Innovation in agriculture is more important than ever before. The agricultural industry is facing major challenges, from rising supplies costs and consumer preferences for transparency and sustainability. Traditional farming methods are unable to meet these new challenges, which can be handled by using modern farming techniques. Major innovations in this field have focused around areas such as robotics and automation, the Internet of Things (IoT), Wireless Sensor Networks (WSN), and Precision Agriculture (PA).

Precision agriculture (PA) also known as satellite agriculture, is the management of the farm that uses advanced technology to enhance crop cultivation. It includes, that the crop and soil receive the exact amount of inputs such as spraying, fertilizer, and insecticides. The main goal of PA is to ensure the profitability, sustainability, and protection of the environment.

Wireless sensor networks (WSN) are based on a large number of low-power sensor nodes whose goal is to transmit sensor data to the base station. A wireless network enables long-term data transmission that is difficult to obtain. Sensor nodes build up a network autonomously, without any external guidance or supervision. WSN is a cost-effective solution for wireless monitoring with improved reliability.

Long-Range wireless technologies

There are several low-power wireless standards like ZigBee, IEEE 802.15.4 and Bluetooth low energy (BLE) for higher data rates. For low ranges, these standards work fine, but for long-range, the reliable transmission is technology is necessary for data communication. SIGFOX and LoRaWAN are based on wireless communication protocol standards that allow transmitting at a lower data rate at distance up to 20 km known as Long Range Radio.

LoRa uses sub-gigahertz license-free frequency bands like 433 MHz, 868 MHz (Europe) and 915 MHz (North America). LoRa enables long-range low data rate transmissions with lower power consumption. LoRa technology consists of two main parts: LoRa, the physical layer, and LoRaWAN, the upper layers.

Sensors

WSN comprises of sensors, RF transceiver, microcontroller, battery and base station to transmit the data. Environmental factors such as temperature, moisture, and others have a significant effect on plant growth which can be monitor by using sensors. The sensor node deployed at a location senses these parameters of the environment and transmit the sensor data to the base station. Temperature and soil moisture are the most common sensors used in precision agriculture. Some other sensors can give more details about the present conditions of the environment, these include, CO2, Ammonia, LDR sensor, rain sensors, and pH sensors, etc.

A large amount of water is wasted in the irrigation process which must be controlled using advanced scientific techniques, soil moisture sensors can be a solution to reduce water wastage. The main feature of a WSN is self-organizing and self-healing. Once sensor nodes are deployed, the data will be automatically transmitted without any command or control.

Application of Environmental monitoring Sensors

In the field

Precision agriculture is the most promising domains where wireless sensor networks can deliver an optimal solution. Fields are instrumented with sensor nodes equipped with sensors for measuring air temperature, relative humidity, and soil moisture. The main objective is to indicate when the field is at risk of developing fungal diseases. These techniques in the field of agriculture can increase the yield of a crop by saving water from wasting and alert of diseases.

Long-Range wireless sensing allows field monitor wirelessly without the requirement of any carrier service. LoRa networks have ranges up to 20Km which makes it an ideal solution for monitoring fields at the lowest cost.

In Greenhouses

In the greenhouse, the objective of the implementation of temperature sensing is to evaluate the potential of saving heat energy in greenhouses. Accurate measurement of temperature is optional to achieve reliable and consistent results. Alongside it, the carbon dioxide and other gas sensors can be used to monitor the environment of the greenhouse and use it for maximum yield.

In the livestock

In livestock, the wireless measuring system keeps livestock healthier with minimum use of resources. It measures the temperature and pH level inside the cow’s rumen. The data is transmitted to an external receiver node. The information about the pH of a dairy cow can be helpful in the early detection of subacute ruminal acidosis.

In the woods

Monitoring the micro-climate in the forest is important, given the predicted climate change. Detailed knowledge of the chemical and biological status of soil makes a significant contribution to the monitoring of forest ecosystems. These long-term studies are key for the derivation of measures for forest management. Forest operation remains unaffected by the wireless transmission of sensor readings.

Wireless Sensor Networks (WSN) have developed at a fast pace in these last years and have been the major focuses of research in wireless technology. The developments of new wireless communication technologies and falling prices have enabled new uses for wireless sensor network devices. SigFox, LoRa, Weightless, and Ingenu are the most popular LPWA technologies. The main focus of LPWA is LoRa (Long Range), one of the most promising wide-area IoT technologies proposed by Semtech and further promoted by the LoRa Alliance.

With these emerging technologies, wireless monitoring techniques are becoming more efficient, advance and more affordable. Long-range wireless sensing technologies will revolutionize the agricultural industry and minimize the challenges it is facing these days.