stimation error models. The maximum power PB is set to 2 Watts. For comparison, we also include the case of OMA, since it represents the traditional access tech- nology. Observe that in order to reduce the inter-user interference, each OMA user relies exclusively on a single time slot. Thus, a total of K time slots are required instead of a sin- gle one in our scheme. To make a fair comparison, each SU's achievable data rate should be averaged over all K time slots, which becomes ROMA = log2(1 + SINROMA). Reduced Table 5.1 Simulation parameters. Parameters Values Number of SUs and PUs K =3,N=2 Noise powers 02 = 0.1, 02 = 0.01 Minimum required EH power Pks=0.01 Watt Maximum tolerable interference of PUs Pn.p = -18 dBm Estimated channel gains hk~CN(0,0.8)g-CN(0,0.1) Outage probability threshold Ek Ek.s En.p 0.05 Non-linear EH model Mk = 24 mW, ak = = 0.014 [24] 5.5 Numerical Results Perfect CSI NOMA bounded CSI error model OMA bounded CSI error model Minimum transmit power of the CBS(W) Figure 5.2 The empirical CDF of the minimum transmit power of the CBS under different channel conditions. CBS antenna number M = 10, PB = 2 Watts, Rmin = 1 bit/s/Hz. interference is achieved at the cost of a lower spectral and energy efficiency. We also observe that under both channel error models, the performance of NOMA is better than that of OMA. This is because for OMA, the lower spectral efficiency makes the SU data rate require- ment harder to be satisfied. Hence the CBS has to apply a higher transmission power to compensate for that, which leads to a much higher energy consumption. Figure 5.2 is gen- erated from 1,000 independent realizations of different channel conditions. As expected, the performance under perfect CSI is the best, since no additional power is used to compensate for the channel uncertainties. Figure 5.3 shows the minimum transmit power of the CBS as a function of the minimum required SNR of SUs, Yk,min As the SNR increases, the power increases under all CSI cases. Also, perfect CSI requires the least power,