# Communication Infrastructure Design for Reliable UAV Operations in Air Mobility Corridors
## 4 Discussion
### Resource-Reliability Trade-Off for UAV Communication Strategies  
The evaluation of different UAV communication strategies reveals a fundamental trade-off between system reliability and resource efficiency, as illustrated in Figure 22. This trade-off represents one of the key considerations when designing air mobility corridors with the appropriate level of communication redundancy. Figure 21: Channel unavailability for different strategies. As shown in the left panel of Figure 22, the overall system reliability (\(A\)) increases substantially when moving from Strategy 1 to Strategy 2, with more modest improvements when advancing to Strategy 3 and Strategy 4. However, these reliability gains come at varying resource costs, with Strategy 4 requiring four times the infrastructure of Strategy 1. The right panel of the Figure 22 reveals a more nuanced perspective by examining resource efficiency. The efficiency is calculated by dividing the system reliability (\(A\)) by the number of stations required for each strategy. Here, Strategy 3 emerges as the most efficient (0.065), followed closely by Strategy 1 (0.060), while Strategy 4 shows the lowest efficiency (0.025) despite its superior absolute reliability. This indicates that Strategy 3, with its alternating duplication approach, optimizes the balance between reliability and resource utilization. These findings suggest that the selection of an appropriate communication strategy should be context dependent. For critical UAV operations where safety is paramount and resource constraints are secondary (such as emergency medical transport), Strategy 4 near-perfect reliability may justify its higher resource requirements. Conversely, for commercial applications with moderate reliability requirements but significant cost sensitivity, Strategy 3 offers the most favorable balance. In resource-limited environments or for non-critical operations, Strategy 1 might provide a minimally acceptable reliability level while conserving infrastructure. The relationship between communication load \(\rho\) and these efficiency metrics further complicates the selection process, as higher loads tend to reduce the relative advantages of more complex strategies. System designers must, therefore, consider not only the current communication demands but also anticipated future traffic increases when selecting the optimal strategy for long-term deployment. To systematically explore how redundancy levels can be optimized through sensitivity analysis, this section examines the parametric relationships between key system parameters and the effectiveness of different deployment strategies. The analysis focuses on identifying optimal redundancy configurations under varying operational conditions and constraints. The sensitivity of system availability, \(A\), to key parameters is quantified using normalized partial derivatives with respect to the failure rate, \(\lambda\), the repair rate, \(\mu\), and the  
Figure 22: Comparative analysis of reliability metrics across UAV communication strategies (for \(\rho=0.05\)). traffic intensity, \(\rho\). For each deployment strategy, \(k\), the sensitivity coefficients are defined as follows:  
\[S_{\lambda}^{(k)}=\left(\frac{\partial A^{(k)}}{\partial\lambda}\right)\frac{ \lambda}{A^{(k)}},\quad S_{\mu}^{(k)}=\left(\frac{\partial A^{(k)}}{\partial \mu}\right)\frac{\mu}{A^{(k)}},\quad\quad S_{\rho}^{(k)}=\left(\frac{\partial A ^{(k)}}{\partial\rho}\right)\frac{\rho}{A^{(k)}} \tag{15}\]  
This normalized form allows the direct comparison of sensitivity across parameters with different units and magnitudes. Figure 23 illustrates the sensitivity analysis results for the four deployment strategies, showing how system availability responds to a 10% variation in each parameter. Strategy 1 exhibits the highest sensitivity to failure rate changes \(S_{\lambda}^{1}=-2.34\), indicating that single-station coverage is highly vulnerable to equipment failures.