Irrigation and automation - a look to the future

Take home messages

• Combining wireless sensors, computer modelling and automation technologies can help you develop your own customised irrigation water management system.
• Don’t let the availability of connectivity limit your farming practice - create your own internet connectivity if necessary.

Background

The irrigation sector has faced many challenges over the past decade including severe and prolonged drought, reduced water availability and ongoing reform of government water policies. The agricultural sector is the largest consumer of water, consuming 65% of total water use in Australia (Mushtaq, 2011). Growers are under pressure to increase water use efficiency whilst maintaining or increasing yields to meet market needs. The adoption of new technology can assist growers in the management of their irrigation systems to not only use water more efficiently, but also save time and labour costs. Connectivity is the limiting factor in the adoption of certain new technology in farming, and optimising the speed and coverage of your internet service will provide the best access to information and services as well as allowing the adoption of new technologies.

Practical examples of technology available for irrigation

Installation of systems such as centre-pivot or drip irrigation involves significant initial capital investment, maintenance and replacement costs. Using technology and automation can increase efficiency of the equipment and safeguard damage to equipment.

Irrigation water management helps irrigators to determine how much water their crop has used and how long they need to run their pump or drip system each day using the latest in remote sensing techniques and mobile phone based delivery services. Better controlled water application (both in terms of volume and frequency) helps ensure timely application of water in response to crop requirements. Automation technology, allowing remote control of pumps and irrigation equipment can significantly reduce time and labour costs.

The use of soil moisture probes at various depths in different location enable detection of under or over watering and assist in making better farm decisions. Alarms can also be setup for automation and control and notification.

Weather station monitoring technology (including temperature, rainfall, sunlight, humidity, etc.), can assist in irrigation software applications for calculating water loss through evapotranspiration and other measurements.

Wireless transmitters for water level monitoring for dams, tanks and canals can assist in better management of your water resources.

Satellite/UAV imagery is a technology than can be used to monitor plant canopy size and response to treatments with water and chemicals.

The use of wireless monitoring of water pressure and flow can help protect equipment, detect blockages and leaks in the irrigation system and also safeguard against water damage to the crop.

Technology can also be used in engine management, both for control and engine monitoring. Dieseldog is an Australian company that manufactures an engine management system that can reduce fuel costs and prolong engine life by monitoring rpm, engine temp, voltage, oil pressure and coolant levels of any engine or generator. Each engine can be monitored and controlled from a smart phone or control panel.

What opportunities does good connectivity bring?

Good connectivity allows the adoption of technology such as remote monitoring and reporting of data such as soil moisture probes, temperature and rainfall weather data, dam and water storage level monitoring, monitoring crop responses via satellite imagery or UAV analysis, as well as water level/flow/pressure monitoring and engine control and management.

For optimal results, a good internet connection in the home/office is required in addition to a mobile internet connection such as a smart phone or tablet.

Choose the best internet connection available to you

The roll out of the National Broadband Network (NBN) is starting to address connectivity issues, and in rural areas you are most likely to be offered a wireless solution such as Fixed Wireless or satellite broadband rather than optical fibre when NBN comes to your area. To check whether NBN is available in your area and the type of NBN connection that is available to you, consult the NBN Co website.

Choose the best internet connection available to you that meets your current and likely future needs. Not all types of internet connections are available to all areas, the reliability and speed of the connection (not just the cost) should be considered when comparing options. The speed of an internet connection is measured in Megabits per second (Mbps) and often download speeds are higher than upload speeds.

