Bluetooth Low Energy (BLE)

Bluetooth Low Energy (BLE) is a wireless communication technology that has become increasingly popular with the Internet of Things (IoT)

Article publié le 05/03/2023
Bluetooth Low Energy (BLE)

Introduction

Bluetooth Low Energy (BLE) is a short-range wireless communication technology that has become increasingly popular in the Internet of Things (IoT) in recent years. It allows devices to communicate with each other with very low power consumption, making it an ideal choice for IoT applications that require wireless communications with long battery life.

What is Bluetooth Low Energy (BLE)?

Bluetooth Low Energy is a wireless technology designed to enable short distance communications with very low power consumption. It uses a 2.4 GHz frequency band to transmit data over short distances (up to 100 meters), making it an ideal choice for IoT applications.

Do not confuse Bluetooth Low Energy with standard Bluetooth

Standard Bluetooth and Bluetooth Low Energy (BLE) are two wireless communication technologies that allow devices to connect with each other. However, there are significant differences between the two.

Standard Bluetooth, also known as Bluetooth Classic, is a wireless communication technology that was developed in the 1990s. It is mainly used for devices that require real-time data transmission, such as headphones and the speakers.

In contrast, Bluetooth Low Energy was introduced in 2010 as an extension of standard Bluetooth technology. It is designed to provide low-power connectivity for IoT devices that need to communicate with other wireless devices while maintaining battery life.

So, the main difference between standard Bluetooth and Bluetooth Low Energy is their power consumption. Standard Bluetooth requires more power consumption to transmit data, while Bluetooth Low Energy requires much less power, making it ideal for IoT devices.

The different categories and scopes of BLE

Bluetooth Low Energy is divided into different categories based on their range. Categories are defined by their transmit power, range, and power consumption. There are four categories:

  • Class 1: 100 mW transmission power with a range of up to 100 meters
  • Class 2: 2.5 mW transmission power with a range of up to 10 meters
  • Class 3: 1 mW transmission power with a range of up to 1 meter
  • Class 4: 0.5 mW transmission power with a range of up to 0.5 meters

Advantages of Bluetooth Low Energy

  • Low Power Consumption: Power consumption is very low, allowing long battery life for connected devices.
  • Low cost: Bluetooth Low Energy technology is inexpensive and can be easily integrated into many IoT products.
  • Interoperability: Bluetooth Low Energy technology is standardized and interoperable, which allows different devices to communicate with each other.
  • Connectivity: Bluetooth Low Energy technology allows easy and fast connectivity between different devices.

Disadvantages of Bluetooth Low Energy

  • Limited range: the range of Bluetooth Low Energy is limited to a few meters.
  • Limited Bandwidth: The bandwidth of Bluetooth Low Energy is limited, which can cause data transmission speed problems for certain types of applications.
  • Latency: Latency can be an issue in some applications, as the response time can be longer than for other wireless communication technologies.

BLE and Mesh System

The Mesh system is a feature of Bluetooth Low Energy that allows multiple devices to communicate with each other. Bluetooth devices can be meshed, thus creating a Mesh network where each device can serve as a relay to send a message over the network.

The Mesh network has several advantages and disadvantages:

Benefits :

  • Large range: The Mesh Bluetooth system is able to cover large distances thanks to the mesh connectivity between devices, allowing extended coverage and better distribution of the load on the network.
  • Scalable: The Mesh Bluetooth system can be easily expanded as new devices are added, making it an ideal choice for ever-changing IoT networks.
  • Reliability: With mesh connectivity, the Mesh Bluetooth system is highly resilient and able to automatically reroute data in the event of connection loss or device failure.
  • Low Power Consumption: The Mesh Bluetooth system typically uses low power consumption, making it an ideal option for battery-operated IoT devices.
  • Security: Mesh Bluetooth system provides enhanced security through data encryption, permission management and device authentication

Disadvantages:

  • High cost: Mesh Bluetooth compatible devices can be more expensive than standard Bluetooth devices.
  • Complexity: Setting up and configuring the Mesh Bluetooth system can be more complex than standard Bluetooth systems.
  • Latency: Mesh connectivity can cause increased latency due to the time it takes to transmit data through the network.
  • Power consumption: Although the power consumption of the Mesh Bluetooth system is generally low, it can be higher than that of standard Bluetooth in certain circumstances, due to the need to reroute data through the network.

Examples of using Bluetooth Low Energy

Bluetooth Low Energy is used in many IoT products for various sectors, here are some examples:

  • Connected watches: connected watches often use Bluetooth Low Energy technology to connect to smartphones. This allows users to receive notifications and updates from their smartphone directly to their watch.
  • Fitness sensors: Fitness sensors often use Bluetooth Low Energy technology to connect to smartphones or connected watches. This allows users to track their physical activity in real time and receive health data.
  • Beacons: Beacons are small transmitters that send Bluetooth Low Energy signals to nearby devices. They are used in stores to send notifications to customers, for geolocation applications, or for inventory tracking systems.
  • Medical devices: Many medical devices use Bluetooth Low Energy technology to transmit health data to connected devices. This allows healthcare professionals to monitor the health of their patients remotely.
  • Home automation systems: Home automation systems often use Bluetooth Low Energy technology to connect the various devices in the house, such as lights, thermostats and smart locks.

Conclusion

In summary, Bluetooth Low Energy is a popular wireless technology for IoT devices that require low power consumption and easy connectivity. Although it has limitations in terms of range and bandwidth, Bluetooth Low Energy offers many advantages such as low power consumption, low latency and high interoperability. With the growth of IoT, we can expect to see more and more devices using this technology in the coming years.