We live in the future, and access control is no exception. While keys and keycards are still in use, Bluetooth-enabled smartphones paired with proximity readers are fast becoming standard in physical access control thanks to their ease of use, versatility, and the sheer utility of Bluetooth Low Energy Standard technology.
Want to know the ins and outs of how to make Bluetooth work for access control? Let’s get into just how a Bluetooth reader works:
Bluetooth Reader: What is it & How does it work
Bluetooth is a short range wireless technology that operates using radio waves transmitted on the ISM band. ISM stands for “industrial, science, and medical,” and unlike other radio bands it costs nothing and requires no licenses to use–which is part of what makes Bluetooth so cheap and easily adoptable.
This means that Bluetooth operates on a frequency band that doesn’t interfere with most other household or commercial devices, like TVs or radios. And unlike TV or radios, Bluetooth signals are specifically developed to send and receive at a fairly close range, instead of over long distances.
The newest iteration of the Bluetooth transmission standard is known as Bluetooth Low Energy Standard, or BLE, which refines ISM use further by limiting Bluetooth devices to 40 channels within ISM with a 2 MHz spacing guard band. BLE signals consume less power from devices, while also being more accurate, less susceptible to interference, and well able to carry large data packets with ease.
All of this makes Bluetooth an incredibly useful tool when it comes to access control. How? Let’s dive in a bit deeper:
Bluetooth Reader Access Control
The most common current applications for Bluetooth are multimedia data transfer–wireless headphones linked to a phone or laptop, for example, or a wireless keyboard.
And a growing area is in the Internet of Things category of devices which, while often joined to a larger WiFi network, can make use of Bluetooth’s ultra-reliable short-range signals as well to transmit data packets.
But a third area of application for Bluetooth is in physical access control and Bluetooth-enabled door readers. Bluetooth-enabled smartphones can, with the right app, work with Bluetooth-enabled electronic door locks, and it’s a quick, convenient, and tech-savvy option for many commercial applications.
Commercial Bluetooth Door Lock
Access control for doors originated with simple locks and keys, which works well as long as the key is in the right hands and doesn’t get lost. Then in recent decades, this has advanced to electronic proximity cards equipped with simple data chips containing authorization information, paired with card readers that scan and read these chips using Zigbee, ZWave, or NFC short-range technology, and open the door or keep it locked accordingly.
Bluetooth readers build on this by taking advantage of a data device that many people already have and whose whereabouts they are always aware of: the smartphone.
There’s an app for almost everything, and this is no exception. Here’s how it works:
- You’ll need to download an app that ‘profiles’ your phone as a receiver for short-range Bluetooth-enabled proximity sensors. These apps are available for iOS and Android, and which one you end up using will depend on which one best communicates with your door reader.
- After the app is live and loaded with your credentials, you’ll need to give it permission to access your phone’s Bluetooth antenna.
- From this point your phone will be actively alert for a proximity reader emitting Bluetooth signals.That means, when you bring your smartphone close to a reader, your phone will send your credentials and security key to the reader using BLE signals, which the Bluetooth door reader will then receive, approve, and open the same way it would for a key card.
Remote Locking And Unlocking With Bluetooth
Many of the Bluetooth reader access control apps have a dashboard that allows you to visualize different doors you’re authorized to enter. And some of them also allow you to lock or unlock these doors remotely, which can come in handy if you’re letting a visitor in from the inside, or if the Bluetooth beacon on your phone is out of order.
However, there is a limited maximum range for remote locking and unlocking–usually around ten feet away from the proximity reader. Remember that Bluetooth is by design a short-range technology.
So if you need to regularly allow visitors remote access, another good option is a video intercom system, which has more robust remote-control features.
Disadvantages of Bluetooth Reader Smart Locks
Wake Up Delay
Smartphones have a limited battery life, so they do whatever they can to save battery during the day. If a smartphone were constantly broadcasting from its Bluetooth antenna, it would run down its battery much more quickly, requiring more frequent charging and reducing the battery’s overall lifespan.
As a result, smartphones are programmed to let some things in the background “go to sleep” instead of keeping them awake and actively draining power–Bluetooth included.
What this means practically is that there is often a time lag between when a smartphone receives a proximity beacon, wakes up, and exchanges signals. It’s likely to take slightly longer than a key card.
Distortion and Noise
A Bluetooth signal can be warped by three things: microwaves, strong WiFi, and other Bluetooth signals.
Microwaves are simply powerful enough to interfere with the frequencies where Bluetooth waves travel, whereas WiFi signals can overlap with Bluetooth signals, and other Bluetooth signals can end up passing through the same space.
These signals passing through each other can create distortion and interference, or noise, that can keep the Bluetooth from functioning properly.
But for all three of these, the answer lies in proximity. Moving the Bluetooth device away from microwaves or a WiFi router will free up the airwaves. And because Bluetooth is short-range, two Bluetooth devices will only interfere with each other when they are right next to each other.
Advantages of Bluetooth Reader Smart Locks
While Zigbee, ZWave, or NFC short-range technology operate much like Bluetooth does, they are primarily limited to a certain stable of access control devices.
Bluetooth and BLE, meanwhile, is a technology that has been adopted in many different industries and markets. This means there are generally more options for Bluetooth-enabled proximity devices than these other short-range communications.
Bluetooth can be used for more than just door access control. The same system and principles can be followed to make your smartphone a key that unlocks other devices, computer terminals, servers, and equipment–all in one package that’s easy to keep track of, easy to navigate, and can even be geolocated when lost.