NetSim Long Term Evolution (LTE) Networks library includes LTE/LTE-A networks, LTE Femto Cell, LTE D2D and LTE VANET. The LTE libraray allows you to connect, if required, with Internetwork devices such as Routers, Switches etc running Ethernet, Wireless LAN, IP Routing, TCP / UDP.

1. Ver 11.1 1
LTE and LTE-Adv
Contents
1 Introduction..........................................................................................................................2
2 Simulation GUI......................................................................................................................2
2.1 Create Scenario..........................................................................................................................2
2.2 Set Node, Link and Application Properties................................................................................3
2.3 Enable Packet Trace, Event Trace & Plots (Optional)................................................................5
2.4 Run Simulation...........................................................................................................................5
3 Model Features.....................................................................................................................6
3.1 Physical speed of the LTE Air Interface......................................................................................6
3.2 for PHY rate calculation.............................................................................................................7
3.3 Carrier Aggregation ...................................................................................................................8
3.3.1 LTE Operating Bands:................................................................................................8
3.3.2 LTE Transmission modes ..........................................................................................9
3.3.3 LTE PHY layer parameters: .....................................................................................10
3.3.4 CA Configurations:..................................................................................................10
3.3.5 CA Bandwidth Classes:............................................................................................11
3.3.6 CA Configuration naming conventions:..................................................................11
3.3.7 CA Configuration in NetSim:...................................................................................12
4 Featured Examples..............................................................................................................12
4.1 LTE MIMO ................................................................................................................................12
4.2 LTE VANET Handover...............................................................................................................14
5 Reference Documents .........................................................................................................18
6 Latest FAQs.........................................................................................................................19

2. Ver 11.1 2
1 Introduction
NetSim Long Term Evolution (LTE) Networks library includes LTE/LTE-A networks, LTE
Femto Cell, LTE D2D and LTE VANET. The LTE libraray allows you to connect, if required,
with Internetwork devices such as Routers, Switches etc running Ethernet, Wireless LAN, IP
Routing, TCP / UDP.
2 Simulation GUI
In the Main menu select New Simulation Long-Term Evolution Networks (LTE/LTE-A,
Femto cell, D2D, LTE VANET)
2.1 Create Scenario
Adding MME- Click on the Router icon in the tool bar, click and drop the MME (Mobility
Management Entity) onto the environment. MME can be connected to an eNB or to a Router.
Adding ENB - Click on the Evolved node B (ENB) icon in the toolbar and click it onto the
environment. Each eNB should atleast be connected to one UE.

3. Ver 11.1 3
Adding Relay - Click on the Relay icon from the ENB icon in the toolbar and click it onto the
environment. . Relay can be connected to an eNB or to a UE. Each eNB should atleast be
connected to one UE.
Adding UE – Click on the UE (User Equipment) icon in the toolbar, click and drop UE onto
the environment.
Connect the devices - Select the Wired/Wireless links icon in the toolbar and connect the
devices by clicking on the device 1 and device 2.
2.2 Set Node, Link and Application Properties
Right click on the appropriate node or link and select Properties. Then modify the parameters
according to the requirements. Routing Protocol in Application Layer of router, MME and all
user editable properties in DataLink Layer and Physical Layer of Access Point and Wireless
Node are Global i.e. changing properties in one node will automatically reflect in the others in
that network. Transmission Mode Index of ENB, Relay and UE are also global properties. The
following are the main properties of LTE ENB

4. Ver 11.1 4
The following are the main properties of LTE UE
Click on the Application icon present on the ribbon and set properties.Multiple applications can
be generated by using add button in Application properties.

5. Ver 11.1 5
Set the values according to requirement and click OK.
Detailed information on Application properties is available in section 5 of NetSim User
Manual.
2.3 Enable Packet Trace, Event Trace & Plots (Optional)
Click Packet Trace / Event Trace icon in the tool bar and check Enable Packet Trace / Event
Trace check box and click OK. To get detailed help, please refer sections 7.5 and 7.6 in User
Manual. Select Plots icon for enabling Plots and click OK.
2.4 Run Simulation
Click on Run Simulation icon on the top toolbar.

