Hi Miklos, Yes, I have done it and many other tests to discard other reasons. The conclusion is that in the same conditions the two measures give different values in dBm. In this case, which measure do you thing should we trust? Do you agree that the ED measure should be equal or lower than the RSSI measure since it only considers IEEE 802.15.4 power?
Thanks in advance, BR Marc El 05/10/2011, a las 12:03, Miklos Maroti escribió: > Hi Marc, > > 10 dBm difference between two motes is completely normal. You should > reverse the roles of the two nodes and compare the result. > > Best, > Miklos > > 2011/10/5 Marc Barceló <[email protected]>: >> Hi Miklos, >> >> Thanks for the answer. I have not changed the RF230DriverLayerP file. In >> fact, I have used both measurements in two different motes but using exactly >> the same conditions. I think it is normal to have some dB between them, but >> I think the difference is too high. Any idea about the reason then? >> >> On the other hand, since the ED measure only measures the IEEE 802.15.4 >> packets power, should it not give always equal or less power than the RSSI >> measure, which takes into account every signal received in the measured >> region? >> >> Thanks in advance for the help, >> >> Marc >> >> >> El 05/10/2011, a las 10:03, Miklos Maroti escribió: >> >>> Hi Marc, >>> >>> Have you changed the RF230DriverLayerP file? I think the ED and RSSI >>> measurements are not performed at the same time. The ED is done >>> automatically by the hardware after the SYNC byte is received, while >>> the RSSI is done manually when the first interrupt is handled. This >>> could cause some difference. >>> >>> Best, >>> Miklos >>> >>> 2011/10/5 Marc Barceló <[email protected]>: >>>> Hello to everyone, >>>> >>>> I am a researcher working on WSN, using IRIS motes (which use RF230 Radio >>>> Hardware). I am measuring the received power from one mote to another. The >>>> RF230 datasheet says that two different measures can be used, Energie >>>> Detection (ED) or Received Signal Strength Indicator (RSSI). To convert >>>> the measured values to dBm, according to the datasheet, for the first case >>>> it is necessary to do: PRF = ED_VAL -91. For the second case the following >>>> has to be done PRF = RSSI_BASE_VAL + 3•(RSSI - 1). The problem is that >>>> these measures does not seem to be equivalent since using the ED measure I >>>> receive more power( a difference greater than 10 dB) in comparisson with >>>> the RSSI measure. I am using the Basic operating mode so, since what I >>>> know, both measures should be very similar. >>>> >>>> I would appreciate any help, >>>> >>>> Best Regards >>>> _______________________________________________ >>>> Tinyos-help mailing list >>>> [email protected] >>>> https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help >>>> >> >> _______________________________________________ Tinyos-help mailing list [email protected] https://www.millennium.berkeley.edu/cgi-bin/mailman/listinfo/tinyos-help
