Being a huge consumer electronics nerd, I watch tons of tech review videos every day. Average presenters say, “It has Bluetooth 5.0”, and that’s usually the end of the story (sometimes I hear “better connectivity, less lag”, good enough). As simple as it sounds, the sentence does the job of delivering this piece of information that is literal to the product, as if you already know what Bluetooth 5.0 actually is. At the end of the day, do you know anything further than just the version number on the spec sheet?
Below, I will attempt to make my very best guess about what the above products (shown in the banner) are without looking at their spec sheet. Then I will dive deep into its official spec sheet, and possibly proceed to the datasheets for the electronics and technology whitepapers for a detailed understanding. Hopefully, I will learn a lesson more than just numbers and how electrons flow in a circuit.
(spoiler: read till the very end for my major takeaway)
Fun fact: Where’s the name from
The name “Bluetooth” is beyond the color and the little pieces of rigid organic substance inside your mouth. Bluetooth is named after an old Scandinavian king who died over 1,000 years ago. Harald “Blåtand” (aka Bluetooth in English) Gormsson was a Viking king who ruled Denmark and Norway for 27 years since 958 AD. King Gormsson was known for his dead tooth that had a very dark shade of blue.
Fast forward to the recent years, In 1996, Intel, Ericsson, and Nokia were collaborating and working towards establishing a single wireless standard. While all the representatives were gathering at the Ericsson plant in Lund, Sweden, Intel representative Jim Kardash suggested “Bluetooth” to be the temporary codename. The reason was written in his own blog,
“King Harald Bluetooth … was famous for uniting Scandinavia just as we intended to unite the PC and cellular industries with a short-range wireless link,”
Now the logo. I guess, instead of a verbal explanation, a picture of ancient Nordic runes tells the story better. (hint: Harald Bluetooth)
True Wireless Earbuds
First I would like to investigate a recent purchase of mine, the JLab EPIC AIR ANC TRUE WIRELESS EARBUDS. Why TWS earbuds? I guess everyone loves them.
My guess
As I can remember, and also I presume, it has to have at least Bluetooth 5.0, as it is a very recent product that came out last year. 2020 is probably the year where all the true wireless earbuds bloom. 2 years back, I bought a pair of Samsung Gear IconX (2018 ver w/ Bluetooth 4.2). It is my first pair of true wireless earbuds. For the past 5 years or so, for typical Bluetooth speakers/headphones, there were all sorts of options packing different Bluetooth versions of hardware in different price ranges. However, as true wireless earbuds were not even a thing, where the Gear IconX was still positioned to be sports wearables, they were plenty expensive, as they had already got the most cutting edge tech in them. However, in 2019, there were much more options around which packed different Bluetooth hardware in different price ranges. A year later, 2020, even for some very budget-friendly options, they were all packed with Bluetooth 5.0. As consumers, we win.
In the year 2021, I don’t really care about if the product comes with the latest Bluetooth version as much as I did. Old Bluetooth devices tend to work less reliably, where there might be connection issues, serious audio latency issues, or sometimes unacceptable audio hiccups. Whereas, newer Bluetooth devices, (probably after 4.X I guess) start to work very well with virtually no issues.
Anyhow, I am here to dig deeper into the device.
Looking up the site
After reading the product description from their official website, I can confirm that this pair of true wireless earbuds have “Class 1 Bluetooth 5” (I have no idea what class one is). Not only it has active noise cancellation(ANC), it has its movie mode, which is advertised to lower your audio latency even more (i guess this is very much related to the wireless transmission?). Through the proprietary app, you can customize the EQ profile of the audio. Lastly, it has Dual Connect, where you can connect either earbud independently seamlessly.
Class 1 Bluetooth 5?
According to Wikipedia. The Class 1 Bluetooth has the most millWatt (mW), decibel-milliWatt (dBm), and a range of approximately 100 meters far. For a bigger picture to compare, 1mW is equivalent to 0.001W. Usually, a 5V 1A wall charger gives a 5W output. So the power consumption of these earbuds is actually very low (my gut feeling without too much accurate calculation).
