How to Calculate Network SNR and SINR in Ns3

To calculate the Signal-to-Noise Ratio (SNR) and Signal-to-Interference-plus-Noise Ratio (SINR) in ns3, we can use the built-in tracing capabilities. The metrics given in the simulator mainly used for evaluating the performance and quality of wireless communication links. While, simulating the built-in tracing capabilities present in the simulator will capture the metrics. The following instructions will guide how to calculate network SNR and SINR in ns3.

Step-by-Step Guide to Calculate Network SNR and SINR in ns3

1. Set Up the Simulation Environment:
   • Make sure ns3 is Installed and setted up correctly.
   • Include necessary modules for the simulation (e.g., LTE, WiFi, Internet, Mobility).
2. Create Network Topology:
   • Define nodes for the base stations (eNodeBs), access points (APs), and user equipment (UEs).
   • Set up the wireless network with appropriate configurations.
3. Configure Applications:
   • Install traffic generating applications (e.g., UDP, TCP) on the UEs.
4. Enable Tracing and Metrics Collection:
   • Enable tracing to capture relevant metrics such as SNR and SINR.
5. Run the Simulation:
   • Execute the simulation and collect the trace data.
6. Analyze the Results:
   • Post-process the trace data to calculate and log the SNR and SINR values.

Example Code Snippet for LTE Network

Here’s an example of how to set up an LTE network, generate traffic, and capture SNR and SINR values in ns3:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

#include “ns3/point-to-point-module.h”

#include “ns3/applications-module.h”

#include “ns3/lte-module.h”

#include “ns3/epc-helper.h”

#include “ns3/mobility-module.h”

#include “ns3/config-store.h”

using namespace ns3;

NS_LOG_COMPONENT_DEFINE (“LteSnrSinrExample”);

void PhyRxStats (Ptr<OutputStreamWrapper> stream, std::string context, uint16_t cellId, uint16_t rnti, double snr)

{

*stream->GetStream () << Simulator::Now ().GetSeconds () << “\t” << cellId << “\t” << rnti << “\t” << snr << std::endl;

}

int main (int argc, char *argv[])

{

// Set up logging

LogComponentEnable (“LteHelper”, LOG_LEVEL_INFO);

// Create LTE network nodes

NodeContainer ueNodes;

NodeContainer enbNodes;

ueNodes.Create (10);

enbNodes.Create (3);

// Install Mobility model

MobilityHelper mobility;

mobility.SetMobilityModel (“ns3::ConstantPositionMobilityModel”);

mobility.Install (enbNodes);

mobility.SetPositionAllocator (“ns3::GridPositionAllocator”,

“MinX”, DoubleValue (0.0),

“MinY”, DoubleValue (0.0),

“DeltaX”, DoubleValue (50.0),

“DeltaY”, DoubleValue (50.0),

“GridWidth”, UintegerValue (3),

“LayoutType”, StringValue (“RowFirst”));

mobility.Install (ueNodes);

// Create LTE helper and EPC helper

Ptr<LteHelper> lteHelper = CreateObject<LteHelper> ();

Ptr<PointToPointEpcHelper> epcHelper = CreateObject<PointToPointEpcHelper> ();

lteHelper->SetEpcHelper (epcHelper);

// Install LTE devices to the nodes

NetDeviceContainer enbLteDevs = lteHelper->InstallEnbDevice (enbNodes);

NetDeviceContainer ueLteDevs = lteHelper->InstallUeDevice (ueNodes);

// Install Internet stack on UEs

InternetStackHelper internet;

internet.Install (ueNodes);

 

// Assign IP addresses to UEs

Ipv4InterfaceContainer ueIpIface;

ueIpIface = epcHelper->AssignUeIpv4Address (NetDeviceContainer (ueLteDevs));

// Attach UEs to eNodeBs

for (uint32_t i = 0; i < ueNodes.GetN (); ++i)

{

lteHelper->Attach (ueLteDevs.Get (i), enbLteDevs.Get (i % enbNodes.GetN ()));

}

// Install and start applications on UEs and remote host

uint16_t dlPort = 1234;

ApplicationContainer clientApps;

ApplicationContainer serverApps;

for (uint32_t i = 0; i < ueNodes.GetN (); ++i)

{

UdpServerHelper myServer (dlPort);

serverApps.Add (myServer.Install (ueNodes.Get (i)));

UdpClientHelper myClient (ueIpIface.GetAddress (i), dlPort);

myClient.SetAttribute (“MaxPackets”, UintegerValue (1000));

myClient.SetAttribute (“Interval”, TimeValue (MilliSeconds (100)));

myClient.SetAttribute (“PacketSize”, UintegerValue (1024));

clientApps.Add (myClient.Install (ueNodes.Get (i)));

}

serverApps.Start (Seconds (1.0));

serverApps.Stop (Seconds (10.0));

clientApps.Start (Seconds (2.0));

clientApps.Stop (Seconds (10.0));

// Create output stream for logging SNR and SINR

AsciiTraceHelper ascii;

Ptr<OutputStreamWrapper> stream = ascii.CreateFileStream (“snr-sinr-trace.txt”);

*stream->GetStream () << “Time(s)\tCellId\tRNTI\tSNR(dB)\n”;

// Connect to trace sources

Config::Connect (“/NodeList/*/DeviceList/*/LteUePhy/ReportCurrentCellRsrpSinr”,

MakeBoundCallback (&PhyRxStats, stream));

// Run the simulation

Simulator::Stop (Seconds (11.0));

Simulator::Run ();

// Clean up

Simulator::Destroy ();

return 0;

}

Explanation:

1. Setup Logging:
   • Enable logging for the LTE components to track their activities.
2. Create Nodes and Network:
   • Create nodes representing UEs and eNodeBs.
   • Configure mobility models for UEs and eNodeBs.
3. Install LTE and EPC Helper:
   • Create and configure LTE and EPC helpers.
   • Install LTE devices on the UEs and eNodeBs.
4. Install Internet Stack:
   • Install the Internet stack on UEs.
   • Assign IP addresses to the UEs.
5. Attach UEs to eNodeBs:
   • Attach each UE to an eNodeB. Here, a round-robin attachment is used for simplicity.
6. Install Applications:
   • Install UDP server applications on the UEs.
   • Install UDP client applications on the UEs, sending traffic to the server.
7. Connect to Trace Sources:
   • Create an output stream for logging SNR and SINR values.
   • Connect to the trace source for reporting SNR and SINR.
8. Run Simulation:
   • Run the simulation for the specified duration.
9. Analyze the Results:
   • The SNR and SINR values for each UE are logged along with the simulation time, cell ID, and RNTI.

Analyzing the Results:

• SNR and SINR:
  • The SNR and SINR values for each UE are logged periodically during the simulation.
  • These metrics provide an indication of the signal quality and interference levels in the network.

The above steps clearly explained that how to implement network SNR and SINR in ns3 using the traffic generation applications like UDP, TCP on the UEs and analyzing the results using post-processing the data for calculating and logging the SNR and SINR values.Signal-to-Noise Ratio (SNR) and Signal-to-Interference-plus-Noise Ratio (SINR) in ns3tool , project performance will be assisted by us.