Getting Started With BLE A Complete Guide

Going down the memory lane, Bluetooth and its applications are in use since the 2000s. Since the time of its development and usage, Bluetooth has undergone numerous changes and advancements. One among the most important of them all is the development and introduction of Bluetooth Low Energy.

Bluetooth Low Energy is abbreviated as BLE (Bluetooth LE, and is additionally also marketed as Bluetooth Smart). Bluetooth Low Energy (BLE), sometimes known as Bluetooth Smart, maybe a lightweight subset of original Bluetooth that debuted with the Bluetooth 4.0 core specification. 

In this article, we are going to talk about Bluetooth Low Energy Technology which will help you in getting started with BLE.

What Is Bluetooth?

Before diving into the small print of Bluetooth Low Energy, it is essential for us to understand the meaning and dealing of Bluetooth. The Bluetooth specifications specify the technical components that developers utilize to build the interoperable devices that structure the thriving Bluetooth ecosystem.

The Bluetooth Special Interest Group (SIG) oversees Bluetooth specifications, which are updated and improved on an everyday basis by Bluetooth SIG Working Groups to satisfy changing technology and market needs.

The majority of people associate Bluetooth with a wireless headset or another gadget that connects you to the information that you are transmitting. Bluetooth is a wireless connection that exists between your phone and the device to which you are linked. This mechanism allows data to be sent over small distances without the utilization of cables.

What Is Bluetooth Low Energy?

Bluetooth gadgets are continually being developed and reinvented. Do you recall when Apple initially released AirPods? There are now various different versions of this Bluetooth connectivity device, including innovations that help with battery life, which leads us to Bluetooth Low Energy. BLE (Bluetooth Low Energy) is a type of wireless communication that is designed for short-range communication. Like Wi-Fi, BLE allows devices that are connected to interact with one another. 

BLE is designed for circumstances where battery life is more important than high data transfer speeds. Assume you would like to broadcast marketing campaigns within the vicinity of a just introduced headset. As the quantity of data and information that you would send to a visitor’s smartphone is so minimal, BLE-enabled beacons can do the task fast and without exhausting the battery. 

What Makes Bluetooth Low Energy (BLE) Different?

Bluetooth Low Energy is a separate Bluetooth standard that is incompatible with conventional Bluetooth. The latter was originally commercially released almost 20 years ago, and the Bluetooth Special Interests Group (SIG) is no longer actively developing it. Not being developed certainly does not imply not being used. It is commonly found in devices that demand a constant connection, mostly audio devices such as wireless speakers and headphones. 

The main distinction between Bluetooth Low Energy and Bluetooth is Bluetooth Low Energy’s ability to consume less energy. When compared to traditional Bluetooth, BLE is designed to use significantly less power and cost while retaining a similar communication range. Applications with minimal energy consumption can run for longer periods of time on a small battery. Although this is inconvenient when talking on the phone, it is critical for applications that transmit little amounts of data on a regular basis.

Bluetooth Classic is meant for continuous two-way communication, but Bluetooth Low Energy (BLE) sends smaller data packets over shorter durations of time. Just as the name implies, Bluetooth Low Energy consumes far less energy that is, up to 100 times less than Bluetooth Classic. Bluetooth Classic, on the other hand, provides a bigger range and higher data throughput because it is not as constrained. Bluetooth Low Energy is natively supported by mobile operating systems such as iOS, Android, Windows Phone, and BlackBerry, as well as macOS, Linux, Windows 8, and Windows 10.

The Specification

With version 4.0 of the Bluetooth Core Specification, the Bluetooth SIG launched Bluetooth Low Energy in June 2010. The specification had been in the works for some years, and the majority of the contentious portions and decisions had been smoothed out by the companies engaged in the development process, with a few minor problems remaining to be addressed in future revisions.

Bluetooth 4.1, the first significant update, was launched in December 2013 and is the current standard for anyone developing BLE products. Although the essential building blocks, procedures, and concepts remained unchanged, this release included a number of updates and enhancements to improve the user’s experience.

4.1 is backward compatible with 4.0, as are other Bluetooth specifications, ensuring proper interoperability between devices that implement multiple specification versions. The specifications allow developers to release and qualify products for either version, though thanks to the rapid adoptions of the latest specification releases and therefore the incontrovertible fact that the 4.1 version standardized several common practices among devices, it is recommended that developers target the foremost recent version available.

