5G is a test vendor’s dream-mission – critical and difficult. 5G promises to ignite T&M again. And it is very difficult: mmWave, massive MIMO, huge bandwidths, challenging processing, and a race to deploy. And one can throw IoT (Internet of Things) in as well. 5G can rearrange the market leaders in RF and communication test.
5G features new technologies such as massive MIMO and mmWave. Both technologies use multiple antennas and beam-forming, which is a huge departure from current and previous wireless architectures. 5G also includes new wireless control mechanisms that split the control and data to facilitate the concept of network slicing, which scales the level of service to an individual user device.
In addition, the standards proposed for 5G are far more complex than 3G and 4G standards. 5G will transform our networks, so the industry must transform the way these systems are designed, developed, and tested. For algorithm design, simply modeling systems without any real-world validation has not been enough for an idea to advance from concept to production. For test, traditional methods that focus on an individual component will not be able to account for the overall impact to the system.
Test and measurement solutions will be key in the commercialization cycle, asserts NI. Test systems must expand beyond the physical layer to quickly and cost efficiently test these new multi-antenna technologies with controllable/steerable beams. Additionally, these systems must address the new mm Wave-capable devices with extremely wide bandwidths. These test solutions must not only be able to test the important parameters of a device but also be cost-effective for 5G to reach its potential and achieve widespread adoption.
With these characteristics, 5G requires a different approach to test for wireless devices and systems. For example, system-level over-the-air (OTA) test must become standard in the 5G ecosystem. OTA test presents several challenges but perhaps the most daunting pertains to the environment in which the test equipment and the device under test must coexist. Air is an unpredictable medium, and the channel itself varies over time and environmental conditions. Wireless test engineers must isolate the channel in the OTA scenario and control the device on a per beam basis to effectively test the device.
In addition, companies like Intel have introduced early phased array antenna modules featuring an antenna attached directly to the RF front end to minimize system losses. Because access to the device is limited, the test equipment must step up in frequency to the mmWave bands and characterize key performance metrics beam by beam.
Finally, whereas bandwidth is a familiar test challenge, the tested bandwidth of 5G is expected to increase 50× over a standard LTE channel. At these bandwidths, test systems must not only generate and acquire wider bandwidth waveforms but also process all that data in real time.
What is next. Wireless researchers have embraced a platform design approach using SDRs to expedite the early research phase of 5G, and they have delivered. Now, test solution providers must do the same. 5G presents a paradigm shift the likes of which we have never seen before, and a platform-based approach that is flexible and software configurable will be essential to the development of this ecosystem.
ETM manufacturers will face increased demands for greater capabilities and lower costs. As a result, test products for 5G will be far more complex than those of generations before. Looking beyond individual components to chipsets and system solutions is helping manufacturers squeeze more performance out of limited space and lower cost targets – something especially demanded of modular instrumentation. At the same time, this high level of integration, as well as the increased signal chain count required for MIMO and beam-forming, is putting even greater demands on power. By working with suppliers, especially those with the broadest portfolio of products, it is becoming possible to better engineer components into complete signal chain solutions to meet the demanding performance, power, space, and time-to-market requirements of tomorrow’s instrumentation, comments Analog Devices.
IoT, the Second Key Driver
The IoT is already here. From fitness wearables to medical applications to smart farming and smart cities, millions of devices already are connected to cellular, Wi-Fi, Bluetooth, and other wireless technologies. Millions more are being developed and planned in both the consumer IoT space and in industrial IoT.
IoT testing is a hot topic, but still a tiny part of the overall testing market. Frost and Sullivan’s findings indicate that this niche market in particular reached USD 178.7 million in 2016, growing at 6.2 percent compared to the previous year. Testing for IoT is being driven by the need for security, interoperability, battery management, and electromagnetic emissions management.
In addition, testing for IoT is also being boosted by new and emerging standards as well as the wide variety of wireless technologies that can be used to connect devices, according to Kimbara, noting between new and legacy RF formats, there are more than 60 technologies that companies can use to connect IoT devices, ranging from the personal network level for wearables, local area networks such as the home, neighborhood-range technologies, and wide area networks that would include low power networks and cellular, among others.
Keysight Technologies, Rohde & Schwarz, Anritsu Company, National Instruments, and LitePoint are the top five participants in the global T&M market for IoT wireless applications.
New form factors, standards, and communications demands unique to IoT are forcing adaptation in wireless device testing. Change tends to come slowly, filtered through standards and certification bodies, but it is happening.
Although the standard equipment – power meters, signal generators, spectrum analyzers – is often the same with IoT RF testing, there are some physical shifts in test set-ups. One of the main trends in IoT test evolution is that the physical forms of IoT devices demand new test approaches. Wireless testing was designed for smartphones, tablets, laptops, dongles, and other “traditional” wireless devices, and that sometimes means a poor fit (literally) for devices that range in size from connected vehicles to small sensors.
To address large form-factor devices, which have one physical dimension greater than 42 cm, wireless trade association CTIA recently released a new test plan that relies on a reverberation chamber (which enables a complex test environment of radio signal reflections) rather than the traditional anechoic or semi-anechoic chambers that absorb signal reflections and provide a very controlled and isolated view of radiated performance. Reverb chambers allow for more flexible testing because they do not require exact positioning within the chamber and can accommodate heavy or bulky items; they also typically tend to be less expensive than anechoic chambers and are currently the only measurement methodology for the large form-factor test.
Standards proliferation and fragmentation is also impacting IoT test. While cellular standards have been produced by 3GPP and Wi-Fi standards under the auspices of IEEE, IoT encompasses a large and growing number of unlicensed, mostly short-range technologies. The cellular industry has responded with the development of Cat-M and narrowband-IoT designed to provide low-power licensed spectrum options for IoT. Verizon Communications has said it expects to have an IoT network available by the end of this year. However, test equipment for Cat-M and NB-IoT does not yet exist, although network equipment and devices are already in field trials, according to Art Miller, senior director of business development for smart cities and industrial IoT at Qualcomm, which is participating in some of those current trials. Miller said this means tests have to be conducted with actual network equipment and user devices rather than test equipment that can emulate them.
Consolidation in standards may not happen within the next three to five years, so that within a vertical there may be one or two commonly deployed technologies.
Key takeaways. New form factors and wireless technology choices are driving physical and logistical changes to testing for the IoT. Emerging standards are making a concerted effort to allow testing to be more efficient and cost-effective for devices that do not fit the traditional smart-phone or tablet cost models.
The cost and time involved with testing are major barriers to IoT development and adoption, influencing everything from technology choice to time to market. It also may disadvantage cellular compared to other wireless technologies, due to cost and complexity.
Companies interested in the IoT space would do well to consult RF experts early on in their development and design processes, particularly to avoid common pain points such as antenna design issues and RF noise from neighboring components that can cause certification failures, increase time to market, and result in costly retesting, advises Kelly Hill, RCR Wireless.