Thus, the packet transmission time is 32 × 8/256 = 1 s, which is equal to T. We use a path loss exponent of 1.5 corresponding to practical spreading, and absorption according to Thorp, sensor node's communication range is between 50509 and 50510 m.
The variance of fading coefficient between two terminal (i, j) is determined by using a path-loss model in the form of ( {sigma}_{;i;j}^2=kern0.72em {d}_{kern0.24em i;j}^{kern0.36em -upsilon } ), and the path loss coefficient is assigned as υ = 4 [12].
The deterministic fading model G n m = 1 0 - 4 d n m - 3 is used with a path loss exponent of ρ = 3, transmitter and receiver gains of 1 and a 1 m reference path loss ratio of K nm = 10-4.
The derivation was carried out using a generalized path loss model that accounts for both large and small- scale path loss.
It is also assumed that by using a suitable path loss model, the distance between the transmitter and receiver can be derived by measuring the received power for the given transmission power.
Using a classical path loss model in the tunnel, we have shown a good agreement between measurements and simulations at 5.8 GHz showing that the method can be used to predict radio wave propagation in straight and curved rectangular tunnels for metro applications.
Thus, using a simplified path loss model and denoting by P R thr the SU receiver sensitivity threshold, as determined by hardware specifications, the transmission range R T i m of node i over channel m can be estimated as: R T i m = d 0 a P ( i ) P i, m G t G r P R thr · c 0 4 π d 0 f m 2 1 η (1).
Finally, some concluding remarks are given in Section 5. Using RSS together with a path loss (PL) and shadow fading model, a distance estimate between the BS and the MS can be obtained.
Description of a path loss model used for coverage planning of different radio propagation environments has been presented in Section 3. Section 4 explains the structure of the UMTS network instances used for simulating the proposed resource management approach.
If use replace L relay j in Equation 4 with L ̄ relay j, and use an average path loss calculated during a previous round as α because we can not get an accurate value, then we use the modified equation to determine the energy consumed by node n i j in layer j during the current round.
