The Next Generation of Wearable Technology
The market for wearable electronic devices has undergone dramatic growth over the last decade, from a small starting point in 2010 to a major segment of the electronics industry. Precise figures vary, but a CAGR in excess of 20% seems common to most reports with an overall market size of multiple billion dollars under a broad definition of the sector.
Read the article in Electronics Weekly - page 26-27
First generation wearables
The first generation of wearables fell into two main categories, either quite simple devices such as basic fitness trackers or highly complex ones including advanced Smart Watches.
As the market has developed, the high-end segment has consolidated around a few major brands, the obvious ones being Samsung and Apple. The investment behind these devices is significant, requiring custom “System in Package” designs, in some cases unique semiconductors and, as such, is only possible for those companies with deep pockets.
At the other extreme, the initial wave of wearables was quite simple, often consisting of little more than a BLE (Bluetooth Low Energy) device with an integrated microprocessor and a few sensors.
BLE was the crucial foundation technology for the wearable explosion. Classic Bluetooth, whilst functionally capable, was simply too power hungry to make devices that met ease of use requirements. Few people were interested in something that needed daily charging. Other low power radio technologies were available but needed some other device to connect to. BLE solved these issues, allowing wearables with a time between recharge measured in weeks rather than days, that could easily connect to any phone on the market and send data onward to the cloud if required.
Despite their relative simplicity, a wide variety of devices could be conceived based on a BLE radio/microprocessor connected to some sensors. Simple fitness trackers were amongst the first entrants to the market, but many of the more interesting solutions were focussed on niche applications with their value based on smart data analysis more than advanced electronics.
Products under the wide-ranging “health and wellness” heading vary from the somewhat gimmicky (connected toothbrush, anyone?) to medically certified devices aimed at assisting people with serious medical conditions such as continuous glucose monitoring devices. There are companies with $Bn businesses based almost exclusively on electronic glucose monitoring wearables. Between those extremes, there are devices to assist people with fertility, better sleep, monitor heart function or even control your mood.
New technologies, new opportunities
However, technology never stands still. The simple fitness tracker has been made almost redundant through the integration of most of the features inside a phone. Meanwhile the Bluetooth devices that triggered the market have become increasingly sophisticated, enabling new possibilities.
The latest high end BLE devices have dual core processors, floating point processing, a much expanded I/o capability, and run real time operating systems. The BLE standard itself has evolved, offering higher data rates, longer range, better locating capabilities and low power audio. Nor is BLE the only radio technology available – LoRa (Long Range) offers low powered wide area network capability and UWB (Ultra-Wide Band) is featuring in high end smartphones to enable high precision location functions.
What this means for designers is that they are much less constrained by calculating power, connectivity limitations or the number of sensors or other peripherals they can connect to a still relatively low-cost central unit.
A less welcome challenge is posed by malevolent actors for whom any electronic device is just another challenge to hack. Spying on one’s step count might be harmless – but interfering with a glucose reading or heart monitoring device could cause serious harm. To counter this kind of threat, the latest generation devices have enhanced security features which were not available on the older generation of devices. ARM Trustzone blocks are now available on high end BLE devices, which permit secure key storage and advanced end to end encryption and authentication. Embedded secure elements like those in SIM or bank card represent a further level of hardware security. There will be increased focus on such capabilities as wearables advance in the medical domain, to protect sensitive data as well as active interference in the operation of a device. Wearables may also integrate financial capabilities, meaning the wearer needs be protected from fiscal as well physical harm.
More precise location
Location services are another new frontier in wearable capability. Crude indoor location was already availably with BLE and used for “find me” tags but had limited accuracy. The Bluetooth 5.1 standard enhanced locating capability by adding “Angle of Arrival” capability, whereby a locating antenna “Anchor” array can track enabled BLE devices more closely. This can be used to locate people or physical assets in a building, for example.
UWB driven positioning has been available for quite some time but has been hampered by a lack of standards or widespread adoption, meaning only complex and closed proprietary systems can really take advantage. First generation devices were also rather power hungry, limiting appeal. However, new situations are leading to innovative applications. For example, our company developed a "Security Bubble Covid-19," an electronic device which helps implement social distancing in crowded environments including workplaces.
All these factors are now being addressed with standards driven by industry wide bodies, a newer and higher performing generation of chips and – most important of all – the appearance of UWB on the highest end phones, notably from Apple and Samsung. Should this technology follow the same path as BLE in terms of becoming a widespread feature of phones, then a whole range of location and authentication based wearable devices can be envisaged. For example, a UWB based device could remove the need to use a card to pass a gate in the metro, or for access to a building. It could also be used to track people in dangerous places – for example on a building site or firefighters attending an incident with real time information on where everyone is.
The most immediate impact of BLE Audio will be simply to provide more power efficient music devices – headphones and earbuds – that can last longer between charges. It also offers additional high end features such as multicasting, so multiple parties can receive synchronised audio. People will no longer need to share one earbud each. Longer term, the ability to stream data may find other creative applications in devices where the power-hungry nature of classic Bluetooth meant it was not well suited. Audio is not the only application for streaming capability – humans can, in many situations, be remarkably sensitive to latency in response, and such a capability could also have applications in haptic response devices such as game controllers. The Sci-Fi vision controlling computers by swiping in the air is not so far away.
Fast-moving, innovative future
Wearables have come a long way from the simple step counter, but there is no sign the growth trend is slowing down. The technology is moving fast, and user acceptance is growing, so what was something once only worn by “geeks” is becoming conventional and unremarkable. Smart glasses, for example, got off to a bad start with adverse publicity, but are returning in more sombre and focussed forms, and will undoubtedly become widespread in a variety of professional and personal settings.
The challenges in wearable design will remain – packing as much technical capability as possible into a small space and making creative and intelligent use of data to offer real value to users. There are technical issues involved in handling radio transmission close to the body as well. But a new generation of core components is nonetheless spurring an exciting wave of innovation in the field.
By: Nick Wood, VP Sales & Marketing and Chris Barratt, CTO, Insight SiP