Table 1 Simulation parameters

Reference distance: R_min

30 m

Variance of log-normal shadowing fading: \(\sigma _{k}^{2}\)

8 dB

Transmission bandwidth: B

20 MHz

PA efficiency at the relay: η_r

0.39

Channel coherence bandwidth: B_c

180 kHz

PA efficiency at UEs: η_u

0.3

Channel coherence time: T_c

10 ms

Circuit power consumption at the relay: P_cR

1 W

Fixed power consumption: P_f

20 W

Circuit power consumption at UEs: P_cU

0.1 W

Power efficiency of float-point operation: \(\frac {R_{\text {flops}}}{\eta _{\mathrm C}}\)

1800

baseband processing power consumption at the relay: P_RR

29.6 W