Bluetooth 5.1 Angle of Arrival backward compatibility - bluetooth

I am currently designing a simple indoor location project to evaluate possibilities of Bluetooth 5.1 standard. The feature I would like to use is AoA (Angle of Arrival) introduced in Bluetooth 5.1.
According to the standard, AoA allows to measure position of a transmitting device (tx) by approximating the angle and measuring RSSI on a locator/receiver (rx). Since AoA is a feature newly implemented in 5.1, I understand that rx needs to support 5.1 Bluetooth standard. How about the transmitting device? What is the minimum version of Bluetooth it needs to support? Can I use 4.x BLE beacons (or Android/iOS devices simulating beacons) for this purpose?

The implementation uses an extended version of the advertisement data that contains a "Constant Tone Extension". Both devices need to support this feature in order to calculate the angle. So no you can not use old 4.x devices. Both devices must explicitly support this feature, and use it. Keep in mind that far from all Bluetooth 5.1 and 5.2 devices support this feature.

If you want to experience BLE AOA, not BLE 5.1 Direction Finding, you can create a special BLE frame on a BLE 4.2+ device. It can mimic the CTE frame, but the receiver side also needs to be able to handle this frame. It is not part of the 5.1 Direction Finding standard although.

Related

Can I send Bluetooth advertising packets with Constant Tone Extension from a smartphone?

Bluetooth 5.1 introduced the ability to include a "Constant Tone Extension" into an Advertising packet. On the receive side, a suitable device can perform Angle-of-Arrival estimation using this information. I have experimented with this technology using BLE EVK devices (Nordic).
My question is can I use a 5.1 compatible smartphone as the transmitter? How can I enable CTE in the advertising packet? Is it something that can be configured through a suitable app and android SDK, or do I need lower-level access to the phones Bluetooth modem (drivers)?
Thanks!
Since CTE is an optional feature for Bluetooth 5.1, the answer is clear: it depends.
Bluetooth direction finding is not yet supported by Android, so it would require a manufacturer-specific API to enable CTE (if it is supported by the smartphone hardware).

Bluetooth Classic 5.1?

I bought iclever bluetooth keyboard model:IC-BK10. On amazon, it shows bluetooth logo and "5.1". I assumed it uses Bluetooth 5.1
I try to capture Bluetooth Low Energy beacon on IC-BK10. But I cannot capture any BLE packet.
I asked customer support of iclever.
They replied
"Please be advised that not all Bluetooth 5.1 is Bluetooth low energy. Classic Bluetooth also has Bluetooth 5.1"
Is that possible Bluetooth Classic to have 5.1 feature?
The Bluetooth specification document (which is versioned 5.1, 5.0, 4.0, 3.0, etc.) applies to both Bluetooth Classic and Bluetooth Low Energy. In fact, the document is a reference for the specifications of both kinds of devices. So just because a device is listed as Bluetooth version 5.1, it does not mean it’s Bluetooth Low Energy compatible.
So to answer your question: Yes, a Bluetooth 5.1 device could be Bluetooth Classic, Bluetooth Low Energy, or even both (referred to as a Dual Mode device, best example is your smartphone).
This can be a bit confusing, so always refer to the manufacturer’s technical specs for the product or contact their support.
The version number of Bluetooth should just be interpreted as which year's Bluetooth specification was used when the product was created or qualified. In every new version, a bunch of optional features are added and features are seldom removed.
So never look at the Bluetooth version to figure out what features a device supports. Bluetooth Classic has not been removed in newer Bluetooth versions.
A Bluetooth 2.0 product can for example usually be re-qualified for the 5.1 specification without any changes needed in the hardware or software.

Does Bluetooth 5 implements BR/EDR natively?

I can't find a proper answer on the Internet.
The Bluetooth Basic Rate / Enhanced Data Rate (BR/EDR) appeared with the 2.0 Bluetooth Core Specification to improve data rate transfers. The Bluetooth Low Energy (BLE) appeared with the 4.0 Bluetooth Core Specification to improve consumption in the IoT field. Yet, to make those two modes work together (BLE & BR/EDR) you had to use a "Smart Ready" module (or dual-mode specific module).
Today, we have the Bluetooth 5. I don't quite understand if, when I browse Bluetooth 5 SoC on the market, the BR/EDR is implemented natively. For the BLE mode, it is. From a general FAQ :
Is the low energy feature of Bluetooth a part of Bluetooth 5.0?
Yes, Bluetooth with low energy functionality, introduced in Bluetooth 4.0, is a feature within Bluetooth Core Specification version 5.0. In fact, the new features and benefits of Bluetooth 5.0 are designed specifically for Bluetooth with low energy functionality.
But for the BR/EDR mode, the Bluetooth 5 Core Specification states (p323, Vol : 2 Core System Package [BR/EDR Controller Volume]) :
Two modulation modes are defined. A mandatory mode, called Basic Rate, uses a shaped [...]. An optional mode, called Enhanced Data Rate, uses PSK modulation [...].
So, from the Core Specification, the EDR mode is optional. Yet, I can't find any SoC or module (BT5 compliant) that has this EDR mode, like it doesn't exist anymore but everyone exhibit high data transfers (more than EDR used to be with previous version).
So, is the EDR implemented natively in BT5 (as the BLE is) even if the Core Specification states it as optional ?
Where am I wrong ?
Thanks !
"Most" things in the Bluetooth Core specification are optional. You can have a BT5-compliant Bluetooth Classic chip that doesn't have any LE functionality and you can have a BT5-compliant BLE chip that doesn't have any Bluetooth classic features.
To check whether a particular Bluetooth chip supports a specific feature, just look it up at https://launchstudio.bluetooth.com/Listings/Search.
As mentioned above, lots of things Bluetooth are optional, and the nomenclature is confusing and changeable.
Bluetooth Smart Ready describes modules that can do both Smart (ie LE) as well as classic. If you are looking for a Bluetooth Smart Ready module, we've successfully used the Silicon Labs (acquired Bluegiga) BT121 module in a couple of products where we needed SPP with high speed and range (BR/EDR).
Hope that helps!
Best Regards, Dave

