## 3 Research Methodology  
The objective of this study is to evaluate the performance of four routing protocols (AODV, DSR, GRP, and OLSR) as well as enhance the performance of the OLSR protocol by tuning parameters for UANET. The MANET routing protocol is applied to UANET, although UANET is different from MANET. Developing a new protocol requires extensive research and practical experiments. This study's aim is to enhance the performance of the existing OLSR protocol for UANET. Standard OLSR architecture ignores wireless link quality, and route selection is dependent on the hop count measure, which ignores link quality and traffic load throughout the forward path.  
By reducing hop count, the distance traveled by each hop is increased, which reduces signal strength and increases the packet loss ratio. Although the optimum route is one with the fewest hops, there may be several routes with the same minimum length but vastly different quality in a network. Most minimal hop-count measures make arbitrary decisions that are unlikely to choose the optimum path. However, as illustrated in [39], reducing the hop count will not always result in increased throughput flow. Furthermore, because the shortest path is commonly selected as the routing path in shortest path routing, nodes on the shortest path will be overloaded more than others. The resources of a node, including  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Parameter** & **Standard Value** & **Range** \\ \hline Willingness & WILL\_DEFAULT(3) & \(\mathcal{R}\in\) [0, 7] \\ HELLO\_INTERVAL & 2 s & \(\mathcal{R}\in\) [1.0, 30.0] \\ TC\_INTERVAL & 5 s & \(\mathcal{R}\in\) [1.0, 30.0] \\ NEIGHB\_HOLD\_TIME & \(3\times\) REFRESH\_INTERVAL & \(\mathcal{R}\in\) [3.0, 100.0] \\ TOP\_HOLD\_TIME & \(3\times\) TC\_INTERVAL & \(\mathcal{R}\in\) [3.0, 100.0] \\ DUP\_HOLD\_TIME & 30 s & \(\mathcal{R}\in\) [3.0, 100.0] \\ \hline \hline \end{tabular}
\end{table}
Table 1: OLSR parameters and RFC 3626 [37] specified values.  
\begin{table}
\begin{tabular}{c c c c c c} \hline \hline
**Parameters** & **DSR** & **AODV** & **GRP** & **OLSR** & **E-OLSR** \\ \hline Protocol type & On-demand & On-demand & Proactive & Proactive & Proactive \\ \hline Multiple route & Yes & No & Yes & No & No \\ \hline Routing overhead & Low & High & Medium & Medium & Medium \\ \hline Route maintains & Route cache & Route table & Route table & Route table & Route table \\ \hline Route structure & Flat structure & Flat structure & Flat structure & Flat structure & Flat structure \\ \hline Route metric & Shortest path & Shortest path & Shortest path & Shortest distance & Shortest distance \\ \hline Congestion & Low & Medium & Medium & Medium & Medium \\ \hline Hop counts & Very high & Normal & High & Less & Less then OLSR \\ \hline \hline \end{tabular}
\end{table}
Table 2: Comparative analysis between routing protocols along with proposed E-OLSR.  
Figure 1: E-OLSR parameters used in UANET system.  
bandwidth, computing power, battery life, and memory storage, can be depleted by high demand. Eventually, packet loss and buffer overflow can arise if one of the overloaded nodes becomes congested, resulting in increased delay, lower throughput, and transport connection failure.  
Given these considerations, this paper proposes an enhancement of OLSR by optimizing parameters that can impact the link-quality and traffic-load awareness in the routing protocol. E-OLSR is the term given to the upgraded OLSR, which has outperformed previous protocols, and simulations were carried out on the UANET network using the OPNET simulator 14.5. The simulated architecture comprises an ad hoc network of UAVs equipped with IEEE 802.11 g cards and configured as illustrated in Table 3. In order to achieve a transmission area of 1000 m and match IEEE 802.11 g-designated long-range connectivity, the transmission power is set to 0.005 W, and receiver sensitivity is set to \(-95\) dBm. IEEE 802.11 g implementation was provided by the OPNET simulation software. The following three performance metrics are used: