How to Implement Cellular Topology in ns3

To implement the cellular topology in ns3 has to create in structured manner by setup the base station (eNodeB) and multiple user equipment (UE) nodes. LTE module is used in ns3 for the cellular purpose.

Here, we provide the procedure on how to simulate the cellular topology in ns3:

Step-by-Step Implementation

Step 1: Install ns3

• Make sure ns3 is installed in the computer.

Step 2: Create a New Simulation Script

• Create a new C++ script for your simulation.

Step 3: Include Necessary Headers

• In your script, include the necessary ns3 headers:

#include “ns3/core-module.h”

#include “ns3/network-module.h”

#include “ns3/internet-module.h”

#include “ns3/applications-module.h”

#include “ns3/mobility-module.h”

#include “ns3/lte-module.h”

#include “ns3/config-store.h”

Step 4: Set Up the Cellular Topology

Now we are going to see how to set up the basic cellular topology with one eNodeB and multiple UEs:

using namespace ns3;

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

{

// Configure command line parameters

CommandLine cmd;

cmd.Parse (argc, argv);

// Create nodes: one eNodeB and several UEs

NodeContainer ueNodes;

ueNodes.Create (3); // Create 3 UEs

NodeContainer enbNodes;

enbNodes.Create (1); // Create 1 eNodeB

// Configure Mobility

MobilityHelper mobility;

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

// Set eNodeB position

Ptr<ListPositionAllocator> positionAlloc = CreateObject<ListPositionAllocator> ();

positionAlloc->Add (Vector (0.0, 0.0, 0.0)); // eNodeB at origin

mobility.SetPositionAllocator (positionAlloc);

mobility.Install (enbNodes);

// Set UE positions

Ptr<GridPositionAllocator> positionAllocUe = CreateObject<GridPositionAllocator> ();

positionAllocUe->SetMinX (20.0);

positionAllocUe->SetMinY (20.0);

positionAllocUe->SetDeltaX (20.0);

positionAllocUe->SetDeltaY (20.0);

positionAllocUe->SetGridWidth (2);

positionAllocUe->SetLayoutType (GridPositionAllocator::ROW_FIRST);

mobility.SetPositionAllocator (positionAllocUe);

mobility.Install (ueNodes);

// Install LTE Devices to the nodes

NetDeviceContainer enbLteDevs;

NetDeviceContainer ueLteDevs;

LteHelper lteHelper;

enbLteDevs = lteHelper.InstallEnbDevice (enbNodes);

ueLteDevs = lteHelper.InstallUeDevice (ueNodes);

// Install the IP stack on the UEs

InternetStackHelper internet;

internet.Install (ueNodes);

// Assign IP addresses to UEs

Ipv4InterfaceContainer ueIpIface;

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

// Attach UEs to the eNodeB

lteHelper.Attach (ueLteDevs, enbLteDevs.Get (0));

// Set up applications

uint16_t dlPort = 1234;

ApplicationContainer clientApps;

ApplicationContainer serverApps;

UdpClientHelper dlClient (ueIpIface.GetAddress (0), dlPort);

dlClient.SetAttribute (“Interval”, TimeValue (MilliSeconds (10)));

dlClient.SetAttribute (“MaxPackets”, UintegerValue (1000000));

clientApps.Add (dlClient.Install (remoteHost));

clientApps.Start (Seconds (0.01));

clientApps.Stop (Seconds (10.0));

UdpServerHelper dlServer (dlPort);

serverApps.Add (dlServer.Install (ueNodes.Get (0)));

serverApps.Start (Seconds (0.01));

serverApps.Stop (Seconds (10.0));

// Run simulation

Simulator::Stop (Seconds (10.0));

Simulator::Run ();

Simulator::Destroy ();

return 0;

}

Step 5: Build and Run the Simulation

1. Save the script as cellular-topology.cc.
2. Build the script using waf:

./waf configure –enable-examples

./waf build

1. Run the simulation:

./waf –run scratch/cellular-topology

Explanation of the Script

• Node Creation: Creates one eNodeB and three UEs.
• Mobility Model: Sets the mobility model to ConstantPositionMobilityModel and places the eNodeB at the origin and UEs in a grid pattern.
• LTE Devices: Installs LTE devices on the eNodeB and UEs.
• Internet Stack: Installs the IP stack on the UEs and assigns IP addresses.
• Applications: Sets up a UDP client-server application to demonstrate downlink traffic.

Here, we have implemented the simulation for Cellular Topology in ns3 that has includes the headers, make the topology and run the simulation to show the traffic by using ns3 tool. We will also outline the steps involved in Cellular Topology in different simulation.

Provide us with all the necessary details of your parameters so that we can offer you further assistance with implantation related to Cellular Topology in ns3.