What are Bluetooth Tunnel Beacons?

This is a feature in Google Maps on Android that improves navigation through tunnels, addressing the long-standing challenge of maintaining accurate location tracking when GPS signals falter.

Historically, tunnels have posed a significant challenge for digital navigation tools, primarily due to the inability of GPS signals to penetrate the thick layers of earth and concrete. This often results in a loss of real-time location tracking. However, Google Maps has improved the situation through the introduction of Bluetooth tunnel beacons, a feature that uses the power of Bluetooth technology to offer an unprecedented level of location accuracy in subterranean environments.

Bluetooth tunnel beacons operate by emitting signals that are received by a user’s smartphone, providing precise location data to the device. This feature, using technology already implemented by Google-owned Waze utilises these signals in conjunction with the device’s mobile connectivity. Together, they deliver navigation assistance, mirroring the capabilities of a traditional GPS connection.

The feature appears under Settings > Navigation Settings and under the ‘Driving Options’ section near the bottom. The feature is disabled by default, and is described as: ‘Scan for Bluetooth tunnel beacons to improve location accuracy in tunnels’.

The effectiveness of Bluetooth tunnel beacons, however, depends on the presence of these beacons within tunnels. Waze has already installed these beacons in several major cities around the world, such as New York City, Chicago, Boston, Paris, Rio de Janeiro and Brussels.

Bluetooth Ad-hoc Collision Avoidance System

Research, Ad-hoc collision avoidance system for Industrial IoT by Dan Garcia-Carrillo, Xabiel G. Paneda, David Melendi, Roberto Garcia, Victor Corcoba, and David Martínez, presents a novel system for enhancing safety in industrial environments where heavy machinery operates near workers. The system, designed to prevent collisions, uses Bluetooth beacons to detect the presence of workers and alerts machinery drivers through visual and haptic signals.

In their methodology, the authors employed Bluetooth devices to detect workers nearby and used Raspberry Pi to manage the Advanced Driver Assistance Systems (ADAS). This system evaluates surrounding Bluetooth emitters and triggers feedback mechanisms such as LED strips and vibrating seatbelts. The study acknowledges the accuracy limitations of Bluetooth for precise location but emphasises its effectiveness in proximity detection. A real excavator and workers carrying Bluetooth emitters were used to implement and test this proof of concept.

The results showed that the system could successfully detect the presence of workers relative to heavy machinery. Drivers received simple yet effective feedback through visual and haptic alerts, based on the proximity of workers. Notably, the system was found to be affordable and less intrusive than camera-based solutions, with Bluetooth proving sufficient for this application.

The authors concluded that their proposed system significantly enhances safety in industrial settings with heavy machinery. It effectively alerts drivers of nearby workers, thereby reducing the risk of accidents.

Process Control in Manufacturing and Logistics with Bluetooth Beacons

In sectors such as aerospace, automotive, logistics, transit management and process-driven manufacturing, the quest for efficiency and precision is unending. The integration of Bluetooth beacons into monitoring process control provides a significant leap in addressing these challenges. Traditionally, manual processes suffer from a range of issues. Bluetooth beacons offer a compelling solution to these age-old problems.

Firstly, there’s the matter of process visibility and optimisation. In complex environments like aerospace or automotive manufacturing, keeping track of components and processes is critical. Bluetooth beacons enable real-time tracking and provide data-driven insights, allowing for better decision-making and process optimisation. This technology ensures that every aspect of the manufacturing process is visible and under control, leading to enhanced efficiency and productivity.

A common issue in logistics and transit management is the misplacement of items; things can’t be located or are found in the wrong place. Bluetooth beacons counteract this by offering precise location tracking. This ensures that items are always where they need to be, thereby reducing the time and resources spent on locating misplaced items. In transit management, this translates to smoother operations and reduced delays.

Interaction, or the lack thereof, between components or processes, is another challenge that Bluetooth beacons can handle. In scenarios where two or more things are (or are not) interacting as they should, beacons provide real-time interaction data. This information is crucial in environments where the interplay between different components or processes is key to successful operations.

When it comes to counting, the issue often lies in having too many or too few items in a certain place. Bluetooth beacons facilitate accurate inventory management, ensuring that the right quantity of materials or products is always available where needed. This precision is particularly vital in just-in-time manufacturing processes, where inventory accuracy is paramount.

Time management is another critical factor in process control. A task taking too long or not long enough can significantly impact overall productivity. Beacons can track the time spent on specific tasks, providing insights into potential bottlenecks or inefficiencies. This data is invaluable for optimising workflow and ensuring that time is utilized effectively.

