New solutions appear on the market regularly, with fitness tracking watches, wellbeing rings, glasses, clothing, sports aids, headsets, motion gloves, and much more, all enabled by technologies such as GNSS GPS, cellular, UWB, BLE, WLAN and WPT. The topic of wearable equipment spans market sectors, such as sport, leisure, wellbeing, medical, commercial, and industrial control.
With the advancement of new technologies, such as 5G NR, global coverage and efficient energy use will further accelerate the rapid growth of wearable radio equipment. However, this rapid growth relies on the product’s ability to be co-located with other electrical and electronic equipment for satisfactory operation in its intended use, without degradation to the services it provides.
In niche applications, market share is won by having a quality product where cost isn’t always the main driver for product selection. Even in the case of consumer electronics, online customer reviews based on real product performance are the primary driver for most people.
Regulatory and industry approvals
Most regulators throughout the world impose some form of product regulation – these are mainly to protect us as consumers from a safety, health and environmental perspective. Still, increasingly industry groups and regulators also impose additional requirements to provide assurance covering user experiences, such as quality of service.
A common regulatory requirement limits the unwanted electromagnetic emissions emitted from products. These are mainly introduced to protect licensed radio communication services and serve as a way of removing products that cause interference. Tests are performed to assess the emissions before placing the equipment on the market, typically over the frequency ranges in which most communication systems operate. Historically this range has been up to 1 GHz. However, due to the rapid increase in mass-produced products operating at higher frequencies, this is now typically 6 GHz for many electronic products and even higher for any radio-enabled equipment.
With the advent of 5G in the GHz region (FR2) and higher frequencies for 6G (THz), this range is being reviewed. Clearly, there is a trade-off between the cost/time of testing and the radio services it seeks to protect.
As highlighted above, some regions of the world also specify immunity requirements for products. While this not a safety, health or environmental-related issue (as these aspects are covered by specific legislation), the immunity of the product to EMC interference has a fundamental impact on the reputation and brand of the product itself. A phone dropping a call or slow data, a smartwatch not communicating with the tethered phone or intermittent/loss of audio to your earphones are all examples of electromagnetic interference, either from other equipment or within the product itself.
Ensuring product performance through testing
Whether specified by regulation or by industry groups, the electromagnetic immunity of a product is critical. But testing isn’t just for testing’s sake. Its point is to simulate real-world environments at an R&D stage of the product’s design (and then validated at the end with certification tests) to provide manufacturers and suppliers with confidence that the product will not suffer poor performance in the real world.
Classic immunity tests simulate traditional known sources of electrical interference such as being located near other wireless devices, electrostatic discharge (ESD), electrical transients such as those from switching loads on/off, and the like.
In the case of new technologies and use cases for wearables, additional tests need to be considered since the way that we use these products is different from those traditional tests and the way that we use technology.
By way of an example, wireless coexistence testing simulates another wireless technology using the same or adjacent frequency bands in close proximity to one another. Imagine your ANT+ heart rate monitor (operating at 2.4 GHz) not working properly as it interferes with the Bluetooth (also operating at 2.4 GHz) for the audio connection. This miniature ecosystem relies on the technologies working in harmony with each other to ensure a good user experience.
Linking this with Over the Air (OTA) testing to simulate how a human body affects the antenna radiation pattern and path losses of this technology used on a person provides manufacturers with important information about their design and how to overcome these interference issues, and in turn produce a higher quality device.
How can Element help
Wearable connected devices provide new challenges to the consumer electronics industry. Element can help overcome these challenges through early R&D planning, compliance strategy, early-stage assessments, and final test and certification.
While not always specified by regulation or industry bodies, these additional, practical tests are a way of building and demonstrating the quality of a product. The majority of consumers and end-users would be happy to pay more for a product they know will work in the environment and ecosystem that it will operate.
Element has extensive capabilities to provide the testing services needed for small, connected equipment intended to be worn on the body.
The company can help guide customers through the regulatory and testing process to correctly get their wearable devices to market, including radio performance, antenna performance, OTA, RF Exposure and SAR, Hearing Aid Compatibility (HAC), EMC performance, product safety and battery safety.
In addition to its Telecommunication Certification Body (TCB) and Notified Body (NB) services, Element’s conformance testing and industry acceptance teams provide carrier acceptance, interoperability, and industry approvals.