6. Ver 11.1 6
Set the Simulation Time and click on OK.
3 Model Features
3.1 Physical speed of the LTE Air Interface
The theoretical calculation for the LTE Air Interface is as follows:
One Resource block can have 12 subcarriers (each carrier is 15 kHz) in frequency domain
and 0.5ms (7 symbols) in time domain.
Thus, total number of symbols per resource block = 12 * 7 = 84
Each symbol can accommodate certain number of bits based on the modulation scheme as
per the table below
Modulation
scheme
Bits per
symbol
QPSK 2
16-QAM 4
64-QAM 6

7. Ver 11.1 7
The table below shows the number of resource blocks available for different LTE channel
bandwidths.
Channel
Bandwidth (MHz)
5 10 15 20
Resource Blocks
(RB)
25 50 75 100
No. of subcarriers
(RB*12)
300 600 900 1200
Occupied bandwidth
(MHz)
4.5 9 13.5 18
Note: In LTE 10% of total bandwidth is used for guard band. For example if the channel bandwidth is 20MHz,
then 2MHz is used for guard band. Thus, if 180 kHz has 1 RB, 18 MHz will have 100 RBs
3.2 for PHY rate calculation
In LTE for 20MHz, there are 100 Resource blocks and each Resource block has 12*7 = 84
symbols
Example: PHY rate calculation for 20MHz band, using 64-QAM and 4*4 Tx Rx antennae
 For 20 MHz there are 100 Resource blocks
 Each resource block has 12*7 = 84 symbols
 100 resource blocks have 8400 symbols
 1 sub frame = 1 ms = 2 time slots
 16800 symbols per subframe (or per ms)
 64-QAM can transmit 6 bits per symbol
 1 subframe using 64-QAM modulation can transmit 100800 bits/ms
 100.8*10^6 bits per second or 100.6 Mbps
 This is for a 1*1 Tx Rx antenna and for 4*4 Tx Rx antennae 100.8*4 = 403.2 Mbps
The above note explains the theoretical method of calculating the LTE PHY Data rate, where
there are no channel (propagation) losses.
However in the real world there is signal attenuation due to propagation losses. Thus the
calculation for PHY Data rate in NetSim is based on the Transport Block Size which is specified
in the standard. This calculation is as follows
Any signal received at the receiver has a SNR (signal to noise ratio).
Based on the SNR a CQI value is calculated.
The SNR - CQI Table is available in LTE.h in NetSim and is per the LTE standard
Based on the SNR and the CQI an MCS value is calculated

8. Ver 11.1 8
The SNR CQI MCS table is available in LTE.h in NetSim and is per the LTE standard
Based on the MCS the TBS Index is calculated, again from a table available in LTE.h
which is per the LTE Standard
Based on the TBS Index the TBS Table is looked up and the transport block size is
retrieved.
Approximately 25% of overhead is used for controlling and signalling. And hence effective
PHY data rate is 300 Mbps.
3.3 Carrier Aggregation
Carrier aggregation is used in LTE-Advanced in order to increase the bandwidth, and thereby
increase the bitrate. Each aggregated carrier is referred to as a component carrier, CC. The
component carrier can have a bandwidth of 1.4, 3, 5, 10, 15 or 20 MHz and a maximum of five
component carriers can be aggregated, hence the maximum aggregated bandwidth is 100
MHz.
In FDD the number of aggregated carriers can be different in DL and UL as shown in the figure
above. However, the number of UL component carriers is always equal to or lower than the
number of DL component carriers. The individual component carriers can also be of different
bandwidths. For TDD the number of CCs as well as the bandwidths of each CC will normally
be the same for DL and UL.
3.3.1 LTE Operating Bands:
The table below describes the LTE frequency bands defined in 3GPP that was referred for our
implementation.

