# Deployment Strategy of Shore-Based Cooperative Units for the Internet of Inland Vessels
## 4 Case Study
### Deployment Strategy Examples  
The density of ships is 10 ships/km and the average speed is 12 knots in a channel with a length of 10 km and a width of 70 m. The terminal has different requirements for signal reception sensitivity and transmission quality due to the different operating frequency bands and transmission technologies of mobile networks and WiFi. The signal reception sensitivity of ship communication equipment for mobile networks is \(-100\) dBm; the signal reception sensitivity for WiFi networks is \(-80\) dBm [29]; the vertical distance between the deployment location of the base station and the edge of the channel is 50 m; the length of the same frequency signal overlap switching band is 16.5 m.  
For the above scenarios, suitable mobile base stations and WiFi base stations were selected to cover heterogeneous two-layer communication networks. According to the deployment method above-mentioned, the planning and selection of base stations were considered from the following two aspects. Types of base stations: Following the M type (M = 9) of base stations (Table 3) should be considered to plan the communication coverage of autonomous transportation systems on inland rivers. Figure 5: System communication throughput. Figure 6: PDF and CDF curves of the system data throughput. There are a total of 625 combinations for each type of base station based on the total bandwidth, transmission power, base-station height, and antenna type. Signals in the low-frequency band propagate farther and cover a wider area with stronger penetrability in the case of the same bandwidth. Therefore, they are subject to more demand and competition. For bandwidth resources of the same size, the price of the higher frequency band is usually lower than that of the lower frequency band. Moreover, antenna prices are affected by the communication frequency band and communication technology. Even if the same type of configuration combination is selected for different types of base stations, the price corresponding to a single station is different. The transmission power of ships can be adjusted adaptively, so the downlink can be considered when making the link coverage budget. According to the link coverage budget equation and the corresponding propagation model of various types of base stations, the base-station coverage radius of the \(k^{th}\) configuration in the \(m^{th}\) type can be obtained. Then, the deployment spacing can be obtained. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multicolumn{2}{c}{**Base-Station**} & \multicolumn{4}{c}{**Optional Types**} \\ \hline Total bandwidth (MHz) & 20 & 40 & 60 & 80 & 100 \\ Transmit power (W) & 40 & 45 & 50 & 55 & 60 \\ Tower height (m) & 30 & 35 & 40 & 45 & 50 \\ Antenna type & 9 dBi direction & 11 dBi direction & 13 dBi direction & 17 dBi direction & 20 dBi direction \\ \hline \hline \end{tabular}
\end{table} 
Table 4: Available configurations of mobile communication base stations. \begin{table}
\begin{tabular}{c c c c} \hline \hline \multicolumn{2}{c}{**Base Station Type**} & \multicolumn{2}{c}{**Spectral Efficiency (bps/Hz)**} \\ \cline{2-4}
**Type Number** & **Communication Technology** & **Operating Frequency Band (GHz)** & **Spectral Efficiency (bps/Hz)** \\ \hline
1 & 4G & 1.9 & 3 \\
2 & 4G & 2.3 & 3 \\
3 & 4G & 2.5 & 3 \\
4 & 5G & 2.6 & 5 \\
5 & 5G & 3.5 & 5 \\
6 & 5G & 4.9 & 5 \\
7 & WiFi5 & 5 & 3.5 \\
8 & WiFi6 & 2.4 & 4.8 \\
9 & WiFi6 & 5 & 4.8 \\ \hline \hline \end{tabular}
\end{table} 
Table 3: Types of base stations for selection. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multicolumn{2}{c}{**Base-Station**} & \multicolumn{4}{c}{**Optional Types**} \\ \hline Total bandwidth (MHz) & 20 & 40 & 60 & 80 & 100 \\ Transmit power (W) & 40 & 45 & 50 & 55 & 60 \\ Tower height (m) & 30 & 35 & 40 & 45 & 50 \\ Antenna type & 9 dBi direction & 11 dBi direction & 13 dBi direction & 17 dBi direction & 20 dBi direction \\ \hline \hline \end{tabular}
\end{table} 
Table 5: Available configurations for WiFi base stations.