# Evaluating the Feasibility of Intelligent Blind Road Junction V2I Deployments
## 4 Results
### Latency  
Latency is often viewed, in addition to reliability, as the dominant metric for safety-critical use cases and applications [65]. In the context of ITS, delayed packets can lead to  
\begin{table}
\begin{tabular}{c c c} \hline \hline
**Configuration** & **Data Type** & **Data Rate** \\ \hline \multirow{3}{*}{(Config. 1) Object Data} & Quiet Scene & 12.5 kbps \\  & Moderate Scene & 25 kbps \\  & Busy Scene & 50 kbps \\ \hline \multirow{3}{*}{(Config. 2) Sensor Data} & CCTV Camera & 8 Mbps \\  & Action Camera & 50 Mbps \\ \cline{1-1}  & Consumer Camera & 150 Mbps \\ \cline{1-1}  & Automotive Camera & 800 Mbps \\ \hline \hline \end{tabular}
\end{table}
Table 1: Data rates for measurement runs.  
an intelligent vehicle making a misinformed decision based on out-of-date information. Particularly in safety-critical ITS applications, this can lead to accidents, or in non-safety ITS applications can lead to decreases in traffic efficiency and fuel economy. Table 2 and Figure 6 present the latency performance statistics and distributions for each of the Sub-6 GHz and mmWave connectivity setups used to evaluate the network architectures of the IPS concept.  
Between the two connectivity setups, the mmWave setup achieved on average the lowest latencies, as shown by the quartiles in Table 2, with a minimum latency at 4.17 ms. However, the Sub-6 GHz setup displayed a higher degree of reliability and stability, resulting in a larger kurtosis (Sub-6 GHz: 182.65, mmWave: 82.43) and lower maximum latency (Sub-6 GHz: 279.91 ms, mmWave: 465.16 ms) compared to the mmWave setup. This stability difference between devices is highlighted by the distribution of outliers in Figure 6. Given that both connectivity setups use the same 5G NR core network, this apparent performance difference between the two connectivity setups is likely found in the wireless channel, where the shorter wavelengths of the mmWave setup provide a slight latency improvement. Additionally, as a consequence of these shorter wavelengths, the mmWave setup was slightly less reliable, again highlighted by the concentration of outliers around 100-200 ms in the box plot of Figure 6.  
Regarding Packet Delay Variation (PDV) or jitter, in Table 3 it is clear that the overall jitter of both devices is quite low with 95.75% (Sub-6 GHz) and 96.53% (mmWave) of packets having a jitter lower than 20 ms. While there is little difference in the median jitter of both devices (\(\sim\)0.44 ms), there is a notable difference in the maximum observed jitter, i.e., the worst case is 272.63 ms (Sub-6 GHz) and 457.42 ms (mmWave), indicating that the mmWave setup has slightly less reliability. This is further highlighted by the larger positive skew (Sub-6 GHz: 9.20, mmWave: 8.04) as can be seen from the empirical CDF curves in Figure 7, again indicating that the Sub-6 GHz setup has a higher degree of reliability than the mmWave setup.  
\begin{table}
\begin{tabular}{c c c c c c c c c c} \hline \hline
**Latency (ms)** & **Mean** & **StD.** & **Skew** & **Kurt.** & **IQR** & **Min.** & **25\%** & **50\%** & **75\%** & **Max.** \\ \hline Sub-6 GHz & 10.60 & 13.52 & 12.12 & 182.65 & 2.79 & 5.27 & 7.30 & 8.32 & 10.09 & 279.91 \\ mmWave & 12.04 & 24.36 & 8.15 & 82.43 & 2.64 & 4.17 & 6.95 & 7.93 & 9.59 & 465.16 \\ \hline \hline \end{tabular}
\end{table}
Table 2: Latency Performance Statistics.  
Figure 6: eCDF + marginal box plot of E2E latency performance distribution for Sub-6 GHz and mmWave connectivity setups (Sub-6 GHz: 8.32 ms, mmWave: 7.93 ms median latency).