How to Implement Network Carrier Aggregation in NS2
To implement the network Carrier aggregation is a method that used in wireless communication, especially in LTE-Advanced (LTE-A) and 5G systems, to combine several frequency bands (carriers) to maximise the bandwidth and enhance the data rates. Executing the network carrier aggregation within the simulation platform NS2 needs replicating the impact of combining numerous carriers for a mobile or wireless network.
Since, NS2 doesn’t natively support furthered features such as carrier aggregation directly out of the box. But, we can replicate the impacts of carrier aggregation by combining various wireless channels and also handling traffic over these channels. The idea is to make numerous logical channels (representing different carriers), and mimic the combined bandwidth over them.
Here’s a step-by-step guide on how to implement carrier aggregation in NS2:
Step-by-Step Implementation:
- Understand the Structure of Carrier Aggregation:
The carrier aggregation includes aggregating several component carriers (CCs) to attain higher bandwidth. Every single carrier can have various frequency bands and bandwidths. The aggregation can be:
- Intra-band contiguous: Carriers are from the similar band and are adjacent.
- Intra-band non-contiguous: Carriers are from the identical band however are non-adjacent.
- Inter-band non-contiguous: Carriers are from various bands.
- Simulating Multiple Channels in NS2:
In the simulation NS2, each carrier can denote as a distinct wireless channel. To mimic carrier aggregation, we require to describe numerous wireless channels and allocate nodes to transform traffic over these channels.
- Configure the Environment for Carrier Aggregation:
Primarily, describe multiple wireless channels in the simulation environment. It can be done by set up various wireless channels with single frequencies (or logical separation).
# Simulator instance
set ns [new Simulator]
# Define two separate wireless channels (representing two carriers)
set channel1 [new Channel/WirelessChannel]
set channel2 [new Channel/WirelessChannel]
# Set up other necessary components (e.g., Propagation, Antenna)
set prop [new Propagation/TwoRayGround]
set netif [new Phy/WirelessPhy]
set mac [new Mac/802_11]
set ll [new LL]
set ifq [new Queue/DropTail/PriQueue]
set ant [new Antenna/OmniAntenna]
- Create Nodes and Attach Them to Channels:
Every single mobile node should be capable to transfer and receive data across several channels. It replicates the impact of having numerous component carriers aggregated together.
Below is a how to setup a node to be associated with various channels:
# Configure node settings for mobile nodes on multiple channels
$ns node-config -adhocRouting AODV \
-llType $ll \
-macType $mac \
-ifqType $ifq \
-ifqLen 50 \
-antType $ant \
-propType $prop \
-phyType $netif \
-channelType $channel1
# Create node on channel 1
set node1 [$ns node]
# Change channel for carrier aggregation and create node on channel 2
$ns node-config -channelType $channel2
set node2 [$ns node]
- Simulating Aggregated Bandwidth:
To mimic the carrier aggregation, each node can transfer traffic over numerous channels. We can emulate this by having various traffic generators (CBR or FTP) signifying data transmitted over multiple component carriers.
For example, use UDP for traffic simulation over various channels.
# Create UDP traffic generator for carrier 1
set udp1 [new Agent/UDP]
set cbr1 [new Application/Traffic/CBR]
$cbr1 set packetSize_ 1000
$cbr1 set interval_ 0.005 ; # Adjust for bandwidth
$cbr1 attach-agent $udp1
$ns attach-agent $node1 $udp1
# Create UDP traffic generator for carrier 2
set udp2 [new Agent/UDP]
set cbr2 [new Application/Traffic/CBR]
$cbr2 set packetSize_ 1000
$cbr2 set interval_ 0.005 ; # Adjust for bandwidth
$cbr2 attach-agent $udp2
$ns attach-agent $node2 $udp2
# Create sink nodes to receive the traffic
set null1 [new Agent/Null]
set null2 [new Agent/Null]
$ns attach-agent $node1 $null1
$ns attach-agent $node2 $null2
- Assign Traffic Flows Over Multiple Channels:
To simulate the performance of carrier aggregation, we can setup the traffic to be divide among the two (or more) channels. This replicates the distribution of data over several component carriers in the real LTE-A or 5G network.
Example of traffic over multiple carriers:
# Send traffic over channel 1
$ns connect $udp1 $null1
$ns at 1.0 “$cbr1 start”
# Send traffic over channel 2
$ns connect $udp2 $null2
$ns at 1.0 “$cbr2 start”
- Simulate the Behavior of Carrier Aggregation:
In the simulation, you’ll need to account for how much data can be sent over both channels. For this, you can monitor the combined throughput, delay, and packet delivery rates across both carriers (channels).
Carrier aggregation improves the overall throughput, so you should simulate this by ensuring that both channels contribute to the total data rate.
- Add Network Performance Monitoring:
It’s significant to observe the network performance parameters like throughput, packet loss, and latency. It can be completed by allowing trace files in NS2 to estimate the traffic over each channel.
Example:
# Trace setup
set tracefile [open “tracefile.tr” w]
$ns trace-all $tracefile
- Run the Simulation:
Run the simulation for an exact time and gather the outcomes. Make certain that both channels are donating to the overall throughput.
Example:
# Define simulation end time
$ns at 10.0 “finish”
proc finish {} {
global ns tracefile
$ns flush-trace
close $tracefile
exit 0
}
# Run the simulation
$ns run
- Post-Simulation Analysis:
Estimate the trace files, after the simulation that to measure how much traffic was carried across each channel and how much bandwidth was combined. These tools such as XGraph can be used to plot performance metrics like throughput and delay.
- Optional: Enhance the Model with Dynamic Aggregation:
We can further optimize this simulation by actively modifying in which the channels are used by each node rely on the network conditions, same to how real-world systems switch among the obtainable component carriers.
- Consider Extensions or Moving to NS3:
If we require additional furthered features and more exact LTE/5G modeling, deliberate moving to NS3 that has better support for modern wireless technologies such as LTE and 5G, with carrier aggregation. There are LTE modules obtainable within NS3, which natively support carrier aggregation, containing the spectrum modeling and also radio resource management.
At the end, we guided you on how to execute and simulate the Network Carrier Aggregation with their significant details through methodical procedure in NS2. We will also offer more precise details about this topic in various materials.
Ns2project.com is here to be your go-to partner for guidance on implementing Network Carrier Aggregation using ns2tool. Our developers are ready to help you brainstorm the best thesis ideas and topics that fit your requirements where we provide project performance analysis support.