How to Implement Low earth orbit satellite in OMNeT++
To implement the Low Earth Orbit (LEO) Satellite Networks in OMNeT++, we have to simulate network of satellites in low earth orbit which interact with one another and also with ground station. These networks are used for global communication services, internet coverage and earth observation. Approach omnet-manual.com we offer best network performance analysis assistance. In the following, we deliver the step-by-step guide to implementing LEO satellite networks in OMNeT++.
Step-by-Step Implementation:
- Define the LEO Satellite Network Architecture
- Satellites: Indicates the LEO satellites orbiting the Earth and using inter-satellite links (ISLs) to communicate with each other and with ground stations.
- Ground Stations: Denotes the nodes on Earth that communicate with satellites.
- Inter-Satellite Links (ISLs): Signifies the optical or radio frequency communication links amongst satellites.
- Satellite-to-Ground Links: Represent the communication links amongst satellites and ground stations.
- Create OMNeT++ Modules for Satellites, Ground Stations, and Links
- Satellite Module: Indicates a satellite node capable of transmitting and receiving signals from other satellites and ground stations.
- Ground Station Module: Represents a ground station skilled of communicating with satellites.
- Link Modules (ISL and Ground Links): Simulate the communication links amongst satellites and amidst satellites and ground stations.
Example: Satellite Module
simple Satellite {
gates:
inout radioIn[4]; // For communication with other satellites (ISLs)
inout groundIn[2]; // For communication with ground stations
parameters:
double altitude @unit(“km”) = default(500); // Satellite altitude
double speed @unit(“km/s”) = default(7.8); // Orbital speed
@display(“i=device/satellite”);
}
Example: Ground Station Module
simple GroundStation {
gates:
inout groundOut; // For communication with satellites
parameters:
@display(“i=device/groundstation”);
}
Example: Inter-Satellite Link (ISL) Module
simple InterSatelliteLink {
parameters:
double distance @unit(“km”) = default(1000); // Distance between satellites
double dataRate @unit(“Gbps”) = default(10); // Data rate of the ISL
double latency @unit(“ms”) = default(5); // Latency for the signal to travel the distance
gates:
in linkIn; // Input from one satellite
out linkOut; // Output to another satellite
}
Example: Satellite-to-Ground Link Module
simple SatToGroundLink {
parameters:
double distance @unit(“km”) = default(500); // Distance from satellite to ground station
double dataRate @unit(“Gbps”) = default(10); // Data rate of the link
double latency @unit(“ms”) = default(2); // Latency for the signal to travel the distance
gates:
in linkIn; // Input from satellite
out linkOut; // Output to ground station
}
- Implement the Internal Logic of Each Component
- Satellite Logic: Manage the transmission and reception of signals from other satellites and ground stations. Also, handle the satellite’s movement in orbit.
- Ground Station Logic: Manage communication with satellites, containing sending and receiving data.
- Link Logic: Simulate the transmission of data over the links, including managing the latency and any signal attenuation.
Example: Satellite Logic in C++
#include <omnetpp.h>
class Satellite : public omnetpp::cSimpleModule {
protected:
virtual void handleMessage(omnetpp::cMessage *msg) override;
virtual void initialize() override;
void updatePosition(); // Method to update satellite position in orbit
double altitude;
double speed;
};
Define_Module(Satellite);
void Satellite::initialize() {
altitude = par(“altitude”);
speed = par(“speed”);
// Schedule the first position update
scheduleAt(simTime() + 1.0, new cMessage(“updatePosition”));
}
void Satellite::handleMessage(omnetpp::cMessage *msg) {
if (strcmp(msg->getName(), “updatePosition”) == 0) {
updatePosition();
scheduleAt(simTime() + 1.0, msg); // Schedule the next position update
} else if (strcmp(msg->getName(), “radioData”) == 0) {
// Handle data received from another satellite or ground station
send(msg, “radioIn$o”, 0); // Example: forward to the first ISL
} else {
// Handle other types of messages, if any
}
}
void Satellite::updatePosition() {
// Logic to update the satellite’s position based on orbital mechanics
// This could involve changing altitude, calculating new positions, etc.
EV << “Satellite position updated.\n”;
}
Example: Inter-Satellite Link Logic in C++
#include <omnetpp.h>
class InterSatelliteLink : public omnetpp::cSimpleModule {
protected:
virtual void handleMessage(omnetpp::cMessage *msg) override;
virtual void initialize() override;
double distance;
double dataRate;
double latency;
};
Define_Module(InterSatelliteLink);
void InterSatelliteLink::initialize() {
distance = par(“distance”);
dataRate = par(“dataRate”);
latency = par(“latency”);
}
void InterSatelliteLink::handleMessage(omnetpp::cMessage *msg) {
// Simulate transmission delay based on distance and latency
sendDelayed(msg, latency, “linkOut”);
}
- Integrate the Components in a NED File
- Define the network topology, linking satellites with ISLs and satellites to ground stations.
- Mention the locations and movements of the satellites to model the LEO network’s dynamics.
Example: LEO Satellite Network Topology in NED
network LEOSatelliteNetwork {
submodules:
satelliteA: Satellite {
parameters:
altitude = 500;
speed = 7.8;
}
satelliteB: Satellite {
parameters:
altitude = 500;
speed = 7.8;
}
groundStation: GroundStation;
linkAB: InterSatelliteLink {
parameters:
distance = 1000; // Distance between satelliteA and satelliteB
dataRate = 10Gbps;
latency = 5ms;
}
linkAG: SatToGroundLink {
parameters:
distance = 500; // Distance between satelliteA and groundStation
dataRate = 10Gbps;
latency = 2ms;
}
connections allowunconnected:
satelliteA.radioIn[0] –> linkAB.linkIn;
linkAB.linkOut –> satelliteB.radioIn[0];
satelliteA.groundIn[0] –> linkAG.linkIn;
linkAG.linkOut –> groundStation.groundOut;
}
- Simulate and Analyze the LEO Satellite Network
- Compile: Make certain that all modules are compiled in OMNeT++.
- Execute: Run the simulation to monitor how data is transmitted amongst satellites and amidst satellites and ground stations.
- Analyze: Use OMNeT++ tools to assess the network’s performance like latency, throughput, handover between satellites, and signal quality.
- Advanced Features
- Dynamic Topology: Execute logic to simulate the movement of satellites, varying distances and link latencies dynamically as the satellites orbit.
- Handover Management: Implement handover mechanisms as they a ground station switches its connection from one satellite to another.
- Routing Protocols: Implement routing algorithms for data transmission in the satellite network, consider the dynamic topology.
Example: Handover Management and Routing
- Handover Logic: Execute logic in the ground station to switch connections to the close satellite as the satellites move in their orbits.
- Routing Algorithm: Implement a routing algorithm in the satellites that dynamically fine-tuning routes based on the varying network topology.
Example: Handover Logic in Ground Station
void GroundStation::handleMessage(omnetpp::cMessage *msg) {
if (strcmp(msg->getName(), “handover”) == 0) {
// Logic to handover communication to a different satellite
int nearestSatelliteIndex = 0; // Example: choose the nearest satellite
send(msg, “groundOut”, nearestSatelliteIndex);
} else {
// Normal message handling
send(msg, “groundOut”);
}
}
In conclusion, it will help to improve your knowledge about Low Earth Orbit Satellite Networks using the OMNeT++ including how to define the architecture and how to execute the modules for elements in the network with examples. Nevertheless, we can also offer you anything regarding this topic.