To simulate Cellular Networks using NS2, which is a challenging task since NS2 was primarily created for traditional IP-based networks (wired and wireless) such as TCP/IP, Wi-Fi, and MANETs. But, cellular network modules such as base stations, user equipment (UE), and core networks are not directly supported within NS2. To replicate cellular networks within NS2, we must prolong the simulator or utilize workarounds to model cellular network behaviour. If we want more detailed and exact cellular network simulations then the simulation platform NS3 is recommended because it has built-in support for cellular networks, particularly LTE.
phdprime.com will assist you with best simulation results, get the best project ideas tailored to your interest by working with us.
Steps to Simulate Cellular Network Projects in NS2
- Cellular Network Components in NS2
Cellular networks encompass numerous modules, containing:
- Base Station (BS): Same to eNodeB in LTE or cellular towers, BS manages communication among the mobile users (UE) and the core network.
- User Equipment (UE): Mobile devices, containing phones or IoT devices, which communicate with the base station.
- Core Network (EPC in LTE): Responsible for tasks such as session management, mobility, and data routing.
In NS2, we can simulate cellular network components utilizing a combination of wireless nodes and wireless channels.
- Cellular Network Simulation Workaround in NS2
We can be mimicked a basic cellular network within NS2 by treating base stations as fixed wireless nodes and mobile devices (UE) as wireless nodes, which communicate through base stations utilizing UDP or TCP traffic.
Example: Basic Cellular Network Simulation in NS2
# Create the NS2 simulator instance
set ns [new Simulator]
# Define a wireless channel for cellular communication
set cellular_channel [new Channel/WirelessChannel]
# Configure wireless nodes for the Base Station (BS) and User Equipment (UE)
$ns node-config -llType LL -macType Mac/802_11 -ifqType Queue/DropTail/PriQueue \
-ifqLen 50 -antType Antenna/OmniAntenna -propType Propagation/TwoRayGround \
-phyType Phy/WirelessPhy -channelType $cellular_channel
# Create a Base Station (BS)
set base_station [$ns node]
$base_station set X_ 100.0
$base_station set Y_ 100.0
$base_station set Z_ 0.0
# Create two User Equipment (UE) nodes
set UE1 [$ns node]
set UE2 [$ns node]
# Set positions for the UEs
$UE1 set X_ 50.0
$UE1 set Y_ 50.0
$UE1 set Z_ 0.0
$UE2 set X_ 150.0
$UE2 set Y_ 150.0
$UE2 set Z_ 0.0
# Attach UDP agents to UEs to send traffic to the Base Station
set udp1 [new Agent/UDP]
set udp2 [new Agent/UDP]
set null1 [new Agent/Null]
set null2 [new Agent/Null]
$ns attach-agent $UE1 $udp1
$ns attach-agent $UE2 $udp2
$ns attach-agent $base_station $null1
$ns attach-agent $base_station $null2
# Connect UDP traffic from UEs to the Base Station
$ns connect $udp1 $null1
$ns connect $udp2 $null2
# Set up Constant Bit Rate (CBR) traffic for UE1 and UE2 to send data to Base Station
set cbr1 [new Application/Traffic/CBR]
$cbr1 set packetSize_ 512
$cbr1 set interval_ 0.1
$cbr1 attach-agent $udp1
set cbr2 [new Application/Traffic/CBR]
$cbr2 set packetSize_ 512
$cbr2 set interval_ 0.1
$cbr2 attach-agent $udp2
# Schedule the traffic for both UEs
$ns at 1.0 “$cbr1 start”
$ns at 1.5 “$cbr2 start”
$ns at 4.0 “$cbr1 stop”
$ns at 4.5 “$cbr2 stop”
# Enable tracing to capture simulation events
set tracefile [open cellular_trace.tr w]
$ns trace-all $tracefile
# Define a finish procedure to stop the simulation
proc finish {} {
global ns tracefile
$ns flush-trace
close $tracefile
exit 0
}
# Run the simulation for 5 seconds
$ns at 6.0 “finish”
$ns run
Explanation:
- Wireless Nodes and Channels: In this instance, a wireless channel is described to replicate cellular communication among UEs and a Base Station (BS). The nodes are set up to utilize 802.11 MAC and Omni antennas for communication.
