Table 2 Symbols and descriptions.

From: Spectral efficiency enhancement in multiuser NOMA over Nakagami-m fading channels through power allocation and pairing strategies under hardware and SIC imperfections

Symbols

Description

m

Nakagami-m shape parameter

M

Number of users

\(h_{s-j}\)

Channel coefficients between gNB and \(\text {UD}_j\)

\(g_{s-j}\)

Instantaneous channel po gain between gNB and \(\text {UD}_j\)

\(\delta _{s-j}\)

Distance between gNB and \(\text {UD}_j\)

\(\eta\)

Path loss parameter

\(\alpha _j\)

PA factor for \(\text {UD}_j\)

\(P_{t}\)

Power budget

\(y_{s-j}\), \(y_{s}\)

Received signals for DL and UL

\(\sigma _n^2\)

Noise variance

\(R_{UD_j}^{DL/UL}\)

SE for \(\text {UD}_j\) in DL/UL

\(S^{DL/UL}_{NOMA}\)

SSE in DL/UL

\(\tilde{\beta }_j\)

Minimum required SE for \(\text {UD}_j\)

\(\Theta _{UE_j}^{DL/UL}\)

Channel gain range causing outage for \(\text {UD}_j\) in DL/UL

\(PO^{DL/UL}_{\text {UD}_j}\)

Probability of outage for \(\text {UD}_j\) in DL/UL

\(\lambda ^2\)

Distortion power due to HI

\(\lambda\)

Standard deviation of HI

\(\varepsilon\)

iSIC distortion parameter

\(\Gamma (\cdot )\)

Gamma function

\(f_X(x)\)

PDF

\(F_X(x)\)

CDF

E(.)

Expectation operator

Var(.)

Variance operator