How to Implement Satellite Communication in OMNeT++

To implement the satellite communication in OMNeT++ requires an environment that has satellite nodes, ground stations, and communication links among them. Support satellite communication functionalities by extending the INET framework. Here’s a step-by-step guide to help you get started with a basic satellite communication simulation in OMNeT++ using the INET framework.

Step-by-Step Implementation:

Step 1: Install OMNeT++ and INET Framework

1. Download OMNeT++:
   • Download the latest version of OMNeT++.
2. Install OMNeT++:
   • Follow the installation instructions while installing.
3. Download and Install INET Framework:
   • The INET framework offers models for internet protocols and is often used with OMNeT++.
   • Install the INET framework on the system.

Step 2: Set Up Your Project

1. Create a New OMNeT++ Project:
   • Open the OMNeT++ IDE.
   • Go to File -> New -> OMNeT++ Project.
   • Enter a project name and pick the appropriate options.
2. Set Up Directory Structure:
   • Ensure project has the important folders like src for source files and simulations for NED files and configuration.
3. Add INET to Your Project:
   • Right-click on project in the Project Explorer.
   • Select Properties -> Project References.
   • Check the box for INET.

Step 3: Define Satellite Network Models Using NED

1. Create NED Files:
   • Create a new NED file (for instance: SatelliteNetwork.ned) in src directory,
   • Determine the network topology in the NED file. Here’s a simple example:

package satellite;

import inet.node.inet.StandardHost;

import inet.node.inet.Router;

import inet.mobility.single.ConstSpeedMobility;

import inet.physicallayer.common.packetlevel.RadioMedium;

network SatelliteNetwork

{

parameters:

int numSatellites = default(3);

int numGroundStations = default(2);

submodules:

radioMedium: RadioMedium {

@display(“p=100,100”);

}

groundStation[numGroundStations]: StandardHost {

@display(“p=200,300+100*i”);

}

satellite[numSatellites]: StandardHost {

@display(“p=400,100+100*i”);

mobility.typename = “ConstSpeedMobility”;

}

connections allowunconnected:

for i=0..numGroundStations-1 {

groundStation[i].wlan[0] <–> radioMedium <–> satellite[0].wlan[0];

}

for i=0..numSatellites-1 {

satellite[i].wlan[0] <–> radioMedium <–> satellite[(i+1) % numSatellites].wlan[0];

}

}

Step 4: Implement Satellite Communication Logic

1. Create C++ Modules for Satellite Communication:
   • We have to create new C++ classes (e.g., SatelliteTransmitter.cc and SatelliteReceiver.cc) in the src directory,.
   • Has the required OMNeT++ headers and define satellite communication logic.
2. Satellite Transmitter Implementation:

#include <omnetpp.h>

#include “inet/applications/base/ApplicationBase.h”

#include “inet/common/packet/Packet.h”

using namespace omnetpp;

using namespace inet;

class SatelliteTransmitter : public ApplicationBase

{

protected:

virtual void initialize(int stage) override;

virtual void handleMessageWhenUp(cMessage *msg) override;

void sendSatelliteMessage();

void handleSatelliteMessage(cPacket *pkt);

cMessage *sendEvent = nullptr;

};

Define_Module(SatelliteTransmitter);

void SatelliteTransmitter::initialize(int stage)

{

ApplicationBase::initialize(stage);

if (stage == INITSTAGE_LOCAL) {

sendEvent = new cMessage(“sendSatelliteMessage”);

scheduleAt(simTime() + par(“startTime”), sendEvent);

}

}

void SatelliteTransmitter::handleMessageWhenUp(cMessage *msg)

{

if (msg == sendEvent) {

sendSatelliteMessage();

scheduleAt(simTime() + par(“sendInterval”), sendEvent);

} else {

cPacket *pkt = check_and_cast<cPacket *>(msg);

handleSatelliteMessage(pkt);

}

}

void SatelliteTransmitter::sendSatelliteMessage()

{

// Create and send a satellite message to the next node

EV << “Sending satellite message” << endl;

Packet *pkt = new Packet(“SatelliteMessage”);

pkt->setByteLength(par(“messageSize”));

send(pkt, “lowerLayerOut”);

}

void SatelliteTransmitter::handleSatelliteMessage(cPacket *pkt)

