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What is Bluetooth 5? 4.2? Bluetooth Classic? Bluetooth Smart? Low Energy? The naming is confusing, for sure.
The Bluetooth Special Interest Group (which sounds like a dental convention) announced Bluetooth 5 last June and officially adopted it in December. Or more formally, "The Bluetooth Special Interest Group officially adopted Bluetooth 5 as the latest version of the Bluetooth core specification this week." Unlike previous Bluetooth standards, there is no decimal point, so it is simply Bluetooth 5 and not 5.0.
When Bluetooth started, it was very short range, intended to replace short cables such as between keyboard and PC and, especially, between headset and cellphone (before we all decided that Bluetooth headsets did the opposite of make you look cool). That original Bluetooth went through several versions of the standard, gaining more capability. Although not an official name, this is also known as Bluetooth Classic.
By the way, you might wonder where the name Bluetooth came from. The original standard was initiated by Ericsson, back when they were still in the handset business. It was named after the anglicized version of the Scandinavian Blåtand who was the king that, according to legend, united the Danish tribes into a single kingdom. The Bluetooth logo (see at the start of this post) is apparently a bind rune merging Harald's initials (you can pretty much see the B on the right hand half of the logo). The name was intended to be temporary, a placeholder while they developed the standard, but by the time they got round to thinking about a "real" name, it had already caught on.
Meanwhile, there is also Bluetooth Low Energy, or BLE. To add to the confusion, this is (or was) marketed under the name Bluetooth Smart, although you will see BLE a lot still. There was a Bluetooth Smart logo, but that is apparently now being phased out. Almost all devices, like smartphones, are expected to implement both classic Bluetooth and LE/Smart so from a consumer point of view having both names is simply confusing. Very low-end IoT devices are expected to only implement LE. Of course, manufacturers of devices and IP have to be concerned with the difference, since they are incompatible. As is often the case, making it clean and simple for the end user results in increased complexity under the hood.
BLE was originally developed by Nokia, then marketed by Nokia and its partners under the name WiBree. It was then integrated into the Bluetooth standard 4.0 in 2010. It turns out that the first BLE-ready device to hit the market was the iPhone 4S. Note that BLE is not compatible with classic Bluetooth, although most devices (like that iPhone 4S) are expected to implement both standards, and the standards have been defined in a way that allows this.
I mentioned the Bluetooth SIG above. It is huge, with over 30,000 member companies, all of them developing Bluetooth products. Market predictions are that it will be in over one-third of IoT devices by 2020, and that over 370 million Bluetooth beacons will ship by then.
The two most important versions of the Bluetooth standard are:
The Bluetooth SIG identifies smart home, health, and sport/fitness as targeted sectors. These have extremely low power requirements with some devices expected to operate for "years" on a coin cell, along with severe cost constraints. The aim is to provide wireless connectivity to beacons and thus give internet connectivity (to the cloud) to devices that cannot afford, in terms of power and/or silicon budget, a full-blown connection.
Bluetooth 4.2 was announced at the end of 2014, with larger data packets, more security, and full support for internet connections including IPv6. The range remains the same but transfer speeds are as much as 2.5 times what they were before. It has both a classic and a LE variant, although most hub-like devices (such as smartphones) support both.
Bluetooth 5 (not 5.0, remember) was unveiled in London in June and was adopted last month. The headline capabilities are four times the range, twice the speed, and eight times the broadcast message capacity compared to 4.x versions. The next level of detail is that it also:
There is a low-energy version of the protocol, and it is backward compatible with the low-energy version of the Bluetooth 4.x.
Cadence has announced Bluetooth 5 VIP, the first in the market, and TripleCheck for Bluetooth 5. It also announced Bluetooth 4.2 VIP. Current designs are all (or mostly) Bluetooth 4.2, and future designs are likely to all (or mostly) be Bluetooth 5. The Bluetooth 5 VIP also supports Bluetooth 4.2. Verification is simplified with a single model for Bluetooth Low Energy (BLE) as well as Basic Rate/Enhanced Data Rate (BR/EDR). As always, Cadence VIP supports any simulator. There is no need to make methodology changes to take advantage of it.
Until now, companies developing Bluetooth products have been doing their own verification since there was no other option available. But that suffers from the usual issue that a misunderstanding of the protocol specification can get into both the design itself and the verification suite. It is much better to have independent verification from a different company. Although Bluetooth 5 devices are not expected to be available for another six months or so, VIP is available now during the design phase when it is first needed. The TripleCheck productivity tool, in particular, enables experts and novices alike to get to market quickly and have full confidence in the implementation of their Bluetooth product.
The VIP covers the controller, the PHY, and the PHY adapter. In more detail:
For more information, see the Bluetooth 5 VIP page. Or watch this five-minute video:
Everything seems to come with Bluetooth these days. How about your pressure cooker? What could possibly go wrong?
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