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5G communication environments are expected to be used alone in a few actual cases. Instead, typically, they are expected to be added to existing communication environments with LTE, Wi-Fi, etc. In these environments, the spurious emissions generated in the devices can result in communication interference.

Spurious emissions are defined as excess signals other than the communication signals themselves, and they include communication signals from other communication and high-order harmonics.

Note: The settings may vary for different releases of NetSim. Please follow the steps mentioned under the appropriate release. The following article contains steps to be followed for NetSim v13.1, v13.2 and v13.3

The sample configuration file and experiment file are attached below for reference. Please download and extract the file based on the version of NetSim you are using.

Scenario:

Network Settings:

1. Configure the properties as shown in the table below:

2. Set Uplink speed and Downlink speed as 10000 Mbps.

3. Set the Tx Antenna Count as 4 and Rx Antenna Count as 8 in UE properties.

4. Configure a Downlink applications with source node as 10 destination node as 8. Set the Transport Protocol to UDP in both the applications along with other settings given in the table below:

5. SNR can be seen in LTENR_Radio_Measurement Log file. It can be enabled by following the steps mentioned in section 3.20 in 5G Technology library manual. 

5. Run simulation for 1.1 sec. After the simulation completes note down the throughput from the application metrics table which is part of the results dashboard.

Result:

Upon analyzing the impact of spurious noise on the Throughput and SNR, 

We can see that as spurious noise increases throughput and SNR drops accordingly.

Code Modification: 

The source code of the LTENR_PHY.c file which is part of the LTE_NR source code project is modified as shown below (changes highlighted in red):

static double LTENR_PHY_calculateThermalNoise(double bandwidth)

{

       double noise = BOLTZMANN * TEMPERATURE * bandwidth * 1000000; //in W

       double spurious_noise = 1;// 1dB to 20dB

       noise *= 1000; // in mW

       double noise_dbm = MW_TO_DBM(noise);

       noise_dbm += spurious_noise;

       return noise_dbm;

}

Scenario:

Network Settings:

1. Configure the properties as shown in the table below:

2. Set Uplink speed and Downlink speed as 10000 Mbps.

3. Set the Tx Antenna Count as 4 and Rx Antenna Count as 8 in UE properties.

4. Configure a Downlink applications with source node as 10 destination node as 8. Set the Transport Protocol to UDP in both the applications along with other settings given in the table below:

5. SNR can be seen in LTENR_Radio_Measurement Log file. It can be enabled by following the steps mentioned in section 3.20 in 5G Technology library manual. 

5. Run simulation for 1.1 sec. After the simulation completes note down the throughput from the application metrics table which is part of the results dashboard.

Result:

Upon analyzing the impact of spurious noise on the Throughput and SNR, 

We can see that as spurious noise increases throughput and SNR drops accordingly.

Code Modification: 

The source code of the LTENR_PHY.c file which is part of the LTE_NR source code project is modified as shown below (changes highlighted in red):

static double LTENR_PHY_calculateThermalNoise(double bandwidth)

{

       double noise = BOLTZMANN * TEMPERATURE * bandwidth * 1000000; //in W

       double spurious_noise = 1;// 1dB to 20dB

       noise *= 1000; // in mW

       double noise_dbm = MW_TO_DBM(noise);

       noise_dbm += spurious_noise;

       return noise_dbm;

}