Lastly, sequence plays a pivotal role in manufacturing and logistics. When things happen in the wrong order, it can lead to a cascade of issues. Bluetooth beacons, with their ability to track and record sequences of events, ensure that processes follow the correct order, thereby avoiding costly mistakes and delays.

Anchor-based Bluetooth Low Energy (BLE) 5.0 Positioning

A recent new paper, BLE-Based Indoor Localization: Analysis of Some Solutions for Performance Improvement, focuses on improving the performance of indoor localisation using an anchor-based system based on Bluetooth Low Energy (BLE) 5.0 technology, specifically employing the Received Signal Strength Indicator (RSSI) for distance estimation. Different solutions to enhance this localisation technology’s performance are explored, with an emphasis on combining various approaches to identify the most effective one. These solutions include different RSSI signal conditioning, anchor–tag distance estimation techniques and methods for estimating the unknown tag position.

An experimental analysis was conducted in a complex indoor environment, marked by the continuous movement of working staff and numerous obstacles. The results showed that the exploitation of multichannel transmission, using RSSI signal aggregation techniques, significantly improved the localisation system’s performance, reducing the positioning error from 1.5 meters to about 1 meter.

Other solutions, such as RSSI signal filtering, distance estimation with an empirical propagation model or Machine Learning (ML), numerical optimisation and ML models for estimating the tag’s unknown position, also impacted performance but to a lesser extent. These solutions resulted in either a decrease or an increase in positioning errors, depending on the specific combination of solutions adopted.

The study’s findings suggest that the use of multichannel transmission and the combination of RSSI signals from different transmission channels are crucial for achieving optimal performance. This approach leverages the full potential of BLE 5.0 technology and is the most significant factor in reducing positioning errors. The paper concludes that the results can guide designers in choosing appropriate solutions based on the desired accuracy of the localisation system. However, it’s noted that the results are specific to the tested conditions and may vary under different operating scenarios.

Bluetooth 4 is Still Dominant

For technology, newer versions typically overshadow their predecessors, but the Bluetooth beacon market has been different. Despite the introduction of Bluetooth 5, the significant majority of beacon applications continue to rely on Bluetooth 4. This is not a mere reluctance to adopt newer technology but a practical decision rooted in compatibility concerns, especially with existing smartphones.

Bluetooth 5 arrived with much fanfare, offering significant improvements over Bluetooth 4. It promised doubled speed, quadrupled range and an eightfold increase in data broadcasting capacity. These advancements opened new possibilities for IoT applications, making it an attractive prospect for beacon technology. However, this leap forward did not translate into immediate widespread adoption in the beacon ecosystem.

The core issue hindering the widespread adoption of Bluetooth 5 beacons lies in device compatibility. The majority of smartphones in circulation still operate on older Bluetooth versions. While Bluetooth 5 is backward compatible, meaning it can work with devices supporting older versions, the reverse is not true. A beacon using Bluetooth 5’s advanced features cannot be fully used by a device that only supports Bluetooth 4.

Bluetooth 4, particularly 4.2, introduced Low Energy (LE) technology, which was a game-changer for battery-powered devices like beacons. It provided an efficient way to transmit small amounts of data over a reasonable range without draining the battery. This efficiency made Bluetooth 4 beacons incredibly popular for a wide range of applications, from retail marketing to indoor navigation and asset tracking.

In real-world scenarios, the extended range and speed of Bluetooth 5 are often unnecessary for typical beacon applications. Most beacon use-cases, like sending notifications or tracking assets, require neither long-range transmission nor high-speed data transfer both of which usually cause more Bluetooth battery use. Bluetooth 4’s capabilities sufficiently meet these requirements, making it a practical choice.

The transition to Bluetooth 5 beacons will likely charge a little as the market penetration of Bluetooth 5-enabled smartphones increases. However, only applications demanding higher data throughput and longer ranges will gravitate towards Bluetooth 5. However, until there is a significant shift in the smartphones, Bluetooth 4 will continue to be the backbone of beacon technology.

In conclusion, while Bluetooth 5 offers technological enhancements, the beacon market’s reliance on Bluetooth 4 is underpinned by practical considerations. Compatibility with the existing smartphone ecosystem and the adequacy of Bluetooth 4 for current applications justify its continued dominance.

Indoor Locating Using Beacons in Nursing Care

The new paper Relabeling for Indoor Localization Using Stationary Beacons in Nursing Care Facilities by Christina Garcia and Sozo Inoue from the Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, Japan, presents a study on enhancing machine learning for indoor localisation in caregiving, specifically in nursing homes, using Bluetooth Low Energy (BLE) technology.

