## 3 System-Level Configuration  
In this section, we present the setup adopted for the C-RAN system-level assessment, detailing the target scenarios that we will evaluate. In the C-RAN, the static clustering technique partitions the network into three adjacent TRP sets where each user is served by at least one TRP, while the others perform inter-user interference. For the C-RAN with a cluster size of 1, we have a traditional cellular system. For instance, with cluster size 3, the network is partitioned into three adjacent TRP sets where each user is served by three adjacent TRPs. The inter-user interference only comes from the other clusters. The  
Figure 5: Indoor factory scenario layout. considered scenarios are almost all based on modified 3 GPP environments as specified in the previous section: the smart city environment, which corresponds to a modified urban micro outdoor/indoor environment; the stadium with pitch, which has no correspondence to any 3 GPP environment but corresponds to an open-air gathering environment; and the indoor factory, which is based on the reference scenario of 3 GPP, with the same name for an indoor factory environment area (see Figures 3-5). In our study, the operating frequency varied depending on the scenario. The bandwidth was also variable depending on the 5G NR numerology chosen for the scenario. The bandwidth was \(B\) = 50 MHz for numerology 0 and \(B\) = 0.4 GHz for numerology 3. In all scenarios, the IoT devices or terminals were uniformly placed within a minimum distance of 1 m around their respective BSs and RIS panels. The red dots on the previous figures illustrating the scenarios represent the IoT devices or users. The IoT devices or users are randomly and uniformly placed in each scenario at a given distance and angle from the BSs or from the associated RIS panel. There is a probability of having LOS and NLOS links depending on the distance \(d\). In the case of the NLOS links, there is fading due to multipaths following a Rayleigh distribution with shadowing, according to a lognormal distribution. All parameters and equations can be found in [15]. For each scenario, the probability of LOS (\(P_{LOS}\)) can be calculated as follows:  
_Smart City Scenario_  
\[\left\{ \begin{array}{l}P_{LOS}=1,d<18\\ P_{LOS}=(18/d+\exp(-d/36)\times(1-18/d)),d>18\end{array} \right. \tag{1}\]  
_Stadium w/Pitch Scenario_  
\[\left\{ \begin{array}{l}k_{sub}=44.8\times((h_{BS}-h_{UT})/(22.5-h_{UT})),h_ {BS}=25\\ P_{LOS}=\exp(-(d/k_{sub}))\end{array} \right. \tag{2}\]  
_Indoor Factory Scenario_  
\[\left\{ \begin{array}{l}k_{sub}=2.2,h_{BS}=2\\ k_{sub}=2.2\times((h_{BS}-h_{UT})/(6-h_{UT})),h_{BS}=8\\ P_{LOS}=\exp(-(d/k_{sub}))\end{array} \right. \tag{3}\]  
where \(h_{BS}\) and \(h_{UT}\) are the BS and terminal antenna heights. In all scenarios, we first evaluate the case where only BSs are active, i.e., RIS are not active. In this case, the coverage area of the BSs must include almost the whole scenario area. Large blue circles are illustrating this situation for every scenario. For the smart city scenario, one IoT device can be connected to each corresponding RIS panel at height of 10 m, with a total of 20 RISs and 4 BSs deployed. There are five RISs inside each BS coverage area, as represented in Figure 3. For the stadium with pitch scenario, up to three users can also be connected to each corresponding RIS panel at a height of 10 m, with a total of 22 RISs and 4 BSs deployed. There are an average of 5.5 RISs inside each BS coverage area, as represented in Figure 4. For the indoor factory scenario, one user can be connected to each corresponding RIS panel at a height of 2 or 8 m, with a total of 16 RISs and 2 BSs deployed. There are eight RISs inside each BS coverage area, as represented in Figure 5.  
The total power transmitted by each BS or IoT device depends on the scenario and the frequency carrier. At 100 GHz, the power was set to 30 mW (14.8 dBm) for the indoor factory, whereas 3.16 W (35 dBm) or 250 mW (24 dBm) were transmitted from each BS at 28 GHz, in the case of the stadium.