Impact of UE movement on Throughput

Open NetSim, Select Examples ->5G NR -> UE Movement vs Throughput then click on the tile in the middle panel to load the example as shown in below Figure 4‑66.

Graphical user interface, application Description automatically generated

Figure 4‑66: List of scenarios for the example of UE Movement vs Throughput

NetSim UI displays the configuration file corresponding to this experiment as shown below in Figure 4‑67.

Chart Description automatically generated

Figure 4‑67: Network set up for studying Throughput vs. UE Movement

The following set of procedures were done to generate this sample:

Step 1: A network scenario is designed in NetSim GUI comprising of 1 gNB, 5G-Core, and 1 UE and 1 Wired Node in the “5G NR” Network Library.

Step 2: Grid Length was set to 5100 m x 5100 m.

Step 3: The device positions are set as per the table given below Table 4‑71.

Device UE_8 gNB_7 Wired_Node_10
x- axis 500 500 3500
y- axis 1 0 1020

Table 4‑71: Device general properties

Step 4: The following properties were set in Interface (5G_RAN) of gNB

Parameter Value
Tx_Power 40
gNB Height 10m
CA Type Single Band
CA Configuration n78
DL-UL Ratio 4:1
Numerology 0
Channel Bandwidth 10 MHz
MCS Table QAM64LOWSE
CQI Table TABLE3
Propagation Model Urban Macro
Pathloss Model 3GPPTR38.901-7.4.1
LOS_NLOS_Selection User Defined
LOS Probability 0
Shadow Fading Model None
Fading and Beamforming NO_FADING_MIMO_UNIT_GAIN
O2I Building Penetration Model Low Loss Model

Table 4‑72: gNB >Interface (5G_RAN) >Physical layer properties

Step 5: Set Tx_Antenna_Count and Rx_Antenna_Count as 2 and 1 in gNB properties > Interface(5G_RAN) > Physical Layer.

Step 6: Set Tx_Antenna_Count and Rx_Antenna_Count as 1 and 2 in UE properties > Interface(5G_RAN) > Physical Layer.

Step 7: In the General Properties of UE 8, set Mobility Model as File Based Mobility

Step 8: A CBR Application was generated from Wired Node 10 i.e. Source to UE 8 i.e. Destination with Packet Size remaining 1460Bytes and Inter Arrival Time remaining 1168µs.

Step 9: The Transport Protocol was set to UDP.

Step 10: Additionally, the “Start Time(s)” parameter is set to 1s, while configuring the application.

File Based Mobility: In File Based Mobility, users can write their own custom mobility models and define the movement of the mobile users. Create a mobility.txt file for UE’s involved in mobility with each step equal to 4 sec with distance 100 m.

The NetSim Mobility File (mobility.txt) format is as follows:

$time 0.0 "$node_(7) 500.0 1.0 0.0"

$time 4.0 "$node_(7) 500.0 101.0 0.0"

$time 8.0 "$node_(7) 500.0 201.0 0.0"

$time 12.0 "$node_(7) 500.0 301.0 0.0"

$time 16.0 "$node_(7) 500.0 401.0 0.0"

$time 20.0 "$node_(7) 500.0 501.0 0.0"

$time 24.0 "$node_(7) 500.0 601.0 0.0"

$time 28.0 "$node_(7) 500.0 701.0 0.0"

$time 32.0 "$node_(7) 500.0 801.0 0.0"

$time 36.0 "$node_(7) 500.0 901.0 0.0"

$time 40.0 "$node_(7) 500.0 1001.0 0.0"

$time 44.0 "$node_(7) 500.0 1101.0 0.0"

$time 48.0 "$node_(7) 500.0 1201.0 0.0"

$time 52.0 "$node_(7) 500.0 1301.0 0.0"

$time 56.0 "$node_(7) 500.0 1401.0 0.0"

$time 60.0 "$node_(7) 500.0 1501.0 0.0"

$time 64.0 "$node_(7) 500.0 1601.0 0.0"

$time 68.0 "$node_(7) 500.0 1701.0 0.0"

$time 72.0 "$node_(7) 500.0 1801.0 0.0"

$time 76.0 "$node_(7) 500.0 1901.0 0.0"

$time 80.0 "$node_(7) 500.0 2001.0 0.0"

$time 84.0 "$node_(7) 500.0 2101.0 0.0"

$time 88.0 "$node_(7) 500.0 2201.0 0.0"

$time 92.0 "$node_(7) 500.0 2301.0 0.0"

$time 96.0 "$node_(7) 500.0 2401.0 0.0"

$time 100.0 "$node_(7) 500.0 2501.0 0.0"

Step 11: Plots is enabled in NetSim GUI.

Step 12: Run simulation for 100s.

Results:

Graphical user interface, chart Description automatically generated

Figure 4‑68: Plot of Throughput (Mbps) vs Time (sec)

Discussion

As the UE moves away from the gNB, the Application throughput starts reducing. The maximum throughput of 10 Mbps is obtained until 40 sec. At 40s the UE is 1000m away from the gNB. Then the throughput drops to 9.3 Mbps at 40 sec and at time 48 sec (when UE is 1200m away from gNB), the throughput drops to 6 Mbps and at time 52 sec (when UE is 1300m away from gNB), the throughput drops to 3.26 Mbps and subsequently keeps dropping as till the end of the simulation as the UE continues to move further away from the gNB.