Unless otherwise stated, the Bluetooth 4.1 specification is employed as a reference during this work. We shall specify when the preceding 4.0 standard does not cover a given region wherever relevant, especially when describing a notable modification or addition.

Bluetooth Low Energy (BLE) technology appears to be taking the world one step closer to universal internet connectivity. Classic Bluetooth, which is used in mobile phone in-car hands-free devices, is notorious for consuming a lot of power. Bluetooth LE, which is part of the Bluetooth Special Interest Group’s (SIG) current Bluetooth 4.1 protocol, is significantly less power-hungry. It is claimed that ordinary slave nodes running Bluetooth LE can function for months or even years on a single coin cell.

Part-1 of this guide offers an in-depth and detailed description of the specifications, adaptations and other aspects of BLE. With a set of useful attributes and functions, BLE also comes bearing some limitations that need to be highlighted. The following section of the article talks about the same.

Key Limitations

• First and foremost, Bluetooth LE does not provide Classic Bluetooth-style functionality in a more energy-efficient format. It does not allow designers to suddenly obtain Classic Bluetooth functionality without a significant power drain. If a specific design requires Classic Bluetooth capabilities, such as over-the-air streaming of audio or other data at data rates of 1Mbps or greater, the same high-power budget will be required.
• Bluetooth LE is designed for a very specific range of applications. Lightning-quick connection, the transmission of short bursts of tiny packets of data, and lightning-quick disconnection are all possible with this technology. This ability to send ‘pulsed’ data is ideal for communicating morsels of information like ‘the temperature in the refrigerator has climbed above 5°C’ or ‘the room is not occupied.
• Only three of a Bluetooth LE device’s 40 radio channels are needed to advertise its presence to other Bluetooth devices (rather than 32 in Classic Bluetooth), implying that its advertising transmissions are substantially faster (1.2ms rather than 22.5ms) than Classic Bluetooth. With 37 data transmission channels available, it can readily avoid interference and hence keep transmission times short.Of course, the operation of Bluetooth LE is not by chance: the radio’s capacity to spend lengthy periods in deep sleep mode is due to a combination of pulsed transmission capability and the freedom to hop across frequency channels, allowing for quick interference-free communications.
• It also means that Bluetooth LE will only be utilized to send ‘state’ data rather than streaming content. Although Bluetooth LE devices may specify a theoretical maximum data rate in bits per second, if an application’s designer is forced to think in terms of ‘data rate,’ Bluetooth LE is the incorrect technology for the job. A decent Bluetooth LE application is one in which the Bluetooth radio is turned off practically all of the time.

Network Topology

Bluetooth Low Energy devices can communicate with different devices by the use of two different network topologies, namely: Broadcasting and Connections.

• Broadcasting 

You can send data to any scanning device or receiver within listening range using connectionless broadcasting. This technology essentially allows you to send data one-way to anyone or anything that can pick up the communicated data. Broadcasting is crucial to comprehend since it is the only means for a device to send data to several peers at the same time.

You can broadcast data by using BLE’s advertising features. Broadcasting is quick and simple to use, and it is an excellent option if you simply need to send a little quantity of data to several devices on a regular basis. When opposed to a conventional connection, one of the key disadvantages of broadcasting is that there are no security or privacy safeguards, that is, any spectator device can receive the data being broadcasted, hence the broadcasting topology may not be suitable for sensitive data.

• Connections 

Connections are one of the most widely used network topologies which is not just convenient and better but also establishes a secure bidirectional one-to-one (1:1) data transfer link. A peripheral/ central GAP roles pair is required to make a BLE connection. The peripheral GAP function is designed to use as little computing power and memory as possible.

Most of the time, this is the job chosen for the device under development. A central device receives connectable advertising packets from a peripheral and makes a request to the peripheral to establish an exclusive connection between the two devices to commence a connection. The peripheral stops advertising once the connection is established, and the two devices can begin exchanging data in both directions.

A connection is thus nothing more than the periodic exchange of data between the two peers involved in it at certain times in time (connection events). It is worth noting that, while the center is the device that handles connection setup, data can be transmitted independently by either device during each connection event, and the roles have no bearing on data throughput or priority.