[ laa-wifi-simple ] Wi-Fi is not detecting correctly LTE interference.

[pedro maia]

Dear,

I've just download the latest ns-3-lbt-9529febb7ebc at https://www.nsnam.org/wiki/LAA-WiFi-Coexistence and I've made a two simple examples for testing Wi-Fi and LTE (duty cycled) coexistence:

./waf --run scratch/laa-wifi-simple --command="%s --cellConfigA=Lte --cellConfigB=Wifi --d2=10 --lteDutyCycle=1 --RngRun=2"

Output:

Running simulation for 1 sec of data transfer; 5 sec overall

Operator A: LTE; number of cells 1; number of UEs 1

Operator B: Wi-Fi; number of cells 1; number of UEs 1

LTE duty cycle: requested 1, actual 1, ABS pattern 0000000000000000000000000000000000000000

Total txop duration: 0 seconds.

Total phy arrivals duration: 0 seconds.

--------monitorA----------

Flow 1 (1.0.0.2:49153 -> 7.0.0.2:9) proto UDP

  Tx Packets: 9123

  Tx Bytes:   9378444

  TxOffered:  75.0276 Mbps

  Rx Bytes:   9003224

  Throughput: 73.7901 Mbps

  Mean delay:  3.5215 ms

  Mean jitter:  0.189606 ms

  Rx Packets: 8758

--------monitorB----------

Flow 1 (12.0.0.1:49153 -> 18.0.0.2:9) proto UDP

  Tx Packets: 2629

  Tx Bytes:   2702612

  TxOffered:  21.6209 Mbps

  Rx Bytes:   411200

  Throughput: 9.90649 Mbps

  Mean delay:  289.701 ms

  Mean jitter:  0.661388 ms

  Rx Packets: 400

And a second simulation, just increasing the distance d2 for verifying the scenario with no interference:

./waf --run scratch/laa-wifi-simple --command="%s --cellConfigA=Lte --cellConfigB=Wifi --d2=1000 --lteDutyCycle=1 --RngRun=2"

Output:

Running simulation for 1 sec of data transfer; 5 sec overall

Operator A: LTE; number of cells 1; number of UEs 1

Operator B: Wi-Fi; number of cells 1; number of UEs 1

LTE duty cycle: requested 1, actual 1, ABS pattern 0000000000000000000000000000000000000000

Total txop duration: 0 seconds.

Total phy arrivals duration: 0 seconds.

--------monitorA----------

Flow 1 (1.0.0.2:49153 -> 7.0.0.2:9) proto UDP

  Tx Packets: 9123

  Tx Bytes:   9378444

  TxOffered:  75.0276 Mbps

  Rx Bytes:   9003224

  Throughput: 73.7901 Mbps

  Mean delay:  3.5215 ms

  Mean jitter:  0.189606 ms

  Rx Packets: 8758

--------monitorB----------

Flow 1 (12.0.0.1:49153 -> 18.0.0.2:9) proto UDP

  Tx Packets: 2629

  Tx Bytes:   2702612

  TxOffered:  21.6209 Mbps

  Rx Bytes:   411200

  Throughput: 10.372 Mbps

  Mean delay:  280.1 ms

  Mean jitter:  0.5951 ms

  Rx Packets: 400

As you can see, Wi-Fi still had a very high packet loss although there was no LTE interference (d2=1000). 

All the parameters not established at the ./waf command line follow the default values (no changes at the the .cc file).

Thank you all in advance for any comment about that.

[Tom Henderson]

This is  due to the default ItuInh indoor loss model that is configured for that example, as of changeset ns-3-lbt-9529febb7ebc of that repository.

If you try different RngRun values, you will observe quite different throughput depending on whether the model picked a favorable LOS or unfavorable NLOS condition.

I realize that this can be unexpected behavior for the most simple example, which is why the most recent revision on this repository reverts the default propagation loss model to be LogDistance for this example program.

Or, on the older version of the simulator that you are using, you can run the program like this:

./waf --run laa-wifi-simple --command="%s --cellConfigA=Lte --cellConfigB=Wifi --d2=1000 --lteDutyCycle=1 --RngRun=2 --indoorLossModel=ns3::LogDistancePropagationLossModel"


- Tom

[Anshu Bhan]

Hello

Can u share the code with me sir?

Regards 

Anshu NS3