Author: Support

Using iBeacon for Sensing in Viticulture

There’s new research by Sotirios Kontogiannis and Christodoulos Asiminidis of University of Ioannina, Greece on A Proposed Low-Cost Viticulture Stress Framework for Table Grape Varieties.

The system automatically monitors vine stress to provide real-time surveillance and alerts. It identifies specific areas for irrigation, thereby saving water, energy and time.

The Bluetooth iBeacon protocol is used to relay temperature, humidity, UV levels and soil moisture levels. The authors modified the standard iBeacon protocol, using the existing iBeacon minor and major fields to encode the telemetry data.

View Sensor Beacons

Differences in Beacon System on a Chip (SoC)

You can find the processor chip in the specification section of our beacon descriptions. Most people don’t know what this means or implies. This article will help you make a more informed choice.

nRF51822 in a round beacon

There are currently three main chip families from Texas Instruments (CC25xx, CC26xx), Dialog Semiconductor (DAxxxx) and Nordic Semiconductor (nRF51xxx and nRF52xxx). These chip manufacturers publish standard electronic circuits and software SDKs that beacon OEMs use for their beacons. Hence, most beacons, within a chip family, have very similar designs. Small differences in implementation of board layout in areas such as the power supply, grounding, terminations, connectors and the antenna can cause electrical differences that can cause loss of power.

The strength of the beacon radio signal is affected more by the quality of the beacon implementation, particularly the antenna, rather than the choice of chip. This is also evident in real world tests. We have performed RSSI strength and stability tests on the beacons we sell and haven’t yet found any correlation between signal strength and chip family.

The choice of SoC affects battery use. Newer chip families such as the Nordic nRF52 (as opposed to nRF51) and Texas Instruments CC2640 (as opposed to CC2541) are more power efficient.

Most beacon SoCs transmit up to +4dBm output power for a longer range. A few such as the nRF52840 and CC2640RF can be set to higher output power of +8dBm and +5dBM respectively, with a consequent reduction of battery life. If you are looking for longer range, it’s more usual to use a long range beacon with an additional output amplifier chip.

The newer SoCs have much more memory. This isn’t used for most beacons except for those that store data.

The use of standard SoC manufacturer designs and software means that all beacons work well, adhere to Bluetooth standards and compatibility is never a problem.

Can Beacons Store Data?

Beacons don’t generally need to store data because they are just sending out their unique id. However, sensor beacons do sense values over time that you might want to collect later via, for example, an app coming close to the beacon. Specialist devices such as social distancing beacons need to store close contacts for later collection.

Beacons use a System on a Chip (SoC), such as the Nordic nRF51, that includes memory. Most of the memory is used for the internal functioning of the beacon. Newer versions of SoC, for example the Nordic nRF52, have more memory that allows data to be stored.

Temperature Logger Sensor
M52-SA Plus Temperature Logger Beacon

There are some sensor logger beacons that store sensor values but this tends to be restricted to temperature logging.

What is iBeacon Measured Power?

Most beacons’ configuration app have a setting for iBeacon ‘measured power’ or ‘RSSI at 1m’. This doesn’t change the power output by the beacon. Instead, it’s a value that’s put into the advertising data that declares to receiving devices what the power should be at a distance of 1 meter from the beacon. Receiving devices such as smartphones and gateways can use this to help calibrate a calculation to determine the rough distance from the beacon.

iBeacon Measured power setting

You don’t usually change this value and it’s actually rarely used. In most cases the value is irrelevant and can be ignored. However, if your app or receiving device does use this value, it’s best to first do some tests to see what the power level is in your particular situation. Things like the physical environment, blocking and beacon orientation can affect the actual power level at 1m. Set the value according to your particular scenario.

Read more about transmitted power (as opposed to measured power)

Extending BeaconRTLS™ Reporting

BeaconRTLS™ has a myriad of uses across logistics, manufacturing, healthcare and facilities management. It tracks assets and people to locate them in real time and detect anomalies to improve operational efficiency. This also extends to IoT sensing using sensor beacons that measure temperature, humidity, movement, light, proximity and open/closed.

The system allows you to search for and map the location of beacons. You can set up screen and email alerts based on asset type, location and sensor data. But what if you need more than this?

BeaconRTLS™ stores historical information which provides for industry or scenario specific reporting. For example, recent customers have been asking for Covid specific reports such as room occupancy and who has been in the same room at the same time.

The BeaconRTLS™ API allows your systems or reporting systems to access the data. However, this is of less use for those who want to implement solutions quickly and easily. The tricky part is that we have found every customer tends to need different reporting. Up until now we have been creating ad-hoc reports on a case by case basis.

We have been looking to standardise how custom reports are created with BeaconRTLS™ to reduce effort, time and cost and allow more customers to create reports for themselves. To enable this we have integrated BeaconRTLS™ with Grafana.

Grafana is a free, commonly used open source platform that allows you to show data in custom ways using dashboards and panels. We are creating example Grafana reports for use with BeaconRTLS™ that our customers can use directly or modify for their own use.

Grafana reporting where a beacon has been

Contact us if you are interested in using BeaconRTLS™ and would like to take part in the pilot of BeaconRTLS™ with Grafana.

Understanding Bluetooth LE Reliability

We have previously written about Bluetooth LE on the Factory Floor and Why Bluetooth LE Scanning Doesn’t Always See Devices (the First Time).

