# Experimental Study on LTE Mobile Network Performance Parameters for Controlled Drone Flights
## 3 Analysis of the Mobile Network Performance Parameters for UAV Application
The traffic requirements for UAV applications defined by [45] for all observed data-type categories are presented in Table 2. The most significant difference between the critical and non-critical communication requirements is reliability of \(10^{-5}\) referencing ARP4761, Guidelines and Methods for Conducting the Safety Assessment Process on Civil Airborne Systems and Equipment is an Aerospace Recommended Practice from SAE International. ARP4761 is needed to understand the evaluation framework of the critical safety data correlated to the aircraft. The FAA regulation-based framework discusses reliability requirements for data as well as safety-critical functionalities. According to the Low-Altitude Connected Drone Flight Safety Test Report (CAAC Information Centre/Flight Standard Department/Aircraft Airworthiness Certification Department, 2018), the requirements on communication link UL/DL specifications for drone flight safety link description rate are characterized in Table 3. \begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**Parameter**} & \multirow{2}{*}{**Direction**} & \multirow{2}{*}{**Protocol**} & \multirow{2}{*}{**Bandwidth** **(kpps)**} & \multicolumn{2}{c}{**Round-Trip**} & \multirow{2}{*}{**Reliability** **(PLER)**} & \multirow{2}{*}{**Priority**} \\  & & & & & **(m)** & \\ \hline Non-critical communication & UL/DL & TCP & 35 & 500 & \(10^{-3}\) & System design \\ Critical Communication & UL/DL & TCP & 35 & 500 & \(10^{-5}\) & Very high \\ Video and image streaming & UL & UDP & 4096 & 500 & \(10^{-3}\) & System design \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Traffic requirements for UAV applications [45]. Nevertheless, to maintain the relatively high credibility of aerial connections, 3 GPP (the mobile broadband standard) states C2 requirements of packet delivery conditions, meaning that the packets ought to be delivered to the receiver within the set delay budget (50 ms and 99.9% reliability) in all of such scenarios. As for the C2 link and its throughput, 3 GPP references 100 kbps, is thus evaluated as relatively low compared to other types of applications within the cellular field. Additionally, drones and their operational systems can also have other types of active applications that utilize or require radio communication links. For instance, live-stream videos that provide relatively high-quality images can also require high throughput connection links while ensuring the operation of the drone [47]. While the KPIs of DL/UL and latency go from requirement to reliable data transfer, these parameters for the network are secondary. These parameters depend on the overall network performance characterized by strength, quality, and interference parameters: RSRP--network strength, RSRQ--cell quality, and SINR--interference. _RSRQ_ (reference signal received quality) is a parameter that describes the ratio between _RSRP_ (reference signal received power) and _RSSI_ (received signal strength indicator) and is an overall indicator of the quality of signal received by the receiver. It is calculated with the following equation. \[RSRQ=\frac{N\times RSRP}{RSSI} \tag{1}\]  
In this equation, \(N\) represents the number of resource blocks. _RSRP_ is the power of the connection between the node on the BTS and UE. _SINR_ is the ratio between signal power and the power of noise and interference. Just like RSRQ, it is a measurement of signal quality, but unlike _RSRQ_, which only considers the strength of the signal, it also shows the strength of noise. It is calculated as follows. \[SINR=\frac{P_{signal}}{P_{noise}+P_{interference}} \tag{2}\]  
where \(P_{signal}\) is the signal power