Bug 2450 – LogDistancePropagationLossModel is not continuous

Bug 2450 - LogDistancePropagationLossModel is not continuous


Summary:	LogDistancePropagationLossModel is not continuous

Status:	RESOLVED FIXED

Product:	ns-3
Classification:	Unclassified
Component:	propagation
Version:	ns-3-dev
Hardware:	All All

Importance:	P5 minor
Assigned To:	Nicola Baldo

URL:
Keywords:

Depends on:
Blocks:
	Show dependency tree / graph

Reported:	2016-07-12 19:30 UTC by Tommaso Pecorella
Modified:	2016-10-12 15:28 UTC (History)
CC List:	1 user (show)

See Also:

Attachments
model behavior before patch (11.02 KB, application/pdf) 2016-10-12 15:19 UTC, Nicola Baldo	Details
model behavior after patch (11.02 KB, application/pdf) 2016-10-12 15:20 UTC, Nicola Baldo	Details
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Description Tommaso Pecorella 2016-07-12 19:30:55 UTC

The reference discussion is here:
https://groups.google.com/forum/#!topic/ns-3-users/bBEUYHwvZwU

Summarizing, LogDistancePropagationLossModel::DoCalcRxPower is not continuous when one reaches the minimum distance (minor nuisance, but still a nuisance).

Moreover, Krishna (the poster) also suggests to clarify if the units are in dBm or dB.

Comment 1 Nicola Baldo 2016-10-12 15:19:45 UTC

Created attachment 2611 [details]
model behavior before patch

Comment 2 Nicola Baldo 2016-10-12 15:20:28 UTC

Created attachment 2612 [details]
model behavior after patch

Comment 3 Nicola Baldo 2016-10-12 15:28:37 UTC

I've just fixed the discontinuity issue in changeset 4da9433a490d following Krishna's proposal, which I think made perfectly sense. See the attached figures for the change in model behavior. 

As for dBm vs dB: TX power is in dBm and gain values are in dB, and that's the way it should be. I think that the comments in the code and the doxygen documentation are already clear on this matter.