## 5 Simulation Results
Particularly, we note that the BER of the case \(N=8\) is lower than that of the case \(N=1\). This is in contrast to the trend exhibited by the expectation of \(\text{SINR}_{e}\) in Figure 3. This is because when a MRC receiver is used at Eve, an  
Figure 4: The expectation of the power of the desired signal and AN received by Eve, with different numbers of receive antennas at Eve. Figure 3: The expectation of \(\text{SINR}_{b}\) and \(\text{SINR}_{e}\) with optimal beamforming in the function of the location of Eve \(\theta_{e}\). increase in the number of receive antennas reduces the fading of the equivalent channel. Therefore, even though the average SINR of the case \(N=8\) is smaller than that of the case \(N=1\), its BER is still better than that of the \(N=1\) case, due to the diversity gain of the receive antenna array. For comparison purposes, the expectation of \(\text{SINR}_{e}\) without using AN is simulated in the function of the location of [PERSON] \(\theta_{e}\), as shown in Figure 6. The shape of the beam can be observed for different \(M\) values. We note that as more antennas are used, the beam becomes narrower and the sidelobes become smaller. Figure 5: The simulated BERs of Eve in the function of the location of [PERSON] \(\theta_{e}\). Figure 3.0 The expectation of \(\text{SINR}_{e}\) without using AN in the function of the location of [PERSON] \(\theta_{e}\). The BER performance of [PERSON] without using AN is also simulated and the results are presented in Figure 3.1 It can be observed that when the number of antennas is relatively small, even if [PERSON] and [PERSON] are far apart, the BER of [PERSON] remains at a low level, especially when [PERSON] is on the peaks of the sidelobes. The results of this figure demonstrate the necessity of using AN to prevent eavesdropping. Moreover, the strategy for maximizing the ergodic secrecy rate [16] has also been simulated. The power allocation factors are optimized. The expectations of \(\mathrm{SINR}_{b}\) and \(\mathrm{SINR}_{e}\) are presented in Figure 8 and the BER results are shown in Figure 3.2 It can be observed that the difference in SINR between [PERSON] and [PERSON] has increased compared to Figure 3, but the BER of [PERSON] decreases as the location of [PERSON] becomes farther. This is because this strategy does not directly degrade the SINR of [PERSON]. Figure 3.3 The expectations of \(\mathrm{SINR}_{b}\) and \(\mathrm{SINR}_{e}\) when the ergodic secrecy rate is maximized in the function of the location of [PERSON] \(\theta_{e}\). Figure 3.4 The simulated BERs of [PERSON] without using AN in the function of the location of [PERSON] \(\theta_{e}\). To clarify the impact of the Rician parameter, the case where \(K_{b}=14.8\) dB is simulated to compare with the results of \(K_{b}=10\) dB. The expectations of \(\mathrm{SINR}_{b}\) and \(\mathrm{SINR}_{e}\) are presented in Figure 3.5 We note that a higher \(K_{b}\) value leads to a degradation in the performance of [PERSON]. However, the trend of the eavesdropper's SINR decreasing as the location moves away from the user remains unchanged. Hence, the proposed algorithm can be applied for LoS channels with different K-factors to degrade the SINR performance of an eavesdropper. An example of the K-factor for different scenarios can be found in ([46], Figure 3.65-6). Figure 3.7 The expectation of \(\mathrm{SINR}_{b}\) and \(\mathrm{SINR}_{e}\) for \(K_{b}=\{10,14.8\}\) dB in the function of the location of [PERSON] \(\theta_{e}\). Figure 3.8 The simulated BERs when the ergodic secrecy rate is maximized in the function of the location of [PERSON] \(\theta_{e}\). To illustrate the effectiveness of the proposed algorithm for minimizing the QoS of the eavesdropper, the BLER of [PERSON] and [PERSON] are simulated in Figure 11 using Polar code as the ECC. Polar code [32] is an emerging channel coding technique for 5\({}^{th}\) generation (5G) mobile communication systems [47]. Polar code has been adopted for enhanced mobile broadband (eMBB) control channels.