For the Bluetooth 5.0 part. A major improvement is being made to the BLE part of it. BLE was introduced back in Bluetooth 4.0. When it was still 4.2, audio was still being transmitted via Bluetooth Classic. However, Bluetooth 5.0 is capable to transmit audio via just BLE.
p.s. The Apple Airpods use Bluetooth 4.2 for audio, and also the W1 chip for a better connection.
SoC?
To my understanding, most known brands use Qualcomm SoC (system on chip) for their true wireless earbuds (except Apple uses the W1, and sometimes Realtek). With some deeper google searching, I found out that the SoC on this pair of earbuds is actually from Airoha, a manufacturer from Taiwan. Specifically, the SoC model is 1552. According to the official spec sheet, this chip is stated to have
- Bluetooth 5.0 dual-mode including low energy profiles
- A2DP profile version 1.3 compliant
- HFP profile version 1.7 compliant
- HSP profile version 1.2 compliant
- AVRCP profile version 1.6 compliant
- SPP profile version 1.2 compliant
Things are starting to get fun here.
- A2DP = Advanced Audio Distribution Profile defines how high-quality stereo audio can be streamed from one device to another over a Bluetooth connection
- HFP = Hands-Free profile designed to enable a two-way wireless speaker-phone to be used with a Bluetooth phone.
- HSP = Handset Profile provides support for headsets to be used with mobile phones and gaming consoles.
- AVRCP = Audio/Video Remote Control Profile is designed to provide a standard interface to control TVs, Hi-fi equipment, etc
- SSP = Serial Port Profile emulates a serial cable to provide a simple substitute for existing RS-232, including the familiar control signals.
As far as the complaint version goes, the higher the number usually means more functions/improvements are provided on top of the previous version.
Wireless Computer Mouse
Second, I am looking into computer mice, which is the same subject matter as I have for my thesis at NYU ITP.
My guess/understanding
The mouse of choice is the MX Master 3, which is the successor of the mouse I personally own, the MX Master 2S. Still, I would love to see if there are major hardware upgrades, so I have chosen this new model to study.
As advertised to be the best productivity mouse on the market, it is capable to do both Bluetooth and 2.4 GHz wireless communication. From my previous experience of making my own BLE mouse, I know that BLE is capable to be a computer HID (human interface device), including a mouse/keyboard. So I would assume this very advanced mouse is havingat least BLE capabilities or say at least Bluetooth 4.0. As for the 2.4GHz wireless technology, it has been around for a long while before Bluetooth mice became a thing. And to my technical understanding and also personal experience, the 2.4GHz technology tends to run much more stable and quicker than Bluetooth.
Lastly, I still remember that my MX Master 2S didn’t work with a PC that has no built-in Bluetooth, but a very inexpensive Bluetooth dongle. A friend of mine told me, “your PC is not Bluetooth Smart”. Anyhow, I got around with the dongle and forgot about the Bluetooth Smart thing.
More Googling
According to Logitech’s official site, the tech spec says “Bluetooth low energy technology required”. I tried to look further for the actual answer, but I had no luck. What I can conclude is, it has a Bluetooth version above 4.0.
Bluetooth Smart
Meanwhile, the statement “BLE required” provides a little hint about why my mouse was not working with my PC. And I found out that
Bluetooth Smart Ready devices are considered dual-mode devices because they can communicate with both BLE devices and classic Bluetooth devices. Bluetooth Smart devices are considered single-mode devices because they cannot communicate with classic Bluetooth devices. Smart devices always enjoy the benefits of low-energy operation. Classic Bluetooth remains unchanged.
https://www.digikey.com/Web%20Export/Supplier%20Content/Laird_776/PDF/laird-wireless-bluetooth-smart-ready.pdf
So essentially, a Bluetooth Smart Ready device is capable of utilizing both BLE and Classic function from Bluetooth 4.0.
