## 6 Simulations Results and Discussions
### Critical Discussion  
In this manuscript, we proposed a novel clustering and routing protocol for UAV-based data collection from SNs. Our approach addresses cluster overlapping and utilizes UAVs as CHs for efficient data packet collection. We introduced a unique mobile CH technique for energy-efficient cluster formation without a setup phase. Our routing protocol extends to the MAC layer to enhance network reliability. We developed an innovative data flow model that prioritizes reliability and reduces the SN's energy consumption. Additionally, our protocol incorporates WuRs to reduce SN energy consumption during communication. The proposed protocol exhibits outstanding performance in several key aspects. Results from Sections 6.1 and 6.2 reveal a substantial increase in SNs' life span, with the proposed protocol extending their survival by 12.55, 12.13, 9.55, 6, 8.92, and 4.72 times compared to LEACH, LEACH-C, SEP, TEEN, IEE-LEACH, and EEECA-THWSN, respectively. Additionally, employing the EEUCH protocol allows SNs to maintain their energy up to 1080 rounds, significantly outperforming other protocols where SNs perish as early as round 86, 89, 113, 180, 121, and 229. Moreover, the EEUCH protocol excels in packet collection, gathering 11.74, 7.78, 9.05, 11.22, 5.10, and 5.06 times more packets compared to LEACH, LEACH-C, SEP, TEEN, IEE-LEACH, and EEECA-THWSN, respectively. The protocol also demonstrates improved network stability and extended lifetime, as evidenced by the evaluation in Table 3. Furthermore, the EEUCH protocol achieves better average throughput, transmitting 11.74, 7.78, 9.05, 11.22, 5.11, and 5.06 times more bits per round compared to LEACH, LEACH-C, SEP, TEEN, IEE-LEACH, and EEECA-THWSN, respectively. Control overhead is a significant performance metric that measures the additional signaling and communication overhead associated with various operations in a protocol. This includes tasks such as cluster formation, CH selection, and coordination between CHs and member SNs. Control overhead encompasses the exchange of control messages such as cluster setup messages, join requests, CH advertisements, and cluster synchronization messages. Our proposed EEUCH protocol introduces certain elements that contribute to this metric. These include WuC reception, joining request transmission, TDMA frame reception and recognition of dedicated slots, and AcK reception for transmitted data. To quantify the control overhead generated by EEUCH, we consider sizes of 4000, 88, 32, 160, and 160 bits for data, AcK, WuC, join request, and TDMA slots allocation frame, respectively. The data size is taken from our benchmark routing protocols, as indicated in Table 2. The sizes of WuC and ACK are obtained from [31]. The sizes of joining request and TDMA slots allocation frames are assumed to be the same as those of request to send (RTS) and clear to send (CTS) frames in the IEEE 802.11 standard [40]. The assumption is made on the basis that the information carried by these frames are identical. This includes details such as the source and destination addresses, duration of the intended transmission, and a sequence number. The control overhead can be expressed as follows:  
\[\textit{Control Overhead}=\frac{\textit{Total size of the control packets}}{\textit{Total size of the data packets}}\times 100, \tag{12}\]  
where _total size of the control packets_ refers to the cumulative size of all control packets transmitted in the network per round, and the _total size of the data packets_ refers to the size of all data packets transmitted, per round. The total control overhead generated by the proposed EEUCH protocol is 11% in a single UAV round. This calculation takes into account that each SN transmits only one data packet in a single round. The information coverage ratio is another significant metric that evaluates the effectiveness of SNs deployment in covering the monitored area within a WSN. It assesses the extent to which the deployed SNs capture and monitor the target FoI.