9. Ver 11.1 9
Fdd Lte Bands & Frequencies
Lte Band
Number
Uplink
(Mhz)
Downlink
(Mhz)
Width Of
Band
(Mhz)
Duplex
Spacing
(Mhz)
Band Gap
(Mhz)
1 1920 – 1980 2110 - 2170 60 190 130
2 1850 – 1910 1930 - 1990 60 80 20
3 1710 – 1785 1805 -1880 75 95 20
4 1710 – 1755 2110 - 2155 45 400 355
5 824 – 849 869 - 894 25 45 20
6 830 – 840 875 - 885 10 35 25
7 2500 – 2570 2620 - 2690 70 120 50
8 880 – 915 925 - 960 35 45 10
9 1749.9 - 1784.9 1844.9 - 1879.9 35 95 60
10 1710 – 1770 2110 - 2170 60 400 340
11 1427.9 - 1452.9 1475.9 - 1500.9 20 48 28
12 698 – 716 728 - 746 18 30 12
13 777 – 787 746 - 756 10 -31 41
14 788 – 798 758 - 768 10 -30 40
15 1900 – 1920 2600 - 2620 20 700 680
16 2010 – 2025 2585 - 2600 15 575 560
17 704 – 716 734 - 746 12 30 18
18 815 – 830 860 - 875 15 45 30
19 830 – 845 875 - 890 15 45 30
20 832 – 862 791 - 821 30 -41 71
21 1447.9 - 1462.9 1495.5 - 1510.9 15 48 33
22 3410 – 3500 3510 - 3600 90 100 10
23 2000 – 2020 2180 - 2200 20 180 160
24 1625.5 - 1660.5 1525 - 1559 34 -101.5 135.5
25 1850 – 1915 1930 - 1995 65 80 15
26 814 – 849 859 - 894 30 / 40 10
27 807 – 824 852 - 869 17 45 28
28 703 – 748 758 - 803 45 55 10
29 n/a 717 - 728 11
30 2305 – 2315 2350 - 2360 10 45 35
31 452.5 - 457.5 462.5 - 467.5 5 10 5
Note: NetSim supports FDD currently. Also Downlink only configurations (bands 29 and 32) are not
supported.
3.3.2 LTE Transmission modes
NetSim supports the following LTE Transmission modes:

10. Ver 11.1 10
 Transmission Mode 1- Using of a single antenna at eNodeB
 Transmission Mode 2- Transmit Diversity (TxD)
 Transmission Mode 3- SU-MIMO Spatial Multiplexing: Open-Loop
 Transmission Mode 4- SU-MIMO Spatial Multiplexing: Closed-Loop
 Transmission Mode 5- MU-MIMO Spatial Multiplexing: Per the LTE standard.
Transmission mode 5 uses MU MIMO where the number of receive antenna is fixed at 2.
3.3.3 LTE PHY layer parameters:
Channel Bandwidth(MHz) 1.4 3 5 10 15 20
No. of Resource Block(NRB) 6 15 25 50 75 100
No. of occupied subcarriers 73 181 301 601 901 1201
IFFT(Tx) /FFT size(Rx) 128 256 512 1024 1536 2048
No. of sampling frequency
(sampling rate)
1.92 3.84 7.68 15.36 23.04 30.72
samples per slot 960 1920 3840 7680 11520 15360
3.3.4 CA Configurations:
CA combinations are divided into intra-band (contiguous and non-contiguous) and inter-band
non-contiguous. Intra-band contiguous and inter-band combinations, aggregating two
Component Carriers (CCs) in downlink, are specified from Release 10. The Intra-band
contiguous CA configuration refers to contiguous carriers aggregated in the same operating
band. The Intra-band non-contiguous CA configuration refers to non-contiguous carriers
aggregated in the same operating band. The Inter-band CA configuration refers to aggregation
of component carriers in different operating bands, where the carriers aggregated in each band
can be contiguous or non-contiguous.

11. Ver 11.1 11
3.3.5 CA Bandwidth Classes:
Following table shows Carrier Aggregation Bandwidth Class in terms of total number of RBs
used by aggregated carrier.For example, CA Bandwidth Class 'B' says N_RB,agg <= 100. It
means that total aggregated RB should be less than 100 and aggregated Tx Bandwidth for
Class A cannot be greater than 20MHz, limited to 1 component carrier(CC) in the band.
Class ATBC Maximum
number of
CC
NRB,agg MHz
A N <= 100 20 1
B 25 < N <= 100 20 2
C 100 < N <= 200 40 2
D 200 < N <= 300 60 3
E 300 < N <= 400 80 4
F 400 < N <= 500 100 5
I 700 < N <= 800 160 8
ATBC - Aggregated Transmission Bandwidth Configuration, CC - Component Carrier, RB -
Resource Block, NRB, agg - Number of the aggregated RBs within the fully allocated Aggregated
Channel bandwidth
Note: NetSim currently supports CA Bandwidth classes A, B and C.
3.3.6 CA Configuration naming conventions:
To understand the naming conventions of a CA configuration and the bandwidth combination
set usage, let us relate to CA_1C configuration. This CA configuration states that the UE can
operate on Band 1, with two continuous components carriers, with a maximum of 200 RBs.
The bandwidth combination set then states that the allocation of those 200 RBs can be either
75 RBs on both CCs or 100RBs on both CCs.

