LTE SimServer
The purpose of this tutorial is to show you how to do throughput test with LTE SimServer. LTE SimServer is a built in utiliy that comes with LTE callbox that generate UDP packets for throughput test. In this tutorial, I will demonstrate not only the basic operations of LTESimServer but also throughuts for various different bandwidth.
If you are using iperf, there are cases where it is very hard to get very high throughput mainly because it is difficult to find exact options to flood enough amount of packets from iperf to radio protocol stack. Even if you managed to figure out those options with one setup(e.g, for one PC) and it may not work with another setup and you need to figure it out again for the changed setup. With LteSimServer, you can easily reach near max throughput as long as PHY throughput support (
It is assumed that you are familiar with the basic operations of the callbox and I would not explain about the very basic operations of callbox. If you are not familiar with the basic operation of the callbox, refer to other tutorials like LTE Attach, SA setup, NSA setup etc.
NOTE : In some test, you will see the throughput does not reach the ideal throughput. It is because the test is done with commercial mobile phone which does not expose RF port to perform the test in conductive way.
Test Procedure Summary
This test applies to any of enb, mme, ims configuration as long as those configurations are valid and does not cause any error during the execution.
Step 1 : Run lte service (i.e, run 'service lte restart')
Step 2 : Run linux screen (i.e, run 'screen -r')
Step 3 : Power on UE and wait until the connection is established
Step 4 : Ensure that UE has been assigned with at least one IP (you can check this with 'ue' command in (mme) screen on callbox)
Step 5 : Open up another terminal window and go to the directory /root/mme
Step 6 : Run SimServer (i.e, run './ltesim_server')
Step 7 : Send some data to UE from SimServer(e.g, run 'cbr_send 192.168.3.2 100M 600')
Table of Contents
- LTE SimServer
Test Setup
Test setup for this tutorial is as shown below.
- Since this test is for Out of the box testing, I used the default configuration(cfg) file without changing anything in it
- SIM Card used in this tutorial is the one delivered with the system as it is.
- If you want to change the configuration, The tutorial Configuration Guide would help
Test 1 : LTE FDD b7 BW 5 Mhz 2x2 MIMO
In this test, I used default LTE configuration as shown below.
Following is the configuration in enb.default.cfg
Check cell configuration and confirm that they (frequency, band, bandwidth, mimo etc) are configured as you intented
Power on UE and Get UE attached to the cell and check the IP assigned to UE
Go to the directory /root/mme and run ./ltesim_server
Generate IP throughput
Verify the throughput with 't' command and tweak radio link condition to achieve the throughput as much as possible.
Test 2 : LTE FDD b7 BW 20 Mhz 2x2 MIMO
In this test, I used a configuration file that are modified from enb-b7-20Mhz-2x2.cfg which was copied from gnb-sa.cfg as shown below.
Following is the configuration in enb-b7-20Mhz-2x2.cfg
Check cell configuration and confirm that they (frequency, band, bandwidth, mimo etc) are configured as you intented
Power on UE and Get UE attached to the cell and check the IP assigned to UE
Go to the directory /root/mme and run ./ltesim_server
Generate IP throughput
Verify the throughput with 't' command and tweak radio link condition to achieve the throughput as much as possible.
Test 3 : NR SA TDD n78 BW20 Mhz 2x2 MIMO
In this test, I used default NR SA configuration (gnb-sa.cfg) as shown below.
Following is the configuration in gnb-sa.cfg
Check cell configuration and confirm that they (frequency, band, bandwidth, mimo etc) are configured as you intented
Power on UE and Get UE attached to the cell and check the IP assigned to UE
Go to the directory /root/mme and run ./ltesim_server
Generate IP throughput
Verify the throughput with 't' command and tweak radio link condition to achieve the throughput as much as possible.
Test 4 : NR SA TDD n78 BW50 Mhz 2x2 MIMO
In this test, I used gnb-sa-50Mhz.cfg which is copied and modified from gnb-sa.cfg as shown below.
Following is the configuration in gnb-sa-50Mhz.cfg
Check cell configuration and confirm that they (frequency, band, bandwidth, mimo etc) are configured as you intented
Power on UE and Get UE attached to the cell and check the IP assigned to UE
Go to the directory /root/mme and run ./ltesim_server
Generate IP throughput
Verify the throughput with 't' command and tweak radio link condition to achieve the throughput as much as possible.
Test 5 : NR SA TDD n78 BW100 Mhz 2x2 MIMO, 2 x sdr50
In this test, I used the configuration gnb-sa-2sdr-0-1.cfg which was copied and modified from gnb-sa.cfg as shown below.
Following is the configuration in gnb-sa-2sdr-0-1.cfg
Check cell configuration and confirm that they (frequency, band, bandwidth, mimo etc) are configured as you intented
Power on UE and Get UE attached to the cell and check the IP assigned to UE
Go to the directory /root/mme and run ./ltesim_server
Generate IP throughput
Verify the throughput with 't' command and tweak radio link condition to achieve the throughput as much as possible.