Hi, I've been playing with the TDMA model and wanted to gauge the results of moving nodes around in the demo. The demo is 10 nodes all originally at approximate 40 degrees latitude +/-and -74.5 degrees longitude +/- with altitude fixed at 3.00. I started out by moving just a single node, node 1, and fixed it at that location for the duration of the demo. I noted when the node might disconnect, if at all. Since this is a precomputed pathloss model with a specified value of 90 for all nodes, I expected the OLSRLINKVIEW to remain mutually connected through the duration, no matter the location of node 1. However, it looks as though node 1 loses connectivity to all other nodes when I move it at or beyond -79.4 degrees longitude. This, according to my calculations, looks to approximately correspond to the distance/time of flight for the specified slot duration of 1500 usec. -79.3 remains connected and -79.5 certainly disconnects. (I didn't change the values of latitude and longitude for remaining 9 nodes that were originally specified but they move only slightly from their original positions, still roughly approximating the 1500 usec distance with the 1500 usec slotduration.) I revised the slotduration to 1600 usec on a separate run and observed that the model completely reconnected. I suspect that if I moved node 1 longitudinally an additional amount to correspond to 1600 usec time of flight, it too would disconnect in a like manner and indeed that is the case.
Is there a particular reason that the model would lose connectivity when distances exceed the specified slotduration? Since the pathloss is fixed value, I was expecting to be able to extend well beyond that and still retain connectivity, although impractical in the real world, but trying to achieve a related objective. The TDMA model staggers the tx slots from 1 to 10 and they don't appear to present any collision opportunity. Have I overlooked something?
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