Is Bluetooth 4.0+ BLE?

I am trying to identify which android phones support Bluetooth Low Energy and I am a bit confused on whether or not a device with BTv4.0+ is BLE compatible.
To be more precise, I am looking at the device Samsung Galaxy J5. According to http://www.gsmarena.com/samsung_galaxy_j5-7184.php, the bluetooth version is 4.1 but it doesn't mention anything about BLE.
According to the bluetooth specification:
"Bluetooth Low Energy (LE) (also called Bluetooth Smart or Version 4.0+ of the Bluetooth specification) is the power- and application-friendly version of Bluetooth that was built for the Internet of Things (IoT).". According to this I would presume that 4.0+ is BLE.
However if you see the specs of Samsung Galaxy S6 (http://www.gsmarena.com/samsung_galaxy_s6-6849.php) it mentions that it supports both BTv4.1 and BLE. It therefore distinguishes the two BT specifications.
Any information would be very helpful
Edit
Additional reference information for interested parties:
from bluetooth.org: Two flavors of Bluetooth The two most prevalent implementations of the specification are Bluetooth Basic Rate/Enhanced Data Rate (BR/EDR), which was adopted as version 2.0/2.1, and Bluetooth with low energy (LE), which was adopted as version 4.0/4.1/4.2. Each implementation has different use cases and each implementation uses a different chipset to meet essential hardware requirements. Dual-mode chipsets are also available for applications that include both use cases. - See more at: https://www.bluetooth.com/specifications/bluetooth-core-specification#sthash.7X7IrtWy.dpuf
Instead of relying on gsmarena with unreliable information, you can refer to Bluetooth SIG's official information.
Based on this Bluetooth SIG's announcement and this one, BLE is a core specification of Bluetooth 4.0. Bluetooth 4.1 and 4.2 also adopt this core specification.
However, all this still depends on whether the manufacturers implement the firmware. To keep track of all this, Bluetooth SIG maintains a list of devices currently supporting any profile (for example GATT).
This crossed my mind myself as I saw it as a pointless advancement until I saw the low energy bLE (bluetooth low energy) side of it. In my pastime I tinker with various electronics and with various BLE 4.x modules and their pro's and cons are HUGE.
All in all, BLE is better as Bluetooth pretty much is battery drain on the most robust of phones.
I found a nice little writeup (pretty simple yet comprehensive) here: http://www.argenox.com/bluetooth-low-energy-ble-v4-0-development/library/a-guide-to-selecting-a-bluetooth-chipset/
Do cut my answer short, as the bag you linked shows it as being "NFC" compatible, then yet, it's BLE 4.x. (That's Near Field Communication i.e. similar to your your contactless bank card). The v4.1, A2DP which you mention is how one "audio device talks to another" via bluetooth. (dvanced Audio Distribution Profile).
If you're really bored, there's a long list of other profiles (other than A2D):
https://en.wikipedia.org/wiki/List_of_Bluetooth_profiles
Hope this helps!
Happy bluetoothing!

Will Bluetooth 4.0 actually reduce battery drainage on smartphones?

One major drawback that always made me reluctant to using Bluetooth in apps was the battery drainage factor. With Bluetooth 4.0 and the low-energy hype, I've started to change my position. But after reading up on it more carefully, I've gotten the understanding that smartphones currently delivered with Bluetooth 4.0 run a so called dual-mode, implementing Bluetooth 4.0 capabilities ontop of a regular Bluetooth controller. This would mean that the battery drainage the Bluetooth controller would have on the device won't change much with Bluetooth 4.0 (note: I'm not interested in data transfer, just idle/scan).
My question:
Will a Bluetooth 4.0 supported smartphone be able to broadcast its device name and scan for other devices more energy efficiently than predecessing Bluetooth supported models?
If you are looking only for BT LE functionality, BT 4.0 will reduce battery drainage but as on smartphones they support both classic and LE, they will consume more battery for sure

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