How to Implement Network Energy Harvesting URLLC in NS2

To implement the network energy harvesting with URLLC (Ultra-Reliable Low-Latency Communication) within NS2 (Network Simulator 2) that includes combining two advanced concepts. They are:

  1. Energy Harvesting: Wireless sensor nodes harvest energy from the environmental sources such as solar, RF, or vibrations to power their communications.
  2. URLLC: It is a vital 5G feature, which make sure that ultra-reliable communication with too low latency, and it is crucial for applications like autonomous vehicles, industrial automation, and remote surgery.

Key Objectives:

  1. Energy Harvesting: These nodes can be collected and stored the energy from renewable sources over time, and they utilize this energy to execute their tasks such as sending or receiving packets.
  2. URLLC: Communication should meet strict requirements of the reliability and latency that encompasses managing the packet scheduling and transmission priorities according to the obtainable energy.

Step-by-Step Guide to Implement Network Energy Harvesting URLLC in NS2

  1. Extend NS2 to Support Energy Harvesting

The simulation environment NS2 is already has a simple EnergyModel class that replicates the energy consumption. But, energy harvesting functionality requires to be added, and also permitting nodes to recharge rely on the external energy sources. We will also want to account for the various energy consumption levels for URLLC communications in which demand low latency and high reliability.

Example C++ Code for Energy Harvesting Model:

Expand the EnergyModel class to replicate the energy harvesting in the nodes.

class EnergyHarvestingModel : public EnergyModel {

public:

EnergyHarvestingModel();

void updateEnergyHarvested(double time);  // Update energy harvested over time

void consumeEnergyForURLLC(double amount);  // Consume energy based on URLLC transmission requirements

protected:

double harvestedEnergyRate;  // Energy harvested per second (e.g., from solar)

double maxEnergyCapacity;    // Maximum energy that the node can store

double currentEnergy;        // Current energy level of the node

};

// Constructor to initialize the energy model

EnergyHarvestingModel::EnergyHarvestingModel() : EnergyModel(), harvestedEnergyRate(0.05), maxEnergyCapacity(100.0), currentEnergy(50.0) {

}

// Update the amount of energy harvested over a time period

void EnergyHarvestingModel::updateEnergyHarvested(double time) {

double energyHarvested = harvestedEnergyRate * time;

currentEnergy += energyHarvested;

if (currentEnergy > maxEnergyCapacity) {

currentEnergy = maxEnergyCapacity;  // Ensure we don’t exceed the energy capacity

}

}

// Consume energy during URLLC transmission (URLLC requires more energy due to strict latency/reliability)

void EnergyHarvestingModel::consumeEnergyForURLLC(double amount) {

currentEnergy -= amount;

if (currentEnergy < 0) {

currentEnergy = 0;  // Ensure the energy doesn’t drop below zero

}

}

  1. URLLC Traffic Model

To mimic URLLC traffic, we want to configure a special class of traffic which has strict reliability and latency requirements. It can be completed by prioritizing packet transmission, minimising delay in the MAC layer, and also make sure energy resources are assigned well to meet URLLC’s strict QoS (Quality of Service).

Define URLLC Traffic Requirements:

  • Latency: Place the strict time constraints for packet delivery.
  • Reliability: Make sure high packet delivery ratios, even under constrained energy availability.

Example URLLC Traffic in C++:

class URLLCTraffic {

public:

URLLCTraffic();

void sendURLLCPacket();      // Send a URLLC packet

bool checkLatency(double latency);  // Check if packet meets the latency requirement

protected:

double maxAllowedLatency;  // Maximum latency allowed for URLLC

double requiredReliability;  // Required packet delivery success rate

};

// Constructor for URLLC traffic model

URLLCTraffic::URLLCTraffic() : maxAllowedLatency(0.01), requiredReliability(0.999) {  // Example: 10 ms max latency

}

// Send a URLLC packet with strict requirements

void URLLCTraffic::sendURLLCPacket() {

if (checkEnergyAvailable()) {

// Use available energy to send URLLC packet

consumeEnergyForURLLC(energyRequiredForURLLC);

} else {

// Not enough energy to send the URLLC packet, drop the packet

dropPacket();

}

}

// Check if packet meets the latency requirement

bool URLLCTraffic::checkLatency(double latency) {

return latency <= maxAllowedLatency;

}

  1. Modify the MAC Layer to Prioritize URLLC Packets

In the MAC layer that execute the packet prioritization. URLLC packets should transfer immediately, including higher priority over other kinds of traffic, and make sure low latency and high reliability.

