Dear Wben Jab (If thats your name), Looking at your operating frequency your cross over distance is around 86m. Thus when you experiment communication above this distance, the TwoRay propagation takes place anything below though you are using TwoRay only FreeSpace takes into effect.
>From the both RxThreshold, you will reach 300m and 1000m transmit range respectively. Nothing would be wrong in the RF point of view unless you changed your transmission power or RXThreshold in between. I am not sure where you are reading to confirm your packet receive. This should be done at the physical layer. If you are reading from the MAC layer, if there is a mechanism to define a packet error rate this could be the reason the received packet is discarded due to the failed integrity test of the content of the received packet. Do check on this. Good Luck. Saravanan K On Wed, Mar 27, 2013 at 2:03 PM, <wben-...@labri.fr> wrote: > > Dear All, > > I want to ask about the receving RxThreshold. I compute it for two > distances, one with 300m and the other with 1000m, using TwoRayGround > propagation model. > I have for 300m , the following output: > distance = 300 > propagation model: TwoRayGround > > Selected parameters: > transmit power: 0.281838 > frequency: 9.14e+08 > transmit antenna gain: 1 > receive antenna gain: 1 > system loss: 1 > transmit antenna height: 1.5 > receive antenna height: 1.5 > > Receiving threshold RXThresh_ is: 1.76149e-10 > > > Then, I applied with the same parameters for distance 1000m, and I > have the following output. > distance = 1000 > propagation model: TwoRayGround > > Selected parameters: > transmit power: 0.281838 > frequency: 9.14e+08 > transmit antenna gain: 1 > receive antenna gain: 1 > system loss: 1 > transmit antenna height: 1.5 > receive antenna height: 1.5 > > Receiving threshold RXThresh_ is: 1.42681e-12 > > I used the first receiving threshold 1.76149e-10 with distance of 300m > of communication range. And I find that the communication is close to > 300m. > > However, when I increased the distance with 1000m of communication > range (RXThresh_ is: 1.42681e-12), then I found that the maximum > communication range between nodes is 550m. > It seems strange to me, that's why I want to ask, if I had to change > the initialization parameters (Frequency, Transmission Power,..), > because I didn't change them (I used them as their default parameters > in threshold.cc file). > > Could you please, give me a hand, and if I have to modify some other > parameters in WirelessPhy. > > Thank you, and > Best regards. > >
