## 3 Results
### Results Obtained at 100 mW (20 dBm) Input Power to the ARCM
#### 3.2.1 The ARCM Parameters  
The proximity of the body to the ARCM may have a significant impact on its performance. In the APD scenarios, mismatches between the obtained resonant frequencies and the nominal operating frequency of 2.45 GHz were observed: lower values in the range from 35% (ARCM on the forearm) to 45% (ARCM on the chest) (Table 5). However, in the CWED scenarios, the resonant frequency mismatches were discovered in the range from 7.8% (ARCM on the arm) to 12% (ARCM on the head) only. In turn, the S11 parameter values at 2.45 GHz varied from \(-\)0.561 dB (ARCM on the chest) to \(-\)0.992 dB (ARCM on the forearm) and from \(-\)3.21 dB (ARCM on the chest) to \(-\)4.24 dB (ARCM on the arm) for the APD and CWED exposure scenarios, respectively. These levels of the S11 parameter value result in the antenna input power being (12-20)% and (52-62)% of the output power from the RCM, respectively. In addition, differences in antenna gain and associated eirp were observed. The antenna gain varied in range from \(-\)17.5 dB (ARCM on the head) to \(-\)9.44 dB (ARCM on \begin{table}
\begin{tabular}{c c c} \hline \multirow{2}{*}{**Exposure Scenario**} & \multicolumn{2}{c}{**Measurement (Simulation)**} \\ \cline{2-3}  & **Resonant Frequency [GHz]** & **[EMAIL_ADDRESS] GHz [dB]** \\ \hline Free space & 2.400 (2.432) & \(-\)6.01 (\(-\)5.85) \\ APD 1 on the arm & 1.545 (1.602) & \(-\)0.914 (\(-\)0.849) \\ APD 1 on the forearm & 1.595 (1.631) & \(-\)0.865 (\(-\)0.926) \\ CWED 2 on the chest & 2.210 (2.208) & \(-\)3.13 (\(-\)3.53) \\ \hline \end{tabular} \({}^{1}\)APD—an exposure scenario that may be considered as a model of a disposable, adhesive plaster with the RCM located directly on the body (0 mm distance between RCM and body), 2 CWED—an exposure scenario that may be considered as a model of a classic, reusable, wearable electronic device located in a plastic housing where the RCM is 2 mm away from the body surface.  
\end{table} 
Table 4: The ARCM emission parameters obtained from measurement and simulation. \begin{table}
\begin{tabular}{c c c c c c} \hline \multirow{2}{*}{**Scenario**} & \multicolumn{4}{c}{**Simplified [S] (Anatomical [A]) Model of User’s Body**} \\ \cline{2-6}  & **Resonant Frequency [GHz]** & **[EMAIL_ADDRESS] GHz [dB]** & **Gain [dB]** & **eirp 1 [dB]** & **10g-SAR [W/kg]** \\ \hline \multicolumn{6}{c}{APD exposure scenario (RCM located directly on the body: 0 mm distance between the RCM and the body)} \\ \hline Head & 1.537 (1.562) & \(-\)0.837 (\(-\)0.886) & \(\mathbf{-17.5}\) (\(-\)14.3) & 2.43 (5.66) & 4.73 (4.76) \\ Arm & 1.551 (1.602) & \(-\)0.847 (\(-\)0.849) & \(-\)11.0 (\(-\)10.7) & 9.02 (9.26) & 5.35 (6.05) \\ Forearm & 1.561 (**1.631**) & \(\mathbf{-0.992}\) (\(-\)0.926) & \(\mathbf{-9.44}\) (\(-\)10.7) & **10.6** (9.26) & **6.20** (5.81) \\ Chest & 1.365 (\(\underline{1.359}\)) & \(-\)0.640 (\(-\)0.561) & \(-\)17.1 (\(-\)16.2) & 2.89 (3.76) & 5.28 (5.58) \\ \hline \multicolumn{6}{c}{CWED exposure scenario (RCM located located 2 mm away from the body surface)} \\ \hline Head & 2.159 (2.155) & \(-\)3.25 (\(-\)3.95) & \(-\)12.1 (\(-\)8.96) & 7.87 (11.1) & 3.91 (3.98) \\ Arm & 2.223 (**2.260**) & \(-\)4.07 (\(\mathbf{-4.24}\)) & \(-\)8.56 (\(-\)7.80) & 11.4 (12.2) & 4.14 (4.73) \\ Forearm & 2.214 (2.243) & \(-\)3.66 (\(-\)3.82) & \(\mathbf{-5.83}\) (\(-\)6.59) & **14.2**(13.4) & **5.13** (4.91) \\ Chest & 2.208 (2.169) & \(-\)3.53 (\(-\)3.21) & \(\mathbf{-12.4}\) (\(-\)11.9) & 7.56 (8.14) & 3.63 (3.96) \\ \hline \end{tabular} \({}^{1}\) eirp—equivalent isotropically radiated power; bold values—the maximum value in the particular subset; underlined values—the minimum value in the particular subset.  
\end{table} 
Table 5: The ARCM parameters (resonant frequency, S11 parameter, gain, equivalent isotropically radiated power (eirp)) and associated 10g-SAR calculated in exposure scenarios with various models of body parts (at 100 mW (20 dBm) input power to antenna, 1.0 duty cycle and 2.45 GHz).