There’s a new informative paper by Martin Woolley of the Bluetooth SIG on How Bluetooth® Technology Makes Wireless Communication Reliable. It describes in detail how radio collisions, multi-path propagation, time-dispersion, transmitter-receiver synchronisation, signal strength, receiver sensitivity and buffer overflow can collude to make radio communications unreliable.

The paper explains how Bluetooth modulation schemes, CRC checks, multiple channels, coded PHY, adaptive frequency hopping, flow control and the ATT protocol work to make Bluetooth LE reliable.

The paper also takes a look how Bluetooth Mesh has been designed to achieve reliable communication.

Solar iBeacons

We previously supplied solar beacons. These are beacons with a rechargeable battery topped up via a solar cell.

Solar iBeacon
Solar Beacon

Solar beacon’s weren’t popular and all the models we supplied are no longer manufactured. Some specialist solar beacon companies, whose models we didn’t supply, have also stopped selling beacons. So what happened?

Solar beacons seemed attractive in that they offered the prospect of not needing to change batteries. They weren’t that much more expensive so price wasn’t the reason for poor takeup. Instead, we believe these were the reasons:

  • Solar beacons were always the dumbest of beacons. The features in advanced beacons, such as sensors and advanced settings, never made their way to solar beacons. If you needed these features then the solar beacon wasn’t suitable.
  • While you didn’t need to change the battery because it was flat, the rechargeable battery still had an inherent lifetime of about 10 years. Given that some beacons’ batteries can last up to 5 years, the solar advantage wasn’t that great. Replacement batteries also cost considerably more than non-rechargeable.
  • Solar beacons with glass solar cells were much more fragile causing them to be more likely to be damaged in transit and use. The solar cell also needed to be kept clean which was a problem in some situations.
  • The rechargeable batteries in beacons tended to be LIR2032. Lithium rechargeable batteries suffer from non-use and once flat cannot be used. Beacons in storage required their batteries to be replaced.

In summary, solar beacons have too many problems that, on balance, outweighed what was a less than expected increase in battery life. For next generation self-powered beacons look to Wiliot who power beacons via energy harvesting. Instead of batteries, they use supercapacitors but even these have limited life.

Why Real Time Locating is Becoming More Popular

The recent Nordic Semiconductor wireless quarter magazine contained an article on positioning and real time locating systems (RTLS). RTLS is experiencing growth:

RTLS detects the position of people and assets in real time. Tags are attached to people or assets and the radio signals from the tag allow the location to be determined. The real time aspect is important because it provides the current position automatically, unlike barcode scans and and NRF tags that are only as up to date as the last successful scan. With older, manual, systems, people are lazy and forget to scan.

A complete RTLS system comprises of readers, tag/sensors, application software and communications/network infrastructure.

Asset tracking is being used in industry verticals such as healthcare, defence, education and manufacturing. It commonly tracks tools, equipment, pallets, sub-assemblies, jobs and completed goods.

From Allied Market Research

People tracking has tended to be used more in education and health where the security of individuals is more important than privacy concerns related to tracking people.

RTLS growth is being driven by the benefit of real time tracking allowing processes to be much more efficient. Effort and time is saved when things and people can be found quickly. Alerts notify abnormal conditions to provide for proactive actions. Reports track long term trends to allow identification of patterns that can be used to change processes to improve efficiency.

Bluetooth is popular for use with RTLS because tags and readers are inexpensive compared to other technologies. Bluetooth also works indoors where GPS fails. Unlike other technologies, Bluetooth LE tags have a long battery life of up to several years. There are also tags that perform sensing and Bluetooth LE is suitable for use in electrically noisy environments. Bluetooth also integrates with Bluetooth LE devices such as smartphones, tablets, laptops and desktops.

At Beaconzone we are seeing two new trends in use of RTLS. The first is using RTLS for multiple purposes. Customers often come to us wanting to solve a particular problem but later find the RTLS has a multitude of uses and benefits. This is where a closed solution offering, for example, a lone worker solution, won’t be so flexible.

Established real-time location system market players are shifting from closed solution offerings to including best-in-breed components in application layer

Allied Market Research

The second trend, brought on by Covid, is the tracking of office workers. What might have used to be seen as an invasion of privacy is now being seen as an essential way to monitor room occupancy and determine who has been in the same room as someone else when a person tests positive for Covid.

Read about BeaconRTLS

Read about BluetoothLocationEngine™

Q3 Nordic Semiconductor Wireless Q Magazine

Nordic Semiconductor, the manufacturer of the System on a Chip (SoC) in many beacons, has published the latest issue of Wireless Quarter Magazine. It showcases the many uses of Nordic SoCs.

It showcases a gym management platform using beacons that analyses equipment and zone use. It also mentions the nRF52 SoC, used in beacons, being used in

  • MEZOO’s ECG monitor that detects heart arrhythmia
  • Xiaomi’s Bluetooth LE smart door lock
  • M Lura Health’s 1000 tooth sensor
  • Escort’s fuel level sensor

Juniper Research reports on how the pandemic is accelerating use of IoT:

IoT connections driven by early industrial deployments and pandemic-driven telemedicine applications are projected to reach 83 billion by 2024, a 130 percent growth rate

There are also articles on using tech to prevent deforestation, wellness tech, smart street lighting and precision positioning.