In comparison with the copper tag in air, both the presence of the body and usage of the e-textile conductor manifested themselves as higher antenna resistance
. This corresponds with the dissipation of energy in these materials.
By comparing these values with Tables 2-3, the remarks for the proportion of the effect of a substrate can be stated: the use of a substrate 1) decreases antenna resistance
significantly, which improves matching of these antennas required to use without matching components and 2) increases relatively capacitance of C/L-ratio, which is the reason to enable slightly wider bandwidth.
In particular, [V.sub.open] is the open circuit voltage occurring at the end of the antenna when no load is connected and [Z.sub.A] is the antenna impedance, where [X.sub.A] is the antenna reactance and [R.sub.A] is the antenna resistance
which is a combination of the radiation resistance, modelling the radiated power, in series with the loss resistance and modelling the conductive and dielectric losses.
Considering 75 [ohm] load resistance (only the antenna resistance
), this corresponds to around 750 mV.
The talk mode rotation angle is always positive, suggesting displacements towards the inductive Smith chart region when the user effects increase the antenna resistance