5G LENA: Help about Different Values of SINR

[Angèle Hager Hafaiedh]

Hello everyone.

 I am building a SINR formula that emulates the ones logged by the simulator via DLDATASINR.

I work with parabolic Antennas (both UEs and Gnb) 

The values I received from my formulas is far from what was actually traced via DlDataSinr, even though I used the exact same values of parameters.

Here is my formula:

    double bandwidthHz ;//bandwidth
    double satAntennaGainDb ;
    double vsatAntennaGainDb;
     double sTxPower; Sat tx Power
    double frequencyHz ;
       double Brb=12*15e3;
    double Nrb=88;
    double pathloss=20*log10(d)+20*log10(frequencyHz)+20*log10(4*M_PI/3e8);//183.56db
  
    double T=290.0;
   
 

double c = 3e8;
double lambda = c / frequencyHz;

// Pathloss
double Lfs = pow((4*M_PI*d)/lambda, 2);

// Convert dBm to Watts
double PtxW = pow(10, (sTxPower - 30)/10.0);

// RB power
double PtxRb = PtxW / Brb;

// Gains (linear)
double Gt = pow(10, satAntennaGainDb/10.0);
double Gr = pow(10, vsatAntennaGainDb/10.0);

// Received power
double Pr = PtxRb *Gt / Lfs;

// Noise
double k = 1.38e-23;
double Noise = k * T *Brb*Nrb;

// SINR
double sinrLinear = Pr  / Noise;
double sinrDbCalcule = 10*log10(sinrLinear);

For context:

- I work with 5 users in around teh same position , therefore the same distance from the Satellite.

-I use Friis propag. loss model

-Numerology is 0

-Number of total Rbs is 88

-I use 3 bwps:

"//coté gnb

// BWP 0 - dl +ul
NrHelper::GetGnbPhy(gnbNetDev.Get(0), 0)
    ->SetAttribute("Pattern", StringValue("DL|UL|DL|UL|DL|UL|"));
//NrHelper::GetGnbPhy(gnbNetDev.Get(0), 0) ->SetAttribute("Numerology", UintegerValue(2));
//NrHelper::GetGnbPhy(gnbNetDev.Get(0), 0)->SetAttribute("TxPower", DoubleValue(4.0));

// BWP 1 - dl 
NrHelper::GetGnbPhy(gnbNetDev.Get(0), 1)
    ->SetAttribute("Pattern", StringValue("DL|DL|DL|DL|DL|DL|"));
    //NrHelper::GetGnbPhy(gnbNetDev.Get(0), 1)->SetAttribute("Numerology", UintegerValue(2));
    //NrHelper::GetGnbPhy(gnbNetDev.Get(0), 1)->SetAttribute("TxPower", DoubleValue(4.0));


// BWP 2 - ul
NrHelper::GetGnbPhy(gnbNetDev.Get(0), 2)
    ->SetAttribute("Pattern", StringValue("UL|UL|UL|UL|UL|UL|"));
    //NrHelper::GetGnbPhy(gnbNetDev.Get(0), 2)->SetAttribute("Numerology", UintegerValue(2));
//NrHelper::GetGnbPhy(gnbNetDev.Get(0), 2)->SetAttribute("TxPower", DoubleValue(4.0));

// ----- Link UL and DL BWPs -----


NrHelper::GetBwpManagerGnb(gnbNetDev.Get(0))->SetOutputLink(0, 0);
NrHelper::GetBwpManagerGnb(gnbNetDev.Get(0))->SetOutputLink(2, 1);



for (uint32_t i = 0; i < ueNetDev.GetN(); i++)
{
    NrHelper::GetBwpManagerUe(ueNetDev.Get(i))->SetOutputLink(0, 0);
    NrHelper::GetBwpManagerUe(ueNetDev.Get(i))->SetOutputLink(1, 2);
}

int64_t randomStream = 1;
    nrHelper->AssignStreams(gnbNetDev, randomStream);

    int64_t stream = 1;
    for (uint32_t i = 0; i < ueNetDev.GetN(); ++i)
{
    nrHelper->AssignStreams(ueNetDev.Get(i), stream);

}"

-I used the exact same parameters in my calculations as in NR

"double satTxPower =

        (sTxPower + 30) + (10 * std::log10(bandwidthHz / 1e6));

    for (uint32_t i = 0; i < gnbNetDev.GetN(); i++)
    {
        NrHelper::GetGnbPhy(gnbNetDev.Get(i), 0)->SetTxPower(sTxPower);
        // NrHelper::GetGnbPhy(gnbNetDev.Get(i), 0)->SetAttribute("TxAntennaGain",DoubleValue(49.22));
    }

    for (uint32_t i = 0; i < ueNetDev.GetN(); ++i)
    {
        NrHelper::GetUePhy(ueNetDev.Get(i), 1)->SetTxPower(groundTxPower);
        // NrHelper::GetUePhy(ueNetDev.Get(i), 0)->SetTxPower(groundTxPower);
       

    }"

-The NoiseFigure is set at 0 for both users and Gnb

-NumHarqprocess is set at 1

-I modified the GetGainDb in parabolic-antenna-model so that its calculation depends mostly on the central frequency.

May I know what other details did I miss? 

Thank you so much in advance