I would rank the internet connection options in the following order or preference:

1. NBN Fibre. This is the fastest most reliable connection available, with download speeds of up to 100Mbps with future plans to upgrade to speeds of 1000Mbps. This service is likely to only be available in major towns, with coverage increasing over time. However, it is unlikely to ever reach everyone in Australia.
2. ADSL. This type of internet connection is generally only available within 12km of an exchange or mux, so it is not typically available on-farm in Australia. If you have an existing ADSL connection, hold onto it until NBN Fibre becomes available, as new ADSL connections are becoming increasingly hard to source as each exchange/mux has a limited number of ports available for this service. The connection speed for ADSL is generally less than 24Mbps, so it is definitely worthwhile upgrading to NBN Fibre when it becomes available.
3. Fixed Wireless / WiMax. This type of internet connection uses a wireless signal that travels from a transmission tower to an external antenna mounted to your home or office and connection is via a modem. To receive this service you need to be in line of sight and within about 20km of the nearest transmission tower. NBN Co offers a fixed wireless service to some rural areas, with coverage increasing as the NBN continues to roll out. If you cannot get NBN Fibre and NBN Fixed Wireless becomes available in your area, sign up as soon as possible as there are a limited number of connections available for each tower. There are also non-NBN suppliers of fixed wireless connections (eg. Countrytell and Internode). Fixed wireless internet connections offer connection speeds of up to 25/5Mbps and offer a more reliable service than 3G/4G mobile broadband. Fixed wireless internet connection also has the advantage of not sharing bandwidth with mobile phone users. Ask providers about non-standard installations, as there may be a point on the property with a line of site to a transmitter and the signal can then be relayed to the house/office.
4. 3G and 4G mobile broadband. This type of internet connection uses the mobile phone network, with modem devices containing a mobile phone sim card. To access this service, you need at least one bar of mobile signal. The use of external antennas on your mobile broadband modem will improve the quality and strength of the incoming signal and result in faster internet connection speeds. The signal strength is affected by weather conditions, terrain, distance from the nearest transmission tower and the number of other users on the network. 4G mobile broadband has connection speeds of up to 40Mbps, but is typically less than 20Mbps in rural areas. 3G mobile broadband has connection speeds of up to 20Mbps, but is typically less than 8Mbps in rural areas.
5. Satellite Broadband. The current satellite broadband system is at capacity, with no new connections currently available. Consequently, if none of the above connection types are available to you and you have an existing satellite service, hold on to it until other options become available. NBN Co is expected to release a new satellite broadband service in 2015. Satellite broadband is the last option of the established internet connection types as it tends to be much slower than the above services, has smaller download limits and tends to be more costly. In addition, the nature of the way the signals are sent and received via satellite service (in packets) results in latency issues (sometimes referred to as lag) which can present problems with some software applications for monitoring devices as well as affecting performance of internet services such as video playback.
6. Setup your own point to point wireless link. Setting up your own high speed wireless internet connection from a Telco tower is possible using systems such as Ubiquiti Airmax, which use either antennas or dishes to establish a point to point link to the internet with access speeds of up to 300Mbps. To establish such a link, you will need a tower to mount the antenna/dish on your property in a location which has a line of sight to the Telco tower which you are utilising for transmission. The tower site will also need to have power available, but the power requirements are low and can be met through the use of solar panels if necessary. Using antennas, a point to point system has a range of approximately 20km but this can be increased up to 60km by using dishes instead of antennas. The installation of this service will require a professional installer and negotiations with a Telco for the incoming signal to the transmitter.

Optimise your mobile phone reception

Having a good internet connection in the office is important, but you will also need mobile internet access for alarms, real time monitoring in the paddock as well as automation control away from the office. The smart phone or tablet are the most common devices for this purpose, and internet connectivity can be established through either the 3G/4G mobile network or using WiFi.

Selection of a mobile phone carrier will establish your base level of phone reception. The coverage of the two major networks in Australia; Telstra and Optus differ in rural areas. Before selecting a mobile phone carrier, check the coverage in your area using online coverage maps. When examining the coverage maps pay close attention to the type of signal expected in your location – 3G vs 4G, as well as the expected data rates for internet access using the mobile network, and areas which will likely need an external antenna for optimal performance.

