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Rahmantutul
Rahmantutul

Posted on • Edited on • Originally published at bestwirelessbluetoothheadphones.com

Bluetooth 5.1: What’s Different, and How It Works, Everything You Need To Know

Whether you accept it or not, when you heard of the name Bluetooth for the first time you must have thought of having a blue-toned tooth. It’s really funny to think of this matter now a day. Jokes apart, Bluetooth was named after King Harald Bluetooth, the king of Norway & Denmark from the 10th century. That’s all history, you all know about Bluetooth now, it’s one of the widely used wireless communication technology available now. It’s very common to find it in various communication devices like mobile phones, laptops, computer or any other wireless devices. Bluetooth lets you connect your devices without attaching any wire. For example, a wireless mouse, keyboard, gamepad or soundbox.

When it comes to technology, there is always a vast chance of improvement. Especially you can see this improvement in communication media. Bluetooth is a very important source of virtual communication, so it’s being improved day by day as well. Bluetooth often faced various criticism for some issues. According to the users, Bluetooth has an unstable connection problem, the file transfer speed is very slow, also it doesn’t have any special feature that can make it attractive for the users.

But things are changing, Bluetooth is being improved dramatically that may change the way you look at it. In January 2019, SIG (Special Interest Group) of Bluetooth has taken further steps ahead to improve Bluetooth. You can say it’s a renovation instead. They have launched Bluetooth 5.1, with some all-new features. But the question here is, are those features up to the expectations you have, are those features open the door of new opportunities? Let’s find out these answers & let’s see what it differs.

Bluetooth 5.1 Version:

Suppose you have forgotten any small device like your smartwatch, pocket speaker or earbuds which is connected to your device through Bluetooth. Isn’t it interesting if you can track those small devices & find the exact direction to those? Well, Bluetooth 5.1 lets you do the same.

Bluetooth 5.1 What’s New:

The main feature that differs Bluetooth 5.1 from other versions of Bluetooth is the direction signal. From the previous versions of Bluetooth like the Bluetooth 5.0, you can only see the distance of your connected devices by how strong the signal is. But Bluetooth 5.1 not just calculate the distance, it also shows the direction to your connected device. There are also some new features added to Bluetooth 5.1 which are stated below:

01. Direction Finding:

The personal experiences with this new feature may go beyond your expectations. Let you know about the Direction Finding feature broadly. Bluetooth 5.1 offers you two methods of direction-finding, AoA (Angle of Arrival) & AoD (Angle of Departure). It ensures that it can find out the direction from where the signal is coming from. It uses IQ ( In-phase & Quadrature) sampling method to determine the cycle of radio waves upon an antenna considering a specific time period. But to use this feature both AoA & AoD devices must have an alignment of multiple antennas.

This feature has opened the door of several opportunities, especially for the developers. Now the developers can develop Bluetooth based positioning systems including IPS (Indoor Positioning System) & RTLS (Real-Time Locating System) by using the direction-finding feature. If you don’t understand well any of these then let’s make you clear, if you lose your earbuds or keys or any other small device which enables Bluetooth 5.1, this feature will show the direction to the area of 1 inch where your device is. So no more look here & there & get mad when you lose your precious device, Bluetooth 5.1 is on the rescue.

02. Improved GATT Caching:

Gatt Caching or Generic Attribute Profile Caching helps in the Bluetooth connection process between two devices. Typically it starts when the connection process runs & it checks what the receiver device can support, the GATT service of that device, the characteristics & various structural values & details. All GATT devices include a database that sends a service discovery request to attain which are included in the database to set-up a connection. The database is also known as the attribute table which includes DII (Device Identifier Information). In Bluetooth 5.1, this GATT caching has been improved a lot compared to Bluetooth 5.0. It now allows any device to skip the discovery process & directly form a connection. Now you can retain the attribute cache from an untrusted relationship device.

03. Enhanced Bluetooth Advertising:

Bluetooth advertising refers to the way by which various Bluetooth devices let know that they are available to be connected. In the case of using Bluetooth, the most annoying thing is, trying to connect to a device several times but failing. You will be glad to know that Bluetooth 5.1 enhanced advertising features that avoid these types of problems by announcing that they are available for the nearest Bluetooth devices. Mainly, there are two types of major advertising enhancements which are included in Bluetooth 5.1. Those 2 types are discussed below:

Randomized Advertising Channel Index:

The previous versions of Bluetooth force Bluetooth devices to chronologically & strictly cycling through 3 specific channels, channel 37 or 38 or 39. The devices can not go beyond these. But Bluetooth 5.1 has a new feature which is known as a randomized advertising channel that avoids unchanging channel sequence & let the devices choose channels randomly. Which means when you are in an area where there are too many Bluetooth devices are active, randomized advertising channel index will help to avoid connection problem or connection interaction. Apps that use advertising to communicate with each other will be benefitted from improved scalability and reliability in busy radio environments. So your 5.1 Bluetooth devices can now select any channel which will minimize the probability of any advertising package distortion.

New Periodic Advertising Sync Transfer:

Another enhanced advertising feature of Bluetooth 5.1 is periodic advertising sync transfer. This feature provides the ability to synchronize the advertising scheme to the connection scanning when your device is connecting to other devices. This feature is also available in Bluetooth 5.0 which is known as SyncInfo. But in Bluetooth 5.1, it has been improved. The new periodic advertising sync feature allows less tractable devices to perform the synchronization process. It also helps to pass the required synchronization details over one point to another Bluetooth point.

This sync info contains each & every detail that the receiver device needs to know during synchronizing with the periodic advertising of your Bluetooth 5.1. The most common example for this is connecting your smartphone with your smartphone then pass the connection to your associated Bluetooth 5.1 included smartwatch. Thus your smartwatch can be benefitted from using periodic advertising & then scan required data from your smart TV as your device already know when to exchange any data.

04. Faster connection & Less Power Consumption:

The enhanced Bluetooth advertising allows your device to connect fast, transfer data fast & use less power. If you are having a device that has less power saving energy then the Bluetooth 5.1 will be very helpful. Though the changes from Bluetooth 5.0 to Bluetooth 5.1 are less in the count, those minor added features bring a great deal. As it has better GATT caching capability. So the data transfer will be faster than before with very minimum data distortion.

05. Other Extra Features:

Above are the most remarkable changes that Bluetooth 5.1 includes. But it’s not finished yet, Bluetooth 5.1 also has some other extra features that will be very handy for you. It includes ADI (AdvDataInfo) in scan response packages which are used in extended advertising packets. This latest version also includes an HCI command that lets the host tell the generic controller when to use the debug key values. The HCI command also allows the classifications of radio channels as “bad”.

There is also a new sleep clock accuracy update when you will move to Bluetooth 5.1. This added feature will use minimum power overnight. So no more tension to see your device with a low battery early in the morning. There is also a minor change which ensures the clarification during the interaction between QoS (Quality of Service) & Flow Specification. The Bluetooth 5.1 allows the SID to appear in the scan response reports as well.

So, what do you think about all these added features of Bluetooth 5.1? Maybe it’s time to upgrade your Bluetooth & enjoy all the new features, who knows, your prospect will change. But the thing is there are not available devices that include Bluetooth 5.1. The manufacturer will launch several devices by next year with Bluetooth 5.1. Now it’s mainly for the developers. So keep calm & wait to for the new version Bluetooth 5.2 and enjoy your own.

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jmfayard profile image
Jean-Michel 🕵🏻‍♂️ Fayard • Edited

@rahmantutul technical note:
the #help tag is confusing on dev.to
it means Please help me , not I help you.
What you are looking for is the tag #tutorial