Bluetooth is a short range wireless technology, which was first introduced by Ericsson Company in 1994 after its initiation in 1989. This technology operates in the ISM band, which is reserved for industrial, science and medical applications. This is a free band and does not require lengthy licensing procedures and fees. It operates in two frequency ranges – 2400 to 2483.5 MHz and 2402 to 2480 MHz – via the frequency hopping spread spectrum radio interface technology. Bluetooth transmission frequency band is divided into 79 Bluetooth channels to transmit the data packet. The latest version of this communication technology known as Bluetooth Low Energy or BLE accommodates 40 channels because it uses 2 MHz spacing guard band.
Bluetooth Low Energy or BLE is developed by Bluetooth Special Interest Group BSIG for high energy efficiency and performance. This technology is commonly marketed as Bluetooth Smart technology in the marketplace. The devices enabled with the BLE technology can operate for many months even years on a single button cell/battery. BLE technology is very suitable for the internet of things (IoT). BLE technology can operates with a maximum speed of 50 Mbits/s up to an effective distance of 800ft (240 meters).
Bluetooth Technology Versions
Bluetooth technology has evolved through multiple versions since its inception. There are five major versions with its sub-versions released so far, as given below.
Bluetooth 1 (with multiple sub releases)Bluetooth 2 (with multiple sub releases)Bluetooth 3Bluetooth 4 (With multiple sub releases)Bluetooth 5
Bluetooth in Access Control Applications
Like other short range wireless access control technologies, such as Zigbee and others; Bluetooth can also be efficiently used as an effective access control technology. The main applications of Bluetooth access control include home automation and access security systems.
There are large numbers of software applications available in the market that can be configured – commonly known as profiling – on the Bluetooth enabled mobile phones to establish short range communication with the Bluetooth enabled proximity sensing devices. Other than those software applications, this technology can be implemented in an autonomous Bluetooth access control system too.
In a normal access control system based on iPhone, you will need a proximity reader enabled with the Bluetooth signals. A software application is installed on the iPhone smart phone, and the application is then profiled for the access security use. When the smart phone is neared to the proximity reader, the application communicates with the reader and thus, exchanges the security key to authenticate and open the door lock.
Similarly, in an automated and networked house or office, your phone communicates with the centralized access controller, which controls the door locks in a networked environment. The security key is authenticated and the authorized door is opened through the signals from the main access controller.
The introduction of iBeacon protocol is another important milestone in using Bluetooth technology in more access control and security related applications. It can be extensively used in the applications pertaining to location finding, which subsequently will trigger a major potential of marketing services. Recently, iBeacon has been implemented in multiple BLE enabled devices that can easily communicate with the mobile applications in their respective ranges over Bluetooth technology. The power consumption of iBeacon transmitter is very low and can operate for many months continuously on a small battery.
Access control over Bluetooth technology uses the mobile devices in association with the third party controllers and readers; this will reduce the hardware cost for this particular application. Only software profiling is sufficient to use your mobiles devices in different access control systems. With the advent of BLE technology in the market, this field has a bright future in this industry.