
	p2.set_length(25);
	
	ps1.set_length(numG);
	ps2.set_length(numG);
	
	c1.set_length(numG);
	c2.set_length(numG);

	cv1.set_length(numG);
	cv2.set_length(numG);
	c.set_length(numG);
	cConjugate.set_length(numG);
	p1.zeros();
	p2.zeros();
	p1[0]=1;
	p2[0]=1;
	}
Esempio n. 2
0
	transmiter()
	{
		Parser p(std::string("config.txt"));
		DPCCH_NBits=p.get_int("DPCCH_NBits");
		
		HS_DPCCH_NBits=p.get_int("HS_DPCCH_NBits");
		E_DPCCH_NBits=p.get_int("E_DPCCH_NBits");
		E_DPDCH1_NData=p.get_int("E_DPDCH1_NData");
		E_DPDCH2_NData=p.get_int("E_DPDCH2_NData");
		E_DPDCH3_NData=p.get_int("E_DPDCH3_NData");
		E_DPDCH4_NData=p.get_int("E_DPDCH4_NData");
		SF=p.get_int("SF");
		SF_EDPDCH2=p.get_int("SF_EDPDCH2");
		SF_EDPDCH3=p.get_int("SF_EDPDCH3");
		DPCCH_SLOT0=p.get_int("DPCCH_SLOT0");
		DPCCH_SLOT1=p.get_int("DPCCH_SLOT1");
		DPCCH_SLOT2=p.get_int("DPCCH_SLOT2");
		DPCCH_SLOT3=p.get_int("DPCCH_SLOT3");
		DPCCH_SLOT4=p.get_int("DPCCH_SLOT4");
		DPCCH_SLOT5=p.get_int("DPCCH_SLOT5");
		DPCCH_SLOT6=p.get_int("DPCCH_SLOT6");
		DPCCH_SLOT7=p.get_int("DPCCH_SLOT7");
		DPCCH_SLOT8=p.get_int("DPCCH_SLOT8");
		DPCCH_SLOT9=p.get_int("DPCCH_SLOT9");
		DPCCH_SLOT10=p.get_int("DPCCH_SLOT10");
		DPCCH_SLOT11=p.get_int("DPCCH_SLOT11");
		DPCCH_SLOT12=p.get_int("DPCCH_SLOT12");				
		DPCCH_SLOT13=p.get_int("DPCCH_SLOT13");
		DPCCH_SLOT14=p.get_int("DPCCH_SLOT14");
		 
		betaDPCCH=p.get_int("betaDPCCH");
		betaE_DPDCH1=p.get_int("betaE_DPDCH1");
		betaE_DPDCH2=p.get_int("betaE_DPDCH2");
		betaE_DPDCH3=p.get_int("betaE_DPDCH3");
		betaE_DPDCH4=p.get_int("betaE_DPDCH4");
		betaE_DPCCH=p.get_int("betaE_DPCCH");
		betaE_HS_DPCCH=p.get_int("betaE_HS_DPCCH");
	
		betaDPCCHlin=pow10(betaDPCCH/10.0);
		betaE_DPDCH1lin=pow10(betaE_DPDCH1/10.0);
		betaE_DPDCH2lin=pow10(betaE_DPDCH2/10.0);
		betaE_DPDCH3lin=pow10(betaE_DPDCH3/10.0);
		betaE_DPDCH4lin=pow10(betaE_DPDCH4/10.0);
		betaE_DPCCHlin=pow10(betaE_DPCCH/10.0);
		betaE_HS_DPCCHlin=pow10(betaE_HS_DPCCH/10.0);

		OVSF=wcdma_spreading_codes (SF);
		OVSF4=wcdma_spreading_codes(SF_EDPDCH3);
		OVSF2=wcdma_spreading_codes(SF_EDPDCH2);

		OVSF256_0.set_length(SF,false);
		OVSF256_1.set_length(SF,false);
		OVSF256_33.set_length(SF,false);
		OVSF256_64.set_length(SF,false);
		
		OVSF4_1.set_length(SF_EDPDCH3,false);
		OVSF4_3.set_length(SF_EDPDCH3,false);
		OVSF2_1.set_length(SF_EDPDCH2,false);

		for(int i=0;i<OVSF.cols();i++)
		{
		OVSF256_0[i]=OVSF(0,i);
		OVSF256_1[i]=OVSF(1,i);
		OVSF256_33[i]=OVSF(33,i);
		OVSF256_64[i]=OVSF(64,i);
		
