# Realistic Simulation for Body Area and Body-To-Body Networks
## 3 Proposed Simulator
### Deterministic (Bio-Mechanical) Radio Link and Mobility Modeling
#### 3.2.2 Intra-BAN and Inter-BAN Channel Models
Further, a selected link (_i.e., \"ear-belt\"_) is shown to be coherent with the semi-deterministic approach presented in Section 3.1. However, Table 7 shows the most interesting link types, where the deterministic approach is far more realistic than the IEEE 802.15.6 proposed channels [73]. It is important to note that the E-CM3-B model provides higher and more accurate time variations, which are due to two main reasons. First, time-varying mobility traces with accurate distances have enabled more accurate path loss results in comparison with static CM3-B, as can be seen in Figure 12. Second, \"LOS/NLOS\" link types are identified, and specific path loss modifications in the enhanced models are as follows:  
* If the link type is LOS, then we use Equations (8) and (9) only with the dynamic distances to compute the path loss. * Else, if the link type is NLOS, then we use Equations (8) and (9) with the dynamic distances to compute the path loss. Further, an additional NLOS factor is used as an add-on to the model. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Path Loss Model (Parameters)** & **Values at 900 MHz** & **Values at 2.45 GHz** \\ \hline \(P_{0}\), dB & 0.6512 & 0.0026 \\ m, dB/cm & 48.7212 & 46.0931 \\ \(P_{1}\), dB & 1.1519\({}^{-6}\) & 7.4683\({}^{-8}\) \\ \(\varphi_{p}\), dB & 3.2 & 3.6 \\ \hline \hline \end{tabular}
\end{table} 
Table 6: Channel model for the narrow band (_i.e.,_ CM3-B). Figure 11: Comparison of static and time-varying distances under different scenarios over time. (**a**) Time varying distances between the right knee and left knee; (**b**) Time varying distances between the right ankle and left ankle; (**c**) Time varying distances between the head and right ankle. As an example, on average, 13% extra of the factor (which was determined experimentally in [74]) should be added in the case of NLOS links. This factor has been added in every NLOS link in the enhanced models. Table 7 shows three different links (_i.e._, \"right knee-left knee\", \"right ankle-left ankle\" and \"right toe-left toe\"), which contains both space (_i.e._, distance) and time variations (_i.e._, mobility). Statistical results, including mean, standard variation, as well as correlation coefficients, are presented for four channel models under two frequencies. It is quite obvious that the mean variations among the enhanced and standard channel models are very close, and in terms of standard deviations, there are slight differences. However, the major difference is in the time correlation. It can be observed that the enhanced models with dynamic distances keep track of certain patterns, which can be periodic, such as shown in Table 7 and in Figure 12. It is to be noted that the results are presented for the \"_jogging/running_\" scenarios shown in the latter part of Figure 11, as it provided higher mobility. Though for the \"_walking_\" scenario, the differences between the comparisons of the correlation coefficient are relatively less.