# Water IoT Monitoring System for Aquaponics Health and Fishery Applications
## 4 Proposed IoT System Architecture for Aquaponics Monitoring  
The proposal and development of an IoT system architecture for monitoring aquaponics health is very useful for the fishery farms industry as the automation in the care and exploitation of fish allows for an improvement in production. Figure 3 shows the proposed IoT system architecture for aquaponics monitoring. This system is comprised of a farmhouse which houses a monitor, WiFi link (or wireless technology), keyboard, mouse, and gateway box. The system also considers a growing bed; a 1 km\({}^{2}\) wireless link; a sensor box with a set of sensors deployed in the field according to the analysis in Section 3.1, where different types of field sensors will be deployed in fishponds; a sump; and filters to monitor appropriate metrics. The farmhouse (as explained in Section 6) contains a gateway sensor, which forwards all the metrics from LoRa technology to other technologies and a monitoring station, which allows the first visualisation and control of the metrics. The gateway sensor also allows the connection to other infrastructures through WiFi or LTE-M/NB-IoT. This infrastructure allows the connection to the CORE and Cloud and the monitoring from a remote/house station. LoRaWAN is the specification for Low-Power Wide-Area Networks (LPWAN) in Low Radiation (LoRa) communications. From the LoRa protocol, LoRaWAN is a point-to-multipoint network layer protocol, full duplex, and with the best LoRa features, i.e. low-power, extending battery duration and quality of service (with three modes), and uses FSK modulation. LoRa-based technology is able to achieve long ranges. \begin{table}
\begin{tabular}{l l l l l l l} \hline \hline  & **Meas. Range** & **Resolution** & **Accuracy** & **Response Time** & **Data Protoc.** & **Function.Temp** \\ \hline Temp (AtlasSci.) & \(-\)126.000–1254 °C & 0.001 °C & \(\pm\)(0.1 + 0.002 ×C) & 1 read per 420 ms & UART/12C & \(-\)40 °C to 85 °C \\  & 0.5 to 500 ppm & & Potential drift (in & & & (Typ. 25 °C) \\ \(NO_{2}^{-}\) (Nico2000) & (10\({}^{-5}\) Mol to & 0.5 ppm & 1000 ppm): & \(<\)10 s & I2C & 0 °C to 50 °C \\  & 0.01 Mol) & & \(<\)3 mV/day (8 h) & & & \\  & 0.3 to 6200 ppm & & Potential drift (in & & & \\ \(NO_{3}^{-}\) (Nico2000) & (5 \(\times\) 10\({}^{-6}\) Mol to & 0.3 ppm & 1000 ppm): & \(<\)10 s & I2C & 0 °C to 50 °C \\  & 0.1 Mol) & & \(<\)3 mV/day (8 h) & & & \\  & 0.03 to 1800 ppm & & Potential drift (in & & & \\ \(NH_{4}^{+}\) (Nico2000) & (2 \(\times\) 10\({}^{-6}\) Mol to & 0.03 ppm & 1000 ppm): & \(<\)10 s & I2C & 0 °C to 50 °C \\  & 0.1 Mol) & & \(<\)3 mV/day (8 h) & & & \\ \hline \hline \end{tabular}
\end{table} 
Table 4: _Cont_. Figure 3: Proposed architecture for our Aquaponics Monitoring System. LTE-M (or LTE-MTC (Machine-Type Communication)), including eMTC (enhanced Machine-Type Communication), is a low-power wide-area network (LPWAN) radio technology standard developed by 3 GPP to enable a wide range of cellular devices and services (specifically for machine-to-machine and Internet of Things applications). The specification for eMTC (LTE Cat M1) was frozen in 3 GPP Release 13 (LTE Advanced Pro) in June 2016. NB-IoT is also an LPWAN protocol, and it is a radio technology standard developed by 3 GPP to enable high-end services for mobile devices. Previously, the 3 GPP Release 13 (LTE Advanced Pro) specification was used until June 2016. NB-IoT uses an extension of the standard LTE network but limits bandwidth to a single 200 kHz band. It uses OFDM modulation for communications with few connections between devices and uses SC-FDMA for communications with more connections between devices. The advantage of LTE-M over NB-IoT is its comparatively higher data rate, mobility, and voice over the network, but it requires more bandwidth and is more costly. Compared to an LTE Release 12 Cat-0 modem, an LTE-M modem is claimed to be 80% less expensive, supports up to 18 dB better coverage, and has a battery lifetime that can last up to several years.