Bluetooth Low Energy

Overview of Bluetooth Low Energy

Bluetooth Low Energy or more popular as BLE or Bluetooth LE was introduced in the Bluetooth 4.0 specification and was a low power consumption protocol, especially for IoT-based implementations. Typically one hears about BLE beacons which are BLE devices that send out Bluetooth signals to electronic devices in the vicinity.


Bluetooth and BLE(Bluetooth Low Energy) are wireless technologies standards. Classic Bluetooth regularly works with large chunks of data but consumes a large amount of battery while BLE handles a lesser amount of data but consumes less energy, therefore, can work with even coin cells which have long battery life.

Typically Bluetooth is used in consumer electronic devices where there is a need to exchange data in a continuous stream. BLE which is marketed as Bluetooth smart is used where there is less amount of data transfer needed between devices and this data transfer happens in an intermittent manner.


BLE operates in the 2.4 GHz ISM band and the standard is maintained by the Bluetooth SIG but it is not compatible with the classic Bluetooth which uses the Basic Rate/Enhanced Basic Rate (BR/EDR) protocol. BLE remains in dormant mode until the connection is initiated. The duration of time of connection is of few ms in BLE.

A Bluetooth beacon is a small device with power being sourced from a coin cell or USB that transmits or broadcasts information. This information is picked by the receiver which may be a phone or a gateway. The BLE can transmit data on 37 data channels, while 3 channels are used for advertisements.

Bluetooth devices operate in the following modes:

  • Advertiser: In this mode, devices transmit advertisement packets on the advertisement channels
  • Scanners: In this mode, devices keep scanning for advertisements on the advertisement channels and don’t form any connections to receive them.
  • Initiators/Central: These devices connect to devices and then receive the advertisement packets. Once the devices form the connection they act as Central devices
  • Peripherals: These devices are the ones that transmit the advertisement in a connection setup with a Central device.

The BLE devices work in 5 states viz Standby, Advertising, Scanning(Active, Passive), Initiating, Connection(Master, Slave). In Standby mode it is waiting for a connection, Advertising mode the device is in a constant broadcast mode. In Scanning mode, the device is constantly looking for advertisements in the advertisement channels. Initiating mode is when the device initiates a connection with another device. Once the connection is set up then the devices connected operate in Master and Slave depending on which device initiated the connection.


Some of the typical use cases of BLE in IoT are listed below:

1] Proximity Marketing

The BLE devices installed in various locations within the shop can detect the presence of a customer in the shop and provide deals based on the contextual information available.


2] Asset Tracking

In this kind of use case, the BLE tags are attached to the Assets to be tracked. The BLE tags instead of broadcasting IDs listen and scan for specific ids which once detected are now tracked in terms of their position. Additionally, these tags can be equipped with sensors for measuring pressure, temperature, motion, light, etc thus enabling them to track these parameters too for these Assets.


3] Indoor Navigation

GPS navigation fails when it comes to indoor navigation. The BLE technology comes to help in this context. There are various techniques like triaging using which the position of the tag or the mobile device’s position can be calculated. Indoor Navigation now becomes possible by providing turn-by-turn directions. This is useful in large buildings, museums, shopping malls, and events where it is difficult to navigate around.


The BLE implementations have had impacts on various verticals some of which are considered below exploring some of the current and future:

1] Retail

The impact of Phygitalization is going to be huge in the future. It has already started percolating but is still waiting for the traction to bring about visible everyday changes. The one area that is definitely seeing the light of the day is that context-based marketing and target marketing. In this, the customers can now get more focused ads like the deals in a shop when they pass by, deals related to their interests or previous purchases. Even there are some implementations where the customers can pick up items and directly walk over to pay the bill without the need for physical verification and billing. You can read more about one such solution which helps in building a new phygital retail commerce.


2] Manufacturing

Another major vertical touted to be impacted by IoT is manufacturing, to the extent of having a term coined IIoT (Industrial IoT) for the possible use cases for the industry.  The influence that IoT has on the industry, starts from monitoring and planning of the core manufacturing process using solutions like Dynamic Production Planning ranging to solutions like pallet tracking solution which help keep track of the various pallets carrying finished goods from various parts of the plant to the customers. Additionally, there are many use cases that lead to operational efficiency and savings as well as proactive maintenance of the machinery.


3] Man Power Services

The problems faced by most manpower service providers are common. Tracking the manpower provided has become a need these days and with technologies like BLE coming to the aid, one no longer needs the person to do something like punching for marking their presence. Additionally, it provides a dynamic attendance leading to no manual intervention or activity that needs to be performed to register the presence. Some solution like the Security Guard Management solution is a good example of such an implementation.   


The BLE devices are now becoming more powerful than before with newer standards and improvements. The newer release Bluetooth 5 brings in advantages to BLE. It makes advances like twice the speed, four times range, and 8 times more advertisement capacity. The coexistence with other wireless devices has also improved.