Table 1 Simulation parameters

\(\sigma _{0,1}^{2} = E\left [ {{{\left | {{h_{0,1}}} \right |}^{2}}} \right ]\)

0.0625 for (d=2, r=4)

Channel gain from BS to U₁

\(\sigma _{0,2}^{2} = E\left [ {{{\left | {{h_{0,2}}} \right |}^{2}}} \right ]\)

0.0514 for (d=2.1, r=4)

Channel gain from BS to U₂

\(\sigma _{0,E}^{2} = E\left [ {{{\left | {{h_{0,E}}} \right |}^{2}}} \right ]\)

0.0514 for (d=2.1, r=4)

Channel gain from BS to E

\({\alpha _1} = {\sigma _{0,2}^{2}} \left / \delta \right.\)

0.4514 for \(\delta = {\sum \nolimits }_{i = 1}^{2} {\sigma _{0,i}^{2}} \)

Allocation power factor of U₁

\({\alpha _2} = {\sigma _{0,1}^{2}} \left / \delta \right.\)

0.5486 for \(\delta = {\sum \nolimits }_{i = 1}^{2} {\sigma _{0,i}^{2}} \)

Allocation power factor of U₂

\(R_{1}^{*}\)

0.1 BPCU

Bit rate threshold of U₁

\(R_{2}^{*}\)

0.1 BPCU

Bit rate threshold of U₂

ρ₀

Optional

SNRs at BS

S

Optional

The antennae at BS

U

Optional

The antennae U_i and E