Thanks James, I have repeated the measurements a couple of times with different motes (at least three motes) in an open space wide parking lot empty of cars, and in a football field as well.
The antenna of my sensors is PCB and as you mentioned, just a tiny shift increases or reduces the transmission range. Even for the worst case (the lowest range), the transmission range of power level 3 (and higher levels) is still much higher than that of level 1 and 2. The idea is to show higher power levels generate more strong noise and wider range of interference. Cheers, Abbas > Hi Abbas, > > Have you tried repeating your experiment in different environments, e.g. > outdoors? Transmission ranges in the real world are unpredictable because > they are affected by a great many factors, including the layout of > buildings and surfaces around you, which can have unpredictable effects. > The big jump is probably a random effect of signal bouncing, refractions, > fading etc when you had the motes in a particular place. > > I have also found that the orientation of the antenna has a big effect > with motes, especially the on-board kind which is embedded into the pcb - > just a tiny shift can significantly improve or reduce transmission. > > So I would repeat it in multiple different locations and orientations and > take an average. I would expect that to show more consistency. > > Also have you double checked the power levels against the cc2420 > datasheet. > > Good luck > > James > > ________________________________ > From: arghav...@cs.otago.ac.nz<mailto:arghav...@cs.otago.ac.nz> > Sent: �03/�05/�2017 21:44 > To: > tinyos-help@millennium.berkeley.edu<mailto:tinyos-help@millennium.berkeley.edu> > Subject: [Tinyos-help] Transmission Range > > Hello everybody, > > I measured the transmission range of CC2420 radio chip for a couple of > power levels. I have got these measurements: > > power level 1 ----> 120 cm > power level 2 -----> 150 cm > power level 3 -----> 3550 cm > power level 4 -----> 4050 cm > power level 5 -----> 4450 cm > power level 6 -----> 5020 cm > > Does anyone know what is the reason for such a big jump in the > transmission range of power level 2 to power level 3. Notice that there is > no a big difference between the output power of level 2 and 3. I think is > it around -30 dBm for level 2 and -25dBm for level 3. > > *** I defined the transmission range as the maximum distance between > transmitter and receiver so that at least 90% of the packets are > delivered. *** > > All the best, > Abbas > > _______________________________________________ > Tinyos-help mailing list > Tinyos-help@millennium.berkeley.edu > https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help > _______________________________________________ > Tinyos-help mailing list > Tinyos-help@millennium.berkeley.edu > https://www.millennium.berkeley.edu/cgi-bin/mailman/listi _______________________________________________ Tinyos-help mailing list Tinyos-help@millennium.berkeley.edu https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
