Table 3.

List of Greek Symbols and Corresponding Definitions.

Symbol	Definition
$(\alpha ,\beta )$	Constants corresponding to the capacitor and diode turn-on voltage at EH circuit
$\chi$	Mean corresponding to the confidence interval formula
$\delta$	Time splitting factor corresponding to TP
$\overline{ϵ}$	Threshold limit corresponding to Algorithm 1
$\sqrt{\eta }$	Reflection efficiency coefficient of the PR device
$\gamma$	Z-value corresponding to the confidence interval formula
$\kappa$	Parameter to compute the intermediary fraction during the Dinkelbach process
$\mathbf{\Lambda }$	Vector corresponding to the Lagrange dual variables: $({\lambda }_1,{\lambda }_2,{\lambda }_3)$
$\nu$	The number of observations corresponding to the confidence interval formula
${\omega }_E$	Weighing coefficient corresponding to the harvested energy
${\omega }_P$	Weighing coefficient corresponding to the transmit power
${\omega }_R$	Weighing coefficient corresponding to the data throughput
$\rho$	Power splitting ratio
$\sigma$	Standard deviation
${\sigma }_{n_{u_a}^2}$	Noise variance corresponding to $n_{u_a}$
${\sigma }_{n_{u_{ID}}^2}$	Noise variance corresponding to $n_{u_{ID}}$
${\sigma }_{n_P^2}$	Noise variance corresponding to $n_P$
${\sigma }_{n_R^2}$	Noise variance corresponding to $n_R$
${\sigma }_{n_1^2}$	Parameter to refer to ${\sigma }_{n_P^2}$ or ${\sigma }_{n_R^2}$ according to the chosen scheme
$\tau$	Time-switching ratio
$\Theta$	Metric to represent $\tau$ or $\rho$ interchangeably
${{\rm Y}}_{1,D}^{\mathrm{PS}}$	SNR obtained at the end-user with PS scheme via direct link
${{\rm Y}}_{1,D}^{\mathrm{TS}}$	SNR obtained at the end-user with TS scheme via direct link
${{\rm Y}}_{1,P}$	SNR estimated at the PR via first hop indirect link
${{\rm Y}}_{1,R}$	SNR estimated at the AR via first hop indirect link
${{\rm Y}}_1$	Parameter to refer to ${{\rm Y}}_{1,P}$ or ${{\rm Y}}_{1,R}$ according to the chosen scheme
${{\rm Y}}_{2,P}^{\mathrm{PS}}$	SNR obtained at the end-user with PS scheme via second hop PR device link
${{\rm Y}}_{2,P}^{\mathrm{TS}}$	SNR obtained at the end-user with TS scheme via second hop PR device link
${{\rm Y}}_{2,R}^{\mathrm{PS}}$	SNR obtained at the end-user with PS scheme via second hop AR device link
${{\rm Y}}_{2,R}^{\mathrm{TS}}$	SNR obtained at the end-user with TS scheme via second hop AR device link
${{\rm Y}}_2^{\mathrm{PS}}$	Parameter to refer to ${{\rm Y}}_{2,P}^{\mathrm{PS}}$ or ${{\rm Y}}_{2,R}^{\mathrm{PS}}$ according to the chosen scheme
${{\rm Y}}_2^{\mathrm{TS}}$	Parameter to refer to ${{\rm Y}}_{2,P}^{\mathrm{TS}}$ or ${{\rm Y}}_{2,R}^{\mathrm{TS}}$ according to the chosen scheme
$\varsigma$	Minimum demanded data throughput
$\xi$	Minimum demanded harvested energy
$\Xi$	Metric combining reflection/amplification coefficients of PR/AR, respectively