Viktor, You should look up some resources on free space loss/propagation models. They will give you a starting place on modeling "gain" or in reality, attenuation as a result of distance.
The basic calculations will be something like this: Gain(dB) = TX Antenna/Power Gain(dB) + DistanceLoss(in dB, should be negative) +RX Antenna Gain(dB). In an ideal world, antennas are isotropic(perfect omnidirectional antennas), so they would contribute negligible to the calculation.(note: ideal_world != world_we_live_in). Therefore TX Antenna/Power Gain will only be determined by what transmission power level you select, and RX Antenna Gain would be be 0 dB. Then DistanceLoss is the only real unknown and you can use the formulas found for a Free Space Loss Propagation model. The TOSSIM gain is simply TX Power(which is selected by you) + DistanceLoss. Hope this helps, -Paul Viktor Zsoldos wrote: > Hi, > > http://docs.tinyos.net/index.php/TOSSIM#Configuring_a_Network says > *|add(src, dest, gain)|*: Add a link from /src/ to /dest/ with /gain/. > When /src/ transmits, /dest/ will receive a packet attenuated by the > /gain/ value. > > How can I decide/calculate the "normal", "common" gain values? For > example for micaz datasheet says the TX power is -24dB - 0dB, the > receive power is -94dB. Let's say the distance between 2 nodes is 20 > meters, no obstacles, or heavy noises. What is the method? > > Thanks! > > Viktor > > _______________________________________________ > 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/listinfo/tinyos-help
