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Simple Frequency Histograms of Alpha

Using Obtained Data to reach to a suitable alpha value:

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Filtering Landmarks

If we are not interested in useless using delay to distance mapping for the landmarks not possibly becoming a part of final few landmarkslandmarks too far away from the target to be usable in the geolocation algorithm, we can neglect very high large values of RTT landmarks (as high RTT is possibly because of longer physical distance of landmark from the target)between landmarks and targets. But sometimes it's possible that our target is lying in such a geographical location where there are no active landmark is present in its nearer locationsnearby. In such a case probably some far distantly located landmarks would be candidates for the final selection, so we can't make any prior estimate of RTT value the threshold maximum RTT beyond which we should neglect landmarks. Probably one better choice can be that we perform delay to distance mapping of a fixed number of landmarks for any target and leave any other landmarks (using Sorted RTTs).
The above method means that after identifying a tier1 landmark for any target, we should go delay to distance mapping only for the tier0 landmarks of that particular regiondo not use the landmarks measurement may depend on the landmark and target regions involved. If we want to avoid making such useless measurements then we need to identify the region of the target early on in the process.