{

// Handle received satellite message

EV << “Received satellite message: ” << pkt->getName() << endl;

delete pkt;

}

1. Satellite Receiver Implementation:

#include <omnetpp.h>

#include “inet/applications/base/ApplicationBase.h”

#include “inet/common/packet/Packet.h”

using namespace omnetpp;

using namespace inet;

class SatelliteReceiver : public ApplicationBase

{

protected:

virtual void initialize(int stage) override;

virtual void handleMessageWhenUp(cMessage *msg) override;

void handleSatelliteMessage(cPacket *pkt);

};

Define_Module(SatelliteReceiver);

void SatelliteReceiver::initialize(int stage)

{

ApplicationBase::initialize(stage);

}

void SatelliteReceiver::handleMessageWhenUp(cMessage *msg)

{

if (msg->isSelfMessage()) {

delete msg;

} else {

cPacket *pkt = check_and_cast<cPacket *>(msg);

handleSatelliteMessage(pkt);

}

}

void SatelliteReceiver::handleSatelliteMessage(cPacket *pkt)

{

// Handle received satellite message

EV << “Received satellite message: ” << pkt->getName() << endl;

delete pkt;

}

Step 5: Integrate Satellite Modules into Network Model

1. Modify NED File to Use Satellite Modules:
   • Update your NED file to use the custom satellite transmitter and receiver modules:

package satellite;

import inet.node.inet.StandardHost;

import inet.node.inet.Router;

import inet.mobility.single.ConstSpeedMobility;

import inet.physicallayer.contract.packetlevel.IRadioMedium;

import inet.physicallayer.common.packetlevel.RadioMedium;

network SatelliteNetwork

{

parameters:

int numSatellites = default(3);

int numGroundStations = default(2);

submodules:

radioMedium: RadioMedium {

@display(“p=100,100”);

}

groundStation[numGroundStations]: StandardHost {

@display(“p=200,300+100*i”);

@children:

wlan[0].radio.transmitter.typename = “SatelliteTransmitter”;

wlan[0].radio.receiver.typename = “SatelliteReceiver”;

}

satellite[numSatellites]: StandardHost {

@display(“p=400,100+100*i”);

mobility.typename = “ConstSpeedMobility”;

@children:

wlan[0].radio.transmitter.typename = “SatelliteTransmitter”;

wlan[0].radio.receiver.typename = “SatelliteReceiver”;

}

connections allowunconnected:

for i=0..numGroundStations-1 {

groundStation[i].wlan[0] <–> radioMedium <–> satellite[0].wlan[0];

}

for i=0..numSatellites-1 {

satellite[i].wlan[0] <–> radioMedium <–> satellite[(i+1) % numSatellites].wlan[0];

}

}

Step 6: Configure Simulation Parameters

1. Create omnetpp.ini:
   • Create an omnetpp.ini file inside the simulation directory.
   • Define simulation parameters like duration and network parameters:

[General]

network = SatelliteNetwork

sim-time-limit = 100s

# Mobility

**.satellite[*].mobility.speed = 7000mps

# Satellite transmitter and receiver parameters

**.groundStation[*].udpApp.startTime = uniform(0s, 10s)

**.groundStation[*].udpApp.sendInterval = exponential(1s)

**.groundStation[*].udpApp.messageSize = 256B

**.groundStation[*].udpApp.localPort = 1000

**.groundStation[*].udpApp.destPort = 2000

**.satellite[*].udpApp.localPort = 2000

Step 7: Build and Run the Simulation

1. Build the Project:
   • In the OMNeT++ IDE, right-click on your project and choose Build Project.
2. Run the Simulation:
   • Go to Run -> Run Configurations.
   • Set up a new run configuration for the project and run the simulation.

Step 8: Analyze Results

1. View Simulation Results:
   • Use OMNeT++’s tools to analyze the results, once the simulation ends.
   • Open the ANF (Analysis Framework) to visualize and interpret the data.

Finally, we successfully learned the needed information to use the Satellite Communication with the help of the above implementation guide and also provided the INET framework installation and how to extend them in this script using OMNeT++.

If you’re looking to implement satellite communication in OMNeT++, feel free to reach out to us. Our top developers can help you achieve the best simulation and project performance results. We specialize in the INET framework.