		}
		for(int i=0;i<OVSF4.cols();i++)
		{
			OVSF4_1[i]=OVSF4(1,i);
		
		
		}

		for(int i=0;i<OVSF2.cols();i++)
		{
			OVSF2_1[i]=OVSF2(1,i);
		}
		bvec DPCCH0=dec2bin(DPCCH_SLOT0,true);
		bvec DPCCH1=dec2bin(DPCCH_SLOT1,true);
		bvec DPCCH2=dec2bin(DPCCH_SLOT2,true);
		bvec DPCCH3=dec2bin(DPCCH_SLOT3,true);
		bvec DPCCH4=dec2bin(DPCCH_SLOT4,true);
		bvec DPCCH5=dec2bin(DPCCH_SLOT5,true);
		bvec DPCCH6=dec2bin(DPCCH_SLOT6,true);
		bvec DPCCH7=dec2bin(DPCCH_SLOT7,true);
		bvec DPCCH8=dec2bin(DPCCH_SLOT8,true);
		bvec DPCCH9=dec2bin(DPCCH_SLOT9,true);
		bvec DPCCH10=dec2bin(DPCCH_SLOT10,true);
		bvec DPCCH11=dec2bin(DPCCH_SLOT11,true);
		bvec DPCCH12=dec2bin(DPCCH_SLOT12,true);
		bvec DPCCH13=dec2bin(DPCCH_SLOT13,true);
		bvec DPCCH14=dec2bin(DPCCH_SLOT14,true);
		
		DPCCH.set_length(DPCCH_NBits,false);
		bvec conDPCCH0=concat(DPCCH0,DPCCH1,DPCCH2,DPCCH3,DPCCH4);
		bvec conDPCCH1=concat(DPCCH5,DPCCH6,DPCCH7,DPCCH8,DPCCH9);
		bvec conDPCCH2=concat(DPCCH10,DPCCH11,DPCCH12,DPCCH13,DPCCH14);
		DPCCH=concat(conDPCCH0,conDPCCH1,conDPCCH2);

		gold.generate();


		
	}
Esempio n. 3
0
bool Reed_Solomon::decode(const bvec &coded_bits, const ivec &erasure_positions, bvec &decoded_message, bvec &cw_isvalid)
{
  bool decoderfailure, no_dec_failure;
  int j, i, kk, l, L, foundzeros, iterations = floor_i(static_cast<double>(coded_bits.length()) / (n * m));
  bvec mbit(m * k);
  decoded_message.set_size(iterations * k * m, false);
  cw_isvalid.set_length(iterations);

  GFX rx(q, n - 1), cx(q, n - 1), mx(q, k - 1), ex(q, n - 1), S(q, 2 * t), Xi(q, 2 * t), Gamma(q), Lambda(q),
      Psiprime(q), OldLambda(q), T(q), Omega(q);
  GFX dummy(q), One(q, (char*)"0"), Omegatemp(q);
  GF delta(q), tempsum(q), rtemp(q), temp(q), Xk(q), Xkinv(q);
  ivec errorpos;

  if ( erasure_positions.length() ) {
    it_assert(max(erasure_positions) < iterations*n, "Reed_Solomon::decode: erasure position is invalid.");
  }
  