- Base Station (BS): A fixed node performs as a base station to receive data from UEs.
- User Equipment (UE): Two mobile nodes (UE1 and UE2) are signify mobile devices that transmit data to the BS.
- Traffic: Constant Bit Rate (CBR) traffic is transmitted from both UEs to the BS using UDP agents.
- Cellular Mobility in NS2
In a real cellular network, mobile devices (UEs) are move across distinct areas, frequently activating handovers among distinct base stations. We can be replicated mobility by setting up movement models for the UEs in NS2.
Example: Adding Mobility to UEs in Cellular Network
# Set initial positions for the UEs and simulate mobility
$UE1 setdest 200.0 200.0 10.0 ;# UE1 moves to (200, 200) at 10 m/s
$UE2 setdest 250.0 250.0 5.0 ;# UE2 moves to (250, 250) at 5 m/s
This instance replicates UE mobility in which both UEs move towards new positions with distinct speeds in the course of the simulation.
- Advanced Cellular Network Simulations in NS2
4.1. Handover Simulation
We can be replicated handover in a multi-cellular environment by deploying numerous base stations and dynamically attaching UEs to distinct base stations according to their signal strength or location. It encompasses observing the distance or signal strength among the UE and BS, and activating a handover when the UE moves very far from its current BS.
Example:
# Create another base station (BS2)
set base_station2 [$ns node]
$base_station2 set X_ 300.0
$base_station2 set Y_ 300.0
$base_station2 set Z_ 0.0
# Implement logic to handover UE1 to base_station2 when it moves closer to it
$ns at 3.0 “$ns connect $udp1 $null2” ;# Handover UE1 from base_station1 to base_station2
4.2. Adding Core Network Elements
Even though NS2 doesn’t have a direct model for Evolved Packet Core (EPC) elements (like the Serving Gateway (SGW) or Packet Gateway (PGW)), we can replicate the behaviour of these components by making wired backbones, which signify the core network. Traffic from UEs can be routed via these wired networks that replicating the role of the EPC.
# Simulate a wired core network
set core_network_node [$ns node]
$ns duplex-link $base_station $core_network_node 100Mb 10ms DropTail
$ns duplex-link $core_network_node $base_station2 100Mb 10ms DropTail
- Analysing Cellular Network Performance Metrics
After running the simulation, the trace file made by NS2 will include all events, like packet transmission, reception, and drops. We can examine performance parameters such as throughput, packet delivery ratio (PDR), and handover latency by parsing the trace file.
Example: Parsing the Trace File for Throughput
We can utilize AWK or Python scripts to process the trace file and compute throughput or other performance parameters:
# AWK script to count the number of packets received by the base station
awk ‘{ if ($1 == “r” && $4 == “AGT” && $7 == “udp”) count++; } END { print “Packets received: “, count; }’ cellular_trace.tr
- Visualization with NAM
To envision the cellular network and monitor the packet flow among UEs and the base station, we can utilize NAM (Network Animator):
# Enable NAM trace file for visualization
set namfile [open cellular_simulation.nam w]
$ns namtrace-all $namfile
# Launch NAM after the simulation ends
proc finish {} {
global ns namfile
$ns flush-trace
close $namfile
exec nam cellular_simulation.nam &
exit 0
}
After running the simulation, we can open the NAM file to envision the network topology and packet flow.
- Simulating Cellular Network Projects with NS3
For more exact cellular network simulations, containing 4G/LTE and 5G networks, it is suggested to use NS3 that has built-in support for LTE via the LENA module. NS3 offers realistic models for:
- eNodeB (LTE Base Station).
- UE (User Equipment).
- Evolved Packet Core (EPC) with PGW and SGW elements.
- Handover management, QoS, and advanced aspects such as MIMO.
Here, we indicated the procedure that contains basic to advanced cellular network simulations to replicate and analyse the Cellular network projects within NS2 tool. Should it be wanted, we are equipped to deliver deeper informations and relevant details on this projects.