12. Ver 11.1 12
3.3.7 CA Configuration in NetSim:
Carrier Aggregation is supported in NetSim’s LTE devices such as ENB, HNB and Relay. In
the LTE_Interface of these devices i.e., in the interface connected to the UE’s CA can be
configured.Users can choose the carrier aggregation type.
Based on the selected carrier aggregation type, CA configurations available in the drop down
to choose from varies dynamically.
4 Featured Examples
Sample configuration files for all networks are available in Examples Menu in NetSim Home
Screen. These files provide examples on how NetSim can be used – the parameters that can
be changed and the typical effect it has on performance.
4.1 LTE MIMO
Open NetSim, Select Examples->LTE-and-LTE-A-> LTE-MIMO

13. Ver 11.1 13
Settings done in sample network:
1. Disable TCP in all devices in Transport Layer
2. Change all wired link speeds by 10 Gbps (10000Mbps)
3. Create 4 CBR applications from Wired Node to UEs with generation rate
300Mbps(Packet size=1460, IAT=37micro sec)
4. Set the channel bandwidth of carriers to 20MHz in CA1 and CA2 of Interface1_LTE
properties
5. Set Channel characteristics to Pathloss only, Pathloss model to LOG_DISTANCE and
Pathloss exponent to 2
6. Simulate for 10 seconds
Results:
Transmission mode index (Tx mode,
Tx. Antenna Count, Rx. Antenna Count)
Application_Throughput (Mbps)
0(1, 1, 1) 36.61, 36.61, 36.64, 36.53
1(2, 2, 2) 36.61, 36.61, 36.64, 36.53
2(3, 2, 2) 72.58, 72.70, 72.69, 72.59
3(3, 4, 2) 72.58, 72.70, 72.69, 72.59
4(5, 4, 2) 145.26, 145.47, 145.42, 145.09
4(5, 8, 2) 145.26, 145.47, 145.42, 145.09

14. Ver 11.1 14
4(5, 16, 2) 145.20, 145.47, 145.60, 145.17
Results may vary based on Node positions
Transmission mode 1: SISO  uses only 1 Transmit antenna. Since Round Robin
scheduling is running all applications see equal throughput.
Transmission mode 2: MIMO Tx. Diversity  Sends copies of same information via multiple
antennae. This will lead to higher reliability but the throughput will remain the same.
Transmission mode 3: MIMO Spatial Multiplexity Open Loop  used to achive high data
rates. Here the data is divided and sent via various antennae. You can see an increase in
throughput.
Transmission mode 4: MU-MIMO  In multi user the data is sent and received through
multiple antennae. You can see a further increase in throughput.
4.2 LTE VANET Handover
Open NetSim, Select Examples->LTE-and-LTE-A-> LTE-VANET-Handover
Settings done for this sample experiment:
 Set Application BSM (Basic_Safety_Message) from Vehicle_1 to Vehicle_2
 Set Packet Size as 1460 bytes and Inter Arrival Time as 1 Sec (1000000microsec)

15. Ver 11.1 15
 Open UE/Vehicle General Properties and select the Configuration.sumo.cfg file from
the Docs folder of NetSim Install Directory < C:Program FilesNetSim
StandardDocsSample_ConfigurationLTELTE_VANET_Handover> as shown
below:
 Enable Packet trace option
 Run simulation for 400(by default)
Inference:
Check packet animation window you are likely to see the Vehicle_1 and 2 undergoing hand
over between the two ENB’s (Base Station’s)

16. Ver 11.1 16
As in the simulation results window, In LTE Metrics window users can find the information
about Handover count.

17. Ver 11.1 17
Open Packet trace option from results window and filter CONTROL_PACKET_TYPE/
APP_NAME column to LTE_Handover_Request and LTE_Handover_Request_Ack users can
see that handover packet transmitting between two ENB’s through MME.
Note: In LTE it is based on SNR (soft hand over)
Currently users can configure two Component Carriers (CCs) using NetSim’s GUI. However
users can go up to 5 carriers for experimentation using NetSim’s CLI mode by editing the
Configuration.netsim/Configuration.xml file.

18. Ver 11.1 18
Further the bandwidth for each CC can be chosen from the list of allowed bandwidths, based
on which the PHY layer parameters as shown in a table in section 3.3.5
5 Reference Documents
Based on 3GPP 36 series specifications for Long Term Evolution Networks

19. Ver 11.1 19
6 Latest FAQs
Up to date FAQs on NetSim’s LTE library is available at
https://tetcos.freshdesk.com/support/solutions/folders/14000107855