by Mahendra Tailor, Technology Leader, Laird Technologies
Bluetooth® 5 is a lot like the last upgrade I got to my smartphone. Does the latest phone have a lot of new bells and whistles that are pretty darn neat? Yes. Are all of those new features going to be useful to certain users? Yes, but there’s no way that all the new functionality is relevant to me. I’m mostly interested in a select few features and apps, and the rest don’t impact me directly. In fact, it’s best if I just focus on the stuff I need because it’s so easy to get overwhelmed and distracted by the thousand things the phone can do.
The same is true for the updated Bluetooth 5 standard. The marketing messages are working overtime to try to convince engineers that everything in Bluetooth 5 is not just exciting…but essential. It’s effective marketing, but it is still marketing. For the vast majority of engineers, only a subset of new capabilities in a standard like Bluetooth 5 are truly “must haves” that need engineers’ attention immediately. Other capabilities are less relevant today or may remain irrelevant into the future—a great example of which is the “Included Services” feature that has been part of the standard since release 4.0, but that no one would likely consider critical.
Why is it important to differentiate between the “must have” features and the “don’t really need them” features? For the same reason as the newest phones: because learning and utilizing everything new can be a distraction from just mastering what you truly need. Engineers do not have unlimited time and unlimited resources. When a new standard like Bluetooth 5 comes out and their company asks the engineering team to start integrating that into products, engineers need to be selective.
The reality is that adopting everything in a new standard like Bluetooth 5 would bring engineering timelines to a standstill, particularly since so many features are not even “exposed” to engineers as upper host stacks are being updated. A perfect example of this is the lack of access to advertising extensions, which are not available to engineers 10 months after the specification was released. Tackling everything in the new standard would involve a lot of waiting, resulting in a needless standstill. The reality is that some aspects of Bluetooth 5 will not be relevant to you, depending on what kind of project you are working on and how a given product will be used by the end user. This is especially the case now, before Bluetooth 5 is a standard feature on iPhones, Galaxys and other smartphones. To save time, money and your mental health, it’s therefore important to simplify things by navigating past certain features and focusing on the ones that are most important for your design projects.
So what are the most important new features in Bluetooth that wireless engineers and product designers should have their eyes on?
- Do Take Advantage of Greater Range…but it’s No Free Lunch – One of the traditional limitations of Bluetooth is the relatively short reach of the signal compared to other wireless technologies. That meant sticking to use cases where the range was within the same room, for example with a consumer product. Bluetooth 5 redefines that radius of signal performance with a range that is up to 4x as far as previous versions of Bluetooth. This may be the single most important feature for engineers to look at and integrate into their project pipeline because greater range is such a highly valued trait by end users, allowing companies to market products in new ways. For example, Bluetooth-powered audio equipment for consumers could be upgraded with connectivity that works throughout an entire home. But that added range comes at a cost: leveraging that additional range could potentially reduce the battery life of your device by a factor of 8—meaning that a device that previously lasted a year in the field might now only last six weeks. It’s critical for your team to understand how Bluetooth 5’s additional range can fit into your design projects, and it is just as critical to understand the inverse relationship with battery life so you can make smart decisions about when and how to leverage this capability.
- Do Leverage the Larger Payloads for Beaconing…but be Patient – One of the enhancements in Bluetooth 5 that I get asked about most often is the far greater data payload that is possible. The new standard can deliver physical packets that are 10x the size than was previously possible and logical packets that are more than 50x larger, which is such a significant increase that it allows engineers to do far more with beaconing than ever possible before. In the past, the packet length limitations made beaconing largely a fun feature, but not a truly practical one for many use cases. That is all changed in Bluetooth 5 with payload sizes that make beaconing functional rather than just fun. The use cases for this range from utilizing beaconing to enable more robust initial set-up processes when a device is first pulled out of the box and turned on, enabling initialization for both consumer and industrial products to be far more automated without requiring active management by the end user or by professionals. The more robust beaconing payloads also make it possible to expedite repairs and maintenance by delivering far more information via beaconing reports. One aspect of this that is particularly intriguing is the broadcast audio capability in Bluetooth 5, which could be used to provide audio beacons rather than a typical phone notification. But be forewarned that even 10 months since the announcement of the new standard, this beaconing feature is not yet available for engineers, even for labs that are typically way ahead of the curve. So this will be a great feature to explore, but you may need to wait a bit before it is fully available.
- Don’t Worry about Security, if… – This may be the first time anyone has ever said “Don’t worry about security” in a technical article about IoT design. As every reader of this magazine knows, security is a fundamental concern with wirelessly-enabled devices. Recent headlines about IoT security breaches make that abundantly clear, but what many engineers don’t realize from the marketing propaganda about Bluetooth 5 is that there is nothing new security-wise in the new protocol. The major security enhancements to Bluetooth were in the 4.2 release, and those enhancements still hold their own today. Typically, the process of understanding and integrating new security features into design projects is one of the most time-consuming aspects of adopting new standards like Bluetooth 5. In fact, it’s so time-consuming that some engineers might lean toward holding off on Bluetooth 5 adoption simply to delay the difficulty of that process. The bottom line for engineers, though, is that there are no substantive security changes in Bluetooth 5 as long as you and your engineering team were already utilizing Bluetooth 4.2.
- Do Check Out Speedier Data Transfer…and the Positive Impact on Battery Life – This aspect of Bluetooth 5 is a godsend for phone manufacturers in particular, but is also relevant to engineers working on a broad range of devices where battery life is critical. Bluetooth 5 includes a new 2 Mbps physical layer that allows information to be sent in half the time possible in previous versions of Bluetooth. Why is that important? Because half the time means half the power used to transmit that data. That is a dramatic savings that engineers should understand because of how profound the impact is on energy usage. It’s important to note that comes at a cost of 30% reduced range, but that is largely irrelevant for many consumer devices and even many industrial devices that are deployed in clusters rather than spread out in a deployment that pushes the bounds of Bluetooth’s range.
- If You are Working on Mesh Projects, Do Look Closely at the Milliseconds – That’s a question I get asked a lot because so many engineers want to know what impact Bluetooth 5 will have on mesh-related projects. The short answer is that Bluetooth 5 is going to have a positive impact on mesh deployments because beacon adverts can be as fast as every 20 milliseconds with the new standard versus 100 milliseconds or more with the previous release. Engineers who are working on mesh projects will love that news because the faster rate is far better aligned with what they need for projects. I should be sure to note that BLE mesh projects do not require Bluetooth 5 (Bluetooth 4 is adequate for supporting those projects), but the speed advantage in Bluetooth 5 will be worth looking at closely for engineers working intensively on mesh designs.
- Do Check out Modules for Faster Deployment – When engineers get the directive to integrate a new standard like Bluetooth 5, speed is usually of the essence because companies want to beat competitors to market with products that can have the new standard emblazoned on the packaging. To claim Bluetooth 5 compatibility and seize that first-to-market advantage, use certified RF modules that are designed for Bluetooth 5 to dramatically accelerate the design process versus complex RF design work. Not only does it reduce the necessary design work, but these Bluetooth modules also allow companies to avoid the time-consuming process of securing FCC certification, which can bog down product delivery timelines in ways that turn potentially successful projects into failures when they finally get to market.
Naturally, there is no one-size-fits-all strategy for how engineers should evaluate and adopt Bluetooth 5, but my hope is that this quick cheat sheet of recommendations provides a starting point that gives engineers a roadmap for the new standard and puts them in the driver’s seat to determine what they truly need in the near term—and earn that promotion and raise in the process.