The selection of your brand and model of smart phone can also influence your mobile phone reception as the design and performance of the phone’s internal antenna system varies between handsets. Telstra have a “blue tick” system for recommending handsets most suitable for use in rural areas, but there is also a tool called “field test mode” which will enable you to compare the signal level of various phones. The field test mode gives a reading in decibels (dB) of the phone signal for your current location, and is more accurate than comparing ‘bars’ of service (Uber Signal, 2013). For an iPhone, the field test mode can be accessed by selecting *3001#12345#* on the phone number keypad and then pressing send. You will see the ‘bars’ of service replaced with a signal reading. In general, the lower the signal reading number, the better the signal. For Android users and for further information on interpreting the signal reading, check online resources by searching ‘field test mode’ and the model of your phone.

The use of cradles and car antennas for mobile phones will improve the quality and reception of voice calls, but not significantly increase the performance of data and internet reception. This is because voice and data operate on different frequencies, and the car antennas only amplify the voice signals and not the data.

Optimise internet connectivity in the home/office through the use of antennas and networking

For 3G/4G mobile broadband, the internet connection can be optimised through the use of external antennas. The antennas used should be designed for 3G and 4G data frequencies and NOT for a car antenna (Table1). For best results, where the mobile broadband device hast two antenna connections, use two external antennas. The device will work with only one antenna, but using two will result in higher data rates, and in the case of 4G LTE the performance can be doubled.

There are a range of antennas available for 3G/4G mobile broadband, including yagis, log periodic, parabolic and wide band MIMO antennas with gains between 9 and 21dB. Unlike car antennas which are omni directional, external antennas for 3G/4G mobile broadband tend to be directional and need to point to the nearest mobile phone tower for your service provider. In general, the higher you mount the antenna the better the signal. You can use the inbuilt ‘field test mode’ of your smart phone to help locate the best position for mounting your external antenna. Do not split the signal from an external antenna to multiple devices. By doing so, you would be halving your signal and if the other devices (such as Cel-Fi) use a different frequency you will only reduce the performance of both devices.

Selecting the right type of cable between the antenna and your device is critical. You need communications grade cable (RG12 or Cat 5) rather than TV cable (RG6) and the fittings should be high quality. Most antenna suppliers offer a cable manufacturing service, with the correct fittings and cable cut to a custom length.

Most 4G mobile broadband modems allow 5-10 WiFi connections directly to the modem device to achieve internet access for additional WiFi enabled devices. The use of a matching cradle and a wireless router will allow you to share the mobile broadband connection with more than 10 devices and also via Ethernet connections.

Adding networking, especially the use of a wireless router with any other type of internet connection will allow you to share your internet connection with other users and devices in the home or office. When selecting a wireless router, choose one with the latest protocol – 802.11AC, as this latest protocol offers a 2.4 and 5GHz transmission frequencies and larger bandwidths for channels which therefore allows higher data transfer rates. For example, 802.11g has a maximum data rate of 54Mbps, 802.11n has a maximum data rate of 150Mbps while 802.11AC has a maximum data rate of 866Mbps. The range (transmission distance) is also better for later WiFi protocols (up to 50m inside vs up to 20m) (Angell, 2014).

WiFi and wireless networking capabilities

If you do not have 3G or 4G mobile coverage on your property, then you will need to create your own internet connectivity through extended networking and WiFi technology.

WiFi is a technology that allows a device to exchange data or connect to the internet wirelessly using 2.4GHz and 5GHz radio waves. The range, or transmission distance, of WiFi indoors is typically less than 50m and depends on the building construction and the number of internal walls. To optimise WiFi coverage inside a building, WiFi boosters, or WiFi range extenders can be purchased at a very low cost (less than $100). These plug into the power outlet and amplify the WiFi signal increasing coverage from that point. It is important to match the protocol of the WiFi booster to that of your Wireless router. For example, if you have an 802.11n wireless router, then you must purchase an 802.11n WiFi booster.

