How to Implement Network 3D Beam Alignment in NS2
To implement the Network 3D Beam Alignment in ns2 which is a challenging task because ns2 mainly deals with packet-level network simulation and lacks the inherent support for physical-layer beamforming or 3D beam alignment. Though, you can extend the ns2 and replicating beam alignment at a high level, you can model the influence of beam alignment on packet transmission, delay or signal strength.
This alignment usually means to set up the antenna arrays of a transmitter and receiver to concentrate signal power in a certain direction, both in azimuth (horizontal) and elevation (vertical) angles. Beamforming and beam alignment are important elements of modern wireless communication systems, certainly in millimeter-wave (mmWave) and 5G networks. Be in touch with us to get best implementation results in Network 3D Beam Alignment in ns2 tool.
In this set up, we discussed about implementation of 3D Beam Alignment in ns2:
Steps to Implement Network 3D Beam Alignment in NS2
- Model 3D Beam Alignment in NS2: We have to simulate the impacts of beam alignment by altering parameters like signal strength, transmission power and delay depends on the beam alignment success or failure because ns2 lacks the support for physical antenna models.
- Extend NS2 with a Custom Model:
- Launch 3D beam alignment logic that modifies the transmission power or packet loss in terms of how well the beams amongst the transmitter and receiver are aligned.
- Replicate beam alignment success or failure by using the node locations and antenna orientation.
Example: Simulating the Impact of Beam Alignment in NS2
Measure the basic beam alignment according to the node location and antenna orientations to replicate 3D beam alignment. This score defines either the communication amongst two nodes is successful or not.
Step 1: Model Node Orientation and Beam Alignment
Compute the beam alignment score in terms of 3D position and orientation of the nodes by defining a procedure in the TCL script.
# Procedure to simulate 3D beam alignment
proc beam_alignment_score {tx_node rx_node} {
# Get the 3D positions of the transmitter and receiver nodes
set tx_x [$tx_node set X_]
set tx_y [$tx_node set Y_]
set tx_z [$tx_node set Z_]
set rx_x [$rx_node set X_]
set rx_y [$rx_node set Y_]
set rx_z [$rx_node set Z_]
# Calculate the difference in positions (distance vector)
set dx [expr $rx_x – $tx_x]
set dy [expr $rx_y – $tx_y]
set dz [expr $rx_z – $tx_z]
# Example: Calculate beam alignment score based on distance vector
# In a real scenario, you would use angle calculations (e.g., azimuth/elevation angles)
set alignment_score [expr abs($dx) + abs($dy) + abs($dz)]
# If alignment_score is below a threshold, consider the beams aligned
if { $alignment_score < 100 } {
return 1 ;# Aligned
} else {
return 0 ;# Misaligned
}
}
Step 2: Adjust Transmission Power Based on Beam Alignment
You can alter the transmission power or packet delivery success depends on whether the beam is aligned or not.
# Procedure to simulate packet transmission with 3D beam alignment
proc send_packet_with_beam_alignment {tx_node rx_node} {
global ns
# Check beam alignment between transmitter and receiver
set alignment [beam_alignment_score $tx_node $rx_node]
if { $alignment == 1 } {
puts “Beam aligned. Transmitting packet successfully.”
# Normal transmission (no modification)
} else {
puts “Beam misaligned. Reducing transmission power or dropping packet.”
# Adjust transmission parameters (e.g., reduce power or drop the packet)
set tx_power [expr 0.1] ;# Reduce transmission power due to misalignment
}
}
Step 3: Integrate Beam Alignment into the Simulation
You can incorporate the send_packet_with_beam_alignment approach into a wireless communication simulation, altering the packet transmission activities based on beam alignment.
# Define a simulator object
set ns [new Simulator]
# Define trace and nam files for output
set tracefile [open out.tr w]
set namfile [open out.nam w]
$ns trace-all $tracefile
$ns namtrace-all $namfile
# Define a ‘finish’ procedure to end the simulation and visualize in NAM
proc finish {} {
global ns tracefile namfile
$ns flush-trace
close $tracefile
close $namfile
exec nam out.nam &
exit 0
}
# Set up the topography for the simulation area
set topo [new Topography]
$topo load_flatgrid 1000 1000
# Define the wireless channel
set chan [new Channel/WirelessChannel]
# Configure wireless nodes with the IEEE 802.11 MAC protocol
$ns node-config -adhocRouting DSDV \
-llType LL \
-macType Mac/802_11 \
-ifqType Queue/DropTail/PriQueue \
-ifqLen 50 \
-antType Antenna/OmniAntenna \
-propType Propagation/TwoRayGround \
-phyType Phy/WirelessPhy \
-channel $chan
# Create transmitter and receiver nodes
set tx_node [$ns node]
set rx_node [$ns node]
# Set 3D positions for the nodes
$tx_node set X_ 100; $tx_node set Y_ 100; $tx_node set Z_ 10
$rx_node set X_ 800; $rx_node set Y_ 800; $rx_node set Z_ 15
# Simulate packet transmission with beam alignment
$ns at 1.0 “send_packet_with_beam_alignment $tx_node $rx_node”
# Schedule simulation end
$ns at 5.0 “finish”
# Run the simulation
$ns run
- Explanation of the Simulation
- Beam Alignment Calculation: The beam_alignment_score procedure estimates the alignment amidst the transmitter and receiver based on their 3D positions.
- Packet Transmission Based on Alignment: If the beams are aligned, normal packet transmission happens. If not, the transmission power is decreased, replicating the effect of misalignment.
- Adjusting Transmission Power: In the case of misalignment, the transmission power can be decreased, or packet loss can be presented to recreate beam misalignment.
- Advanced Implementation
For a more real-time simulation, you would:
- Calculate the actual beamforming angles (azimuth and elevation) amongst the nodes and use those angles to state if the beams are aligned.
- Simulate beam alignment over time, where nodes try to fine-tune their beams based on feedback from the receiver.
- Introduce beamforming gain: Maximize signal strength when the beams are aligned, or reduce it when they are askew.
- Simulating Dynamic Beam Alignment
You can also replicate a dynamic beam alignment process where the transmitter and receiver try to alter their beams over time to enhance alignment.
# Procedure to adjust the beam alignment dynamically over time
proc dynamic_beam_alignment {tx_node rx_node} {
global ns
# Adjust the position of the transmitter node slightly (simulate beam adjustment)
set current_x [$tx_node set X_]
set new_x [expr $current_x + 10]
$tx_node set X_ $new_x
# Check the beam alignment score again after adjustment
set alignment [beam_alignment_score $tx_node $rx_node]
if { $alignment == 1 } {
puts “Beams aligned after adjustment. Transmission successful.”
} else {
puts “Beams still misaligned after adjustment.”
}
# Schedule the next adjustment in 1 second
$ns at [expr [$ns now] + 1] “dynamic_beam_alignment $tx_node $rx_node”
}
# Schedule dynamic beam alignment adjustments
$ns at 2.0 “dynamic_beam_alignment $tx_node $rx_node”
The above manual have aggregated the valuable information including snippet codes about how to simulate the characteristics of the Network 3D (three dimensional) beam alignment to establish it in the ns2 environment simply by modifying the transmission power