With the advancement in technology and as the internet of things (IoT) grows, the market for bandwidth is rising. Among the emerging wireless technologies, LoRa is one that you can use in a wide range of industries. It is one of the best fits for myriad markets. By offering long-range wireless connectivity and low power consumption, long-range (LoRa) technology is expanding the reach of the Internet of Things (IoT).
So, it is clear that LoRa will play a massive role in the IoT industry. Since IoT has a significant impact as an enabler technology in the agricultural sector, it is possible to overcome several technical challenges with wireless systems in precision agriculture, especially in urban areas. These challenges include cost-effectiveness, the need for long-range communication, high network capacity, and long battery life.
The LoRaWAN technology is already being used in irrigation systems. For instance, Usmonov et al. presented a wireless irrigation control system based on the LoRaWAN technology. So, it is not a challenge to understand new wireless technology and choose the best solution for the application. So, here in this article, we will explore how to design a wireless system to control drip irrigation with LoRa. Stick around to know more about it.
System Architecture of LoRa
LoRa refers to the physical (PHY) layer and the wireless modulation that creates long-range links for communication. It depends on the spread spectrum technology. So, the urban LoRa technology portals can transmit up to 4 kilometers, and rural LoRa technology portals can transmit up to 16 kilometers.
It’s a network protocol standardized by the LoRa Alliance. This technology uses secure localization services, mobility, and bidirectional communication. Moreover, LoRaWAN uses the LoRa protocol and is a Layer Protocol (MAC) that allows a complete network to function.
The architecture of LoRaWAN is layered architecture. As a result, the gateway can relay data from the central network server to the end devices. Here is an example of an activity and monitoring architecture system based on LoRa. The system consists of four main parts, cloud, LoRa Gateway, LoRa Device, and mobile application.
LoRa Wireless System to Control Drip Irrigation
Over the last few decades, drip irrigation systems have become increasingly popular. But, as they become more widespread, manual control becomes increasingly difficult. In that regard, setting up a wireless actuator network is one way to overcome this problem. The drip irrigation system is a method used to conserve water usage in agriculture.
This process involves applying water drop by drop to the crop roots continuously. And the control of this process relies on the remote operation of actuators. So, before designing a wireless system, it is critical to consider the following points.
- Batteries must have a minimum lifespan of two years. And on average, wireless nodes receive commands four times a day. Also, it has typical alkaline, four D-size, and non-rechargeable batteries installed.
- There must be a maximum of 1000 nodes in one wireless system.
- The system can extend its range to at least 2 km with a single transmission. And it has extendibility by deploying repeaters.
- Easy setup and low cost are plus points.
- To individually control each node to reduce the cost for actuators, the system should have more than four actuators.
So, it is necessary to choose the entire specifications cautiously before designing the system to meet the requirements. Hence for the system setup, other technologies also need to be examined for comparison. Furthermore, to fully automate the drip irrigation system, soil sensors need to be installed across the field, and measurement data should be collected and analyzed before the system makes decisions automatically. Therefore, any remote control system for drip irrigation must have the ability to control the actuators as one of its basic features.
Design Wireless System using LoRa
The LoRaWAN protocol is the most effective technology to control drip irrigation due to the small amount of data it exchanges. With its highest radio link budget and the best balance of cost, power, and range, this is the best radio link to use in the drip irrigation system. However, while designing the LoRa network, there are four elements to keep in mind.
- The end nodes of the LoRa wireless system are responsible for collecting sensor data and transmitting/receiving it. Generally, they run on batteries and are remotely connected.
- Gateways are a seamless bridge between the network servers and the end nodes. The end nodes connect to the gateway using LoRaWAN, and the gateway connects to the networks using high-bandwidth networks such as Ethernet, Wi-Fi, or cellular.
- Multiple gateways are connected to a network server. That way, data is gathered from the gateways, duplicate messages are filtered out, gateways are picked to respond to messages from end nodes, and data rates are adapted to extend battery life.
- And lastly, end nodes collect data from the application server and control their actions.
In addition, it is critical that the wireless nodes can control solenoid actuators through power-efficient driver blocks. Since we have chosen LoRa for the drip irrigation wireless system, its module is best for radio communication. It consists of all necessary radio components with the “radio frequency” (RF) circuitry and a LoRaWAN stack. So, in that way, it helps accelerate the LoRaWAN development for end devices.
In the case of changes in certification specifications or component replacements, the module manufacturer is responsible for taking care of them since the module manufacturer implements both RF development and certification. Thus, it saves recertification costs and development time for end-device manufacturing. A highly certified LoRa module simplifies the design process and allows end-node developers to release their products quicker and differentiate products from others.
In the field of agriculture, using wireless systems entails many technical challenges. But, over time, many protocols and technologies emerged to overcome such issues. And one of them is an exclusive modulation technology, LoRa. It is widely adopted and incorporated into many systems, including small makers like Arduino computers.
Accordingly, LoRa wireless system is suitable for specialist applications and large-scale manufacturing like a drip irrigation system. LoRa wireless system provides wireless control to the overall irrigation system, including soil temperature and moisture, line flow and pressure, etc.
In addition, Arshon Technology has also developed many projects, including GPS and USB tracking systems and designing and manufacturing gateways with the “LoRa Technology.” Here is the list of some of the Arshon Technology projects using the LoRa network, including USB Multi-RF gateway for wireless sensor network and LoRa offline GPS tracking systems. Also, Arshon Technology considers using the LoRa network in other fields in various applications. So, the devices could communicate efficiently and with low power consumption over long distances.
Author: Eli(Elnaz) Sadafi, IoT design engineer @ Arshon technology.