To transmit data and share internet access outdoors (over a distance of up to 5 km (needs line of site)) using WiFi technology, Netcomm NP730 outdoor wireless access point (retails at less than $500) can be used. Note however, the data transmission speed significantly reduces the further you move away from the access point. For this reason, it is not advisable to install a series of access points to create extended networks over distances of more than 5km.

Creating your own connectivity – extended networking

If necessary, it is possible to establish your own point to point internet connection from a Telco tower, and share the cost of the infrastructure setup with small groups of farmers or communities.

Extended networking over distances of more than 5km is best managed with either point-to-point or point-to-multipoint wireless networking solutions. These systems will allow you to set up your own internet service in collaboration with a Telco tower, or to share the internet connection across your property or even share an internet connection with multiple properties.

The topology of more complex wireless networks can be categorised as follows (Wndw.net, 2007):

• Point-to-point. These links can be used to establish an internet connection or extend a network over a long distance (20 – 60km). This was discussed above in reference to setting up your own internet connection.
• Point-to-Multipoint. This uses either an omni-directional or sector (90 -120degree) transmitter with multiple receiving antennas. Think of this type of network as an ‘access point’ with multiple ‘clients’. These systems generally operate over medium distances (0-10km). This system is suitable for sharing internet connection across a property, or with multiple properties.
• Multipoint to Multipoint. This system allows any node of a network to communicate with another, also known as an ad-hoc or mesh network. These systems are considerably more complex, and while easy to add more nodes, they can be difficult to tune and are much more costly to install.

Due to the complexity of the systems, the installation and configuration of a point-to-point or point-to-multipoint network is best left to the professionals. However, Ubiquiti Airmax wireless networking systems have equipment available for sale in Australia to implement either of these systems.

The cost of setting up your own internet infrastructure (either creating your own internet connection or creating a property wide WiFi network) may seem high, but farmers need to consider the cost of being left behind and the long term savings that can be achieved through streamlining tasks and using automation, which will then allow for more time in the field and less time in the office. To reduce costs, consider forming your own group or community to share an internet connection and better manage the initial cost of the infrastructure.

Conclusion

ICT for communications on and off the paddock is the critical component in successfully integrating new technologies in your irrigation system.

Good connectivity allows the adoption of technology such as remote monitoring and reporting of data such as soil moisture probes, temperature and rainfall weather data, dam and water storage level monitoring, monitoring crop responses via satellite imagery or UAV analysis, as well as water level/flow/pressure monitoring and engine control and management. If 3G/4G mobile coverage cannot provide internet access then extended networking and wireless communications systems are necessary to create this connectivity.

Resources

The ‘Digital Ready Grain Growers’ google+ community houses a number of connectivity fact sheets that will assist you in getting your farm digital ready.

For general information and technical specifications on antennas, the following website is a good starting point: Telco Antennas website

References

John W. Hornbuckle, Nicholas J. Car, Evan W. Christen (2009). Thomas-M. Stein and Bill Williamson Irrigation water management by satellite and SMS - A utilisation framework. Retrieved from Article link

Shahbaz Mushtaq and Tek N. Maraseni (2011). Technological change in the Australian irrigation industry: implications for future resource management and policy development. Retrieved from Article link

Roberts, K. and McIntosh,G. (2012). Use of mobile devices in extension and agricultural production- a case study. Retrieved from Article link

Stocks, C. (2011). Communication with farmers- a Nuffield Farming Scholarships report. Retrieved from Article link

Australian Communications and Media Authority (2014). Digital dividend auction- results. Retrieved from Article link

David Angell , Intel (2014). Next-Gen 802.11ac WiFi for dummies. Retrieved from Article link

Wndw.net, 2007. Wireless Networking in the Developing World 2nd Edition. A practical guide to planning and building low-cost telecommunications infrastructure

Contact details

Ian Ware
APA Sound
PO BOX 24 Cooma NSW 2630
(02) 6452 2555
ianware@apasound.com.au