Prioritize URLLC Traffic:

Expand the MAC layer to process URLLC packets first, verifying the energy availability and scheduling the transmissions consequently.

class URLLCMac : public Mac {

public:

URLLCMac();

void transmitPacket(Packet *p);

void scheduleURLLCTransmission(Packet *p);  // Prioritize URLLC transmission

protected:

bool hasEnergyForURLLC;  // Check if enough energy is available for URLLC

};

// Constructor

URLLCMac::URLLCMac() : Mac(), hasEnergyForURLLC(true) {}

// Transmit a packet, prioritizing URLLC

void URLLCMac::transmitPacket(Packet *p) {

if (isURLLCPacket(p)) {

if (hasEnergyForURLLC) {

scheduleURLLCTransmission(p);  // Schedule transmission if energy is available

} else {

dropPacket(p);  // Drop packet if insufficient energy for URLLC

}

} else {

Mac::transmitPacket(p);  // Handle other types of traffic normally

}

}

// Prioritize URLLC transmission

void URLLCMac::scheduleURLLCTransmission(Packet *p) {

// Immediately schedule transmission

send(p);

}

  1. Energy-aware Scheduling for URLLC

To extend the energy efficiency during the meeting URLLC requirements, nodes are require to actively modify their scheduling according to both energy availability and the priority of the traffic.

We execute a basic energy-aware scheduling algorithm, which provides priority to URLLC packets while energy is available, and defers other kinds of traffic to periods during energy is scarce.

  1. Simulate Energy Harvesting and URLLC in NS2

When the energy harvesting model and URLLC traffic are incorporated into the physical layers, and MAC, we can replicate the network within the NS2. We will want to set up the nodes to harvest energy over time and make sure that URLLC packets are transferred with strict latency and reliability constraints.

Example Tcl Script for Energy Harvesting and URLLC:

# Create a simulator instance

set ns [new Simulator]

# Create nodes

set node1 [$ns node]

set node2 [$ns node]

# Attach energy models (with energy harvesting)

set energyModel1 [new EnergyHarvestingModel]

set energyModel2 [new EnergyHarvestingModel]

$node1 set energyModel_ $energyModel1

$node2 set energyModel_ $energyModel2

# Set up MAC layer for URLLC

$node1 set mac_ [new Mac/URLLCMac]

$node2 set mac_ [new Mac/URLLCMac]

# Define URLLC traffic sources

set urlAgent1 [new Agent/URLLC]

set urlAgent2 [new Agent/URLLC]

$ns attach-agent $node1 $urlAgent1

$ns attach-agent $node2 $urlAgent2

# Set up traffic sources (URLLC traffic)

set urlcbr [new Application/Traffic/CBR]

$urlcbr set packetSize_ 512

$urlcbr set interval_ 0.005  ;# High-frequency traffic for URLLC

$urlcbr attach-agent $urlAgent1

# Start the simulation

$ns at 1.0 “$urlcbr start”

# Run the simulation

$ns run

  1. Evaluate Network Performance

When the simulation is done, compute the performance depends on the vital metrics like:

  • Energy Efficiency: Calculate how much energy is harvested and consumed by every node.
  • Latency: Make sure that URLLC packets are meet the needed low-latency constraints.
  • Reliability: Estimate the packet delivery ratio (PDR) for the URLLC traffic.
  • Throughput: Investigate how much data is effectively transmitted.

As above details, we delivered the execution methods with some instances regarding to implement and evaluate the Network Energy Harvesting URLLC in the simulation tool NS2. Also we will be offered more informations in another materials. Contact ns2project.com for customized implementation assistance with Network Energy Harvesting URLLC in NS2guidance and project ideas. Stay in touch with us to receive the finest implementation help and outcomes. We work on network energy harvesting with URLLC (Ultra-Reliable Low-Latency Communication) in NS2 (Network Simulator 2) for your applications.