Bluetooth Low Energy

Bluetooth Low Energy, BLE, is a wireless technology that uses low power for linking devices. BLE’s functioning range is in the 2.4 GHz Industrial, Scientific, and Medical(ISM) band. It plays a vital role in applications that consume less power, runs on batteries for longer duration like months or even years.

Bluetooth Low Energy was announced in the 4.0 version of the Bluetooth spec in 2010. Bluetooth 4.0 is known as Bluetooth Smart or Smart Ready. It is widely in use for fitness trackers, medical devices, and smart home device controls. The original Bluetooth is referred to as Bluetooth Classic. BLE is a new technology that focuses on the Internet of Things (IoT) applications. It is where minimal quantities of data are transmitted at lesser speeds. In the aspects of the technical stipulation, implementation, and the varieties of applications, Bluetooth classic and BLE have their differences.

Some of the essential dissimilarities include:

Bluetooth Classic BLE
They are used for streaming applications like audio and file transfers. They are used for sensor data, device control, and low-bandwidth applications.
not augmented for low power, has a higher data rate Suitable for low power, fewer duty data cycles
Operates in more than 79 RF channels Operates in more than 40 RF (Radio Frequency) channels
Detection on 32 channels, leading to slower connections. Connections are much faster as the detection happens on three channels

BLE’s recent big update was the Bluetooth 5 in December 2016. It had many significant upgrades to the Bluetooth specification, in terms of BLE. The enhancements take in higher speed, improved range, and the advertising data capacity.

Merits and Demerits

Every technology comes with its benefits and boundaries. It determines whether BLE is suitable for the application you’re looking for or not.

Benefits of BLE

  • BLE has optimized and less power usage. It turns the radio off and sends small quantities of data at low speeds.
  • Access to official specification documents is cost-free.
  • Modules and chipsets cost less when matched to other technologies alike.
  • Present in the best smartphones available in the market.
  • Works for both Bluetooth low energy android and Bluetooth low energy iOS devices
  • iBeacon apps have the capability for finding the proximity to the iBeacon-enabled device with Location APIs.

Limitations of BLE

Data throughput: The physical radio layer limits data throughput. The speed of the data rate is influenced by the Bluetooth version applied. The data rate can be 1 Mbps for earlier BLE versions, or 2 Mbps when deploying the high-speed feature.

Range: It is designed for short-range applications, and the operating range is limited. Few factors that influence range limit are as follows:

  • BLE functions in the spectrum range of 2.4 GHz ISM. It is vastly affected by obstacles in the surroundings like metal objects, thick walls, and human bodies
  • Antenna’s design and Performance of the device.
  • The external enclosure of the device.
  • Device positioning.

Internet Connectivity Requirement: For the transmission data from a BLE-only device to the Internet, another BLE device with an IP connection is necessary. Only then this data get received and transmits to a new IP device.

Bluetooth Low Energy Architecture

  • The Physical layer – is the physical radio that operates in the ISM band. It is utilized for interacting and data modulation and demodulation.
  • The Link Layer – interfaces with the Physical Layer (Radio) to deliver the highest abstraction level and a pathway for radio communication.
  • Direct Test Mode – tests the radio operation at the physical level
  • The Host Controller Interface layer – is a standard protocol for permitting the Host layer to interact with the Controller layer.
  • The Logical Link Control and Adaptation Protocol (L2CAP) layer – takes multiple protocols from the upper layers and aligns them in typical BLE packets before they are sent to the lower layers.

The Generic Access Profile (GAP)

GAP is short for Generic Access Profile and offers a framework for BLE devices to communicate with each other. This framework includes:

  • Roles of BLE devices
  • Advertisements (Distribution, Detection, parameters, data)
  • Connection formation (opening connections, accepting connections, parameters)
  • and Security features

The various roles of the BLE device are:

  • Broadcaster: sends out Advertisements and does not accept packets or permit other Connections
  • Observer: pays attention to others transferring Advertising Packets, however, does not initiate any Connection
  • Central: notices and listens to other Advertising devices and can link to an Advertising device.
  • Peripheral: Advertises and receives Links from Central devices.

The Generic Attribute Profile (GATT)

Connecting two BLE devices enables data transfer between them possible. The Generic Attribute Profile (GATT) outlines the format for data exposure by a BLE device and the procedures for data access.

GATT has two leading roles:

  • Server – the device that reveals the data and possibly a few aspects of its behavior that a new device might control.
  • Client – the device that interfaces with the Server. It helps to read the Server’s visible data and regulates the Server behavior.

Both the Bluetooth low energy android and Bluetooth low energy iOS device is capable of acting as the Server and Client simultaneously.

Services and Characteristics

Services and Characteristics are the two most important and widely used terms in BLE. Thus it is essential to understand them for BLE devices that launch a linking with one another.

  • Attributes are a general term for any data shown by the Server and express the data’s structure.
  • Services are a combination of one or more related Attributes and Characteristics that fulfill specific server functionality.
  • Characteristics are a part of Service and it signifies an amount of information or data that a Server needs to picture it to a client.
  • Profiles define the behavior of the Client and Server about Services, Characteristics, Connections, and security requirements.

BLE has six primary Characteristics operations:

  1. Commands: They are sent by the Client to the Server and do not need a Response
  2. Requests: They are sent by the Client to the Server and need a Response.
  3. Responses: The Server sends them to a particular Request.
  4. Notifications: They are sent by the Server to the Client to inform that a particular Characteristic Value has changed.
  5. Indications: The Server sends them to the Client reporting on status.
  6. Confirmations: are the acknowledgment packets sent by the Client to the Server.

BLE technology holds a lot more to contribute in the future. We provide exceptional Bluetooth Low Energy technology solutions for our clients worldwide. Send us your requirements to contact@blemobileapps.com

Also Read:

Using Bluetooth Low Energy (BLE) for Competitive Advantage

Bluetooth Low Energy (BLE): Make Your Product, a Smart Product