Advanced 2.4GHz Wireless Technology
Such technology emerged back in 2009 when I am trying to reference a white paper of such technology. At the same time, Logitech also introduced their Unifying technology. They advertise “their technology is different from conventional 2.4 GHz and 27 MHz wireless technologies” (I have never heard of 27MHz before). Probably, what is shown in the below table might not be accurate anymore, as it was dated 10 years ago, where Bluetooth evolved a lot in these 10+ years. Still, I would agree that their technology is better in the response time aspect.
Smart Door Lock
Last but not least, I would like to study a new product which I’ve never owned, but I’ve used once, which is the August Smart Lock.
My guess
The only time that I was physically interacting with this lock was dated half a year ago, the time when I visited my tech-savvy cousin’s house in California. These kinds of door locks don’t make much sense in NYC, as most people live in apartments that have a doorman. Still, I would like to have one if that works for my purpose someday.
My uncle and I arrived at my cousin’s home before he came back from grocery shopping. He reminded his dad to get in with the app on his phone. That didn’t work at the very beginning. I tried to troubleshoot and turned Bluetooth back on. Luckily we heard the motor spinning after pressing a big red circle on the app.
That said, the most essential part of this smart lock is Bluetooth but not Wifi. And it is very possible that it has BLE capabilities, as the door lock is supposed to function for a long period of time without charging very often. I guess it is also possible to enable Wifi capabilities by installing a hub/bridge/gateway, that truly connects this lock to the internet.
The answer, and a rather complicated scene
I think I am correct, the model that he owns is the basic August Smart Lock. Not the Pro, not the Wifi Smart lock, and he doesn’t have a gateway either (or he would have unlocked the door remotely for us).
Specifically, on its official site, it says “The August Smart Lock uses Bluetooth Energy (BLE) technology encryption, as well as an additional encryption mode.” As I know nothing about BLE encryption standards, I would like to scratch the surface a little bit.
BLE uses the AES-CCM cipher with 128-bit key length to provide data encryption and integrity over the wireless link. AES-CCM is a FIPS 140–2 approved cipher and is also used for security in other popular applications such as WiFi WPA2 and TLS 1.3. According to recommendation of NIST, 128-bit key length is considered secure until 2030.
The key is generated using Diffie-Hellman method with elliptic curve cryptography (ECC). Each device generates the same AES-CCM key at its end using the ECC public key received from the peer and its own secret ECC private key. ECC is a modern technique that provides strong security with small public-key sizes.
https://www.networkcomputing.com/wireless-infrastructure/iot-security-using-ble-encryption
All the options
From a customer’s point of view, this is a chart of confusion that intimidates them. But what I see from the comparison chart is how the designer (and possibly the engineer too) approached the IoT aspect of the product.
The biggest lesson
After making 3 functional PCB projects in a year, and especially my latest low power binary watch project, I’d say the greatest lesson I learned is the importance of striking a balance between technical and UX decision: to design the PCB constrained by the physical space and power limit while creating the best experience for the users.
A certain combination of the tech incorporated always has its pros and cons. For instance, a stand-alone “Wi-Fi Smart Lock” that doesn’t require a separate gateway makes the setup process easier and quicker for the users. Likewise, less hardware communication means less likely that they would lose connection. But power consumption becomes a concern as the device has to constantly listen to the internet using Wi-Fi.
The other way round, the basic BLE-powered “Smart Lock” has very limited features, which is definitely a downside for consumers. Although the users can always buy the “Wi-Fi Bridge” later on, more setup is again required. I can envision that, specifically for this case where the lock is already set up a long time ago, the process of adding the bridge to the system might be less reliable and controllable (from what I experienced with Xiao Mi Home devices), which is potentially a bad user experience. But this way, the power consumption constrain is rather dispensable, as BLE on the lock consumes very low power, while the bridge has constant power from the wall.
Very possible, August the company had already gone through the same thought process that I had, and they created these products with those concerns in mind while trying its best to minimize them for ultimately a great product. And it is good for the acquainted customers to purchase what they really need, according to the options provided by August. More than just “Bluetooth” on spec sheets.