  no_dec_failure = true;
  for (i = 0; i < iterations; i++) {
    decoderfailure = false;
    //Fix the received polynomial r(x)
    for (j = 0; j < n; j++) {
      rtemp.set(q, coded_bits.mid(i * n * m + j * m, m));
      rx[j] = rtemp;
    }
    // Fix the Erasure polynomial Gamma(x)
    // and replace erased coordinates with zeros
    rtemp.set(q, -1);
    ivec alphapow = - ones_i(2);
    Gamma = One;
    for (j = 0; j < erasure_positions.length(); j++) {
      rx[erasure_positions(j)] = rtemp;
      alphapow(1) = erasure_positions(j);
      Gamma *= (One - GFX(q, alphapow));
    }
    //Fix the syndrome polynomial S(x).
    S.clear();
    for (j = 1; j <= 2 * t; j++) {
      S[j] = rx(GF(q, b + j - 1));
    }
    // calculate the modified syndrome polynomial Xi(x) = Gamma * (1+S) - 1
    Xi = Gamma * (One + S) - One;
    // Apply Berlekam-Massey algorithm
    if (Xi.get_true_degree() >= 1) { //Errors in the received word
      // Iterate to find Lambda(x), which hold all error locations
      kk = 0;
      Lambda = One;
      L = 0;
      T = GFX(q, (char*)"-1 0");
      while (kk < 2 * t) {
        kk = kk + 1;
        tempsum = GF(q, -1);
        for (l = 1; l <= L; l++) {
          tempsum += Lambda[l] * Xi[kk - l];
        }
        delta = Xi[kk] - tempsum;
        if (delta != GF(q, -1)) {
          OldLambda = Lambda;
          Lambda -= delta * T;
          if (2 * L < kk) {
            L = kk - L;
            T = OldLambda / delta;
          }
        }
        T = GFX(q, (char*)"-1 0") * T;
      }
      // Find the zeros to Lambda(x)
      errorpos.set_size(Lambda.get_true_degree());
      foundzeros = 0;
      for (j = q - 2; j >= 0; j--) {
        if (Lambda(GF(q, j)) == GF(q, -1)) {
          errorpos(foundzeros) = (n - j) % n;
          foundzeros += 1;
          if (foundzeros >= Lambda.get_true_degree()) {
            break;
          }
        }
      }
      if (foundzeros != Lambda.get_true_degree()) {
        decoderfailure = true;
      }
      else { // Forney algorithm...
        //Compute Omega(x) using the key equation for RS-decoding
        Omega.set_degree(2 * t);
        Omegatemp = Lambda * (One + Xi);
        for (j = 0; j <= 2 * t; j++) {
          Omega[j] = Omegatemp[j];
        }
        //Find the error/erasure magnitude polynomial by treating them the same
        Psiprime = formal_derivate(Lambda*Gamma);
        errorpos = concat(errorpos, erasure_positions);
        ex.clear();
        for (j = 0; j < errorpos.length(); j++) {
          Xk = GF(q, errorpos(j));
          Xkinv = GF(q, 0) / Xk;
          // we calculate ex = - error polynomial, in order to avoid the 
          // subtraction when recunstructing the corrected codeword
          ex[errorpos(j)] = (Xk * Omega(Xkinv)) / Psiprime(Xkinv);
          if (b != 1) { // non-narrow-sense code needs corrected error magnitudes
            int correction_exp = ( errorpos(j)*(1-b) ) % n;
            ex[errorpos(j)] *= GF(q, correction_exp + ( (correction_exp < 0) ? n : 0 ));
          }
        }
        //Reconstruct the corrected codeword.
        // instead of subtracting the error/erasures, we calculated 
        // the negative error with 'ex' above
        cx = rx + ex;
        //Code word validation
        S.clear();
        for (j = 1; j <= 2 * t; j++) {
          S[j] = cx(GF(q, b + j - 1));
        }
        if (S.get_true_degree() >= 1) {
          decoderfailure = true;
        }
      }
    }
    else {
      cx = rx;
      decoderfailure = false;
    }
    //Find the message polynomial
    mbit.clear();
    if (decoderfailure == false) {
      if (cx.get_true_degree() >= 1) { // A nonzero codeword was transmitted
        if (systematic) {
          for (j = 0; j < k; j++) {
            mx[j] = cx[j];
          }
        }
        else {
          mx = divgfx(cx, g);
        }
        for (j = 0; j <= mx.get_true_degree(); j++) {
          mbit.replace_mid(j * m, mx[j].get_vectorspace());
        }
      }
    }
    else { //Decoder failure.
      // for a systematic code it is better to extract the undecoded message
      // from the received code word, i.e. obtaining a bit error
      // prob. p_b << 1/2, than setting all-zero (p_b = 1/2)
      if (systematic) {
        mbit = coded_bits.mid(i * n * m, k * m);
      }
      else {
        mbit = zeros_b(k);
      }
      no_dec_failure = false;
    }
    decoded_message.replace_mid(i * m * k, mbit);
    cw_isvalid(i) = (!decoderfailure);
  }
  return no_dec_failure;
}