The study addresses the challenge of limited data available for training machine learning models in indoor localisation, which is critical for monitoring staff-to-patient assistance and managing workload in caregiving environments. The authors propose a data augmentation method that repurposes the Received Signal Strength (RSSI) from various beacons by re-labeling them to locations with fewer data samples, thus resolving data imbalances. This method uses standard deviation and Kullback–Leibler divergence to measure signal patterns and find matching beacons for re-labeling. Two variations of re-labeling are implemented: full and partial matching.

The performance of this method is evaluated using a real-world dataset collected over five days in a nursing care facility equipped with 25 Bluetooth beacons.

Overall, the study highlights the effectiveness of the proposed re-labelling method in enhancing indoor localisation accuracy in nursing care facilities, providing a valuable contribution to the field of caregiving and workload management.

Sensor Beacon List Updated

We offer a range of sensor beacons but what each beacon actually senses or detects is buried deep in the respective beacon descriptions.

As we have recently added new sensor beacons, we have updated our downloadable pdf showing what each beacon can detect.

If you want to know how you might use these beacons, take a look at our articles on Beacon Proximity and Sensing for the Internet of Things (IoT), Using Bluetooth LE and Using Bluetooth LE Sensors.

Why is There a Bluetooth Beacon in My Hotel Room?

The presence of a Bluetooth beacon in your hotel room is likely part of the hotel’s efforts to enhance guest experience and operational efficiency. These beacons are used for various purposes.

These beacons can help in providing location-based services. For example, if the hotel has a mobile app, it might send you notifications about special offers or events based on your location within the hotel.

In larger hotels, these beacons can assist guests in navigating to facilities like the gym, restaurant, or conference rooms. They can help the hotel staff in monitoring and managing room status, like whether the room is occupied or needs cleaning, thus improving efficiency.

In the context of health and safety, especially post-COVID-19, such technology can facilitate contactless check-ins and check-outs, or even contactless room service. Hotels may use these beacons to collect data on guest movements and preferences to improve their services and tailor their offerings.

A Summary of Bluetooth Attacks

A recent study with the strange title SoK: The Long Journey of Exploiting and Defending the Legacy of King Harald Bluetooth (pdf) provides a comprehensive analysis of the security and privacy issues surrounding Bluetooth technology. Authored by Jianliang Wu, Ruoyu Wu, Dongyan Xu, Dave (Jing) Tian, and Antonio Bianchi from Purdue University and Simon Fraser University, it explores the evolution of Bluetooth security over 24 years, focusing on both attacks and defences.

The paper begins by summarising the evolution of Bluetooth security features since its first version, discussing the introduction of Bluetooth Low Energy (BLE) and Mesh protocols. It then looks into a systematisation of 76 attacks and 33 defences, categorising them based on their affected layers in the Bluetooth stack, the protocols they target, and their threat models.

Key observations include the increasing number of privacy attacks during the BLE device discovery phase, challenges in pairing security due to user mistakes and a mismatch between the assumptions of Bluetooth specifications and their real-world implementations on modern operating systems. The authors also highlight that while Bluetooth’s security has improved over time, there remain significant gaps in both security and privacy features that need addressing.

The document further explores attacks and defences in detail, divided into different layers of the Bluetooth stack: the physical layer, firmware layer, and host layer. Each layer faces unique challenges, from signal eavesdropping and injection at the physical layer to firmware exploitation and host exploitation attacks. The authors categorise these attacks based on their goals, affected protocol, phase, and attack model, providing a comprehensive overview of the current state of Bluetooth security.

Wireless Quarter Magazine

Nordic Semiconductor, the manufacturer of the System on a Chip (SoC) in most beacons and number one supplier of SoCs for Bluetooth LE solutions, has published the latest online issue of Wireless Quarter Magazine. It showcases the many uses of Nordic SoCs.


The latest issue of the magazine highlights the use of the Nordic SoCs in the following Bluetooth solutions:

  • AirSuite hazardous indoor conditions monitor
  • NNOXX health and fitness performance wearable
  • Wevolver perishable goods transport solution
  • GreaseBoss machinery lubrication management sensor
  • Coral Sense connected construction module using Bluetooth Mesh

There are also in-depth articles on Cellular IoT, how AI and machine learning are transforming IoT, Cellular IoT and DECT NR+, Smart Power Grids and Connected Construction.