UWB - The New Short-Range Networking Standard in 5G Applications

As the planet upgrades to 5G, connectivity will be an increasingly important factor in consumer electronics and industrial implementations, ranging from smartwatches and laptops to inventory management systems and commercial fleet monitoring. The fast, safe, and reliable wireless transfer of data will be essential to the Industrial Internet of Things (IIoT) and other commercial applications, as well as public utilizations like traffic management systems and intelligent streetlight controls. Wi-Fi and Bluetooth are the standard wireless communications protocols traditionally implemented in connected devices. Still, signal degradation and interference can become issues with Wi-Fi/Bluetooth in signal-saturated environments. More connected devices mean more signals and more interference, leading developers to look for other signal protocols to help improve wireless connectivity. Developers may have found an answer to the connectivity conundrum by looking to the past. 

Ultra-Wideband (UWB), a wireless transmission protocol developed in the early days of radio, is being revived to augment current wireless protocols and improve the efficiency and reliability of short-range data transfers. UWB is defined in the US as radio signals with a bandwidth greater than 500 MHz or with a fractional bandwidth (a measure of how “wide” the transmission band is) greater than 20%.

The larger bandwidth enables much faster upload and download speeds while reducing susceptibility to signal interference and hacking compared to traditional, narrowband signals like Wi-Fi. UWB is also more energy efficient, less costly than Bluetooth, and, although UWB's range is limited, is an appealing alternative in short-range data transmission scenarios. This article will explore the past and present of UWB and where it might fit into the interconnected world of the future.

The Origins of Ultra-Wideband

The genesis of UWB can be traced back to the first wireless radio signal devices that utilized "spark gap" transmitters to communicate wirelessly. The devices could transmit sound through short electrical impulses over short distances, which eventually led to radio wave transmission. In its infancy, UWB sent old-fashioned telegraph signals over large distances, such as messages to ships at sea. As the technology evolved, the higher frequency ranges UWB operates in made it an optimal method of transmitting large amounts of data, such as images or video files, over shorter distances.

UWB might have become the original wireless communication standard, but it was outlawed for commercial use in 1920, becoming a proprietary protocol for classified government and military implementations. UWB remained out of bounds for public use until 2002, when the Federal Communications Commission in the US opened the range between 3.1 and 10.6GHz back up for unlicensed use in commercial applications.

Since then, UWB has propagated into various technologies, including radar and location/positioning systems, medical devices and wearables, and consumer electronics. Apple included UWB tech in the iPhone 11 (released in 2019), enabling far more accurate positioning and ranging capabilities than previous iterations. UWB has also been implemented in SAR (synthetic aperture radar) technology applications, mainly in military scenarios. SARs object-penetration capability enables it to detect and locate improvised explosive devices that have been buried or hidden from sight, saving soldiers from walking, or driving into traps.

Where Ultra-Wideband is Now

The ongoing transition to 5G has been an inflection point in the adoption of UWB into networking and communication technology. UWB signals are transmitted either in short, quick pulses (measured in picoseconds) like the spark gap transmitters of old or in carrier waves like radio frequency (RF). Data transferred in pulses is transmitted by alternately turning the signal on and off—like the way lighthouses used to communicate with ships off the coast by flashing signals in Morse Code. It can require over a hundred pulses to transmit a single bit of data, but the high rate of speed at which the bits are transmitted (each pulse lasts fewer than 1.5 nanoseconds) enables data rates of up to 27 Mb/sec.

Carrier waves can also be created by modulating the signal to simulate an RF wave. UWB can transmit data over multiple frequencies at once and achieve much higher data rates than other wireless technologies. Implementing UWB with 5G networks can provide customers with faster upload/download speeds and greater bandwidth. 

UWB is also the optimal solution for real-time tracking and positioning applications, whether they're in consumer electronics (like the iPhone), used to manage inventory, or to determine the location of products or equipment within a factory/manufacturing setting as shown in the figure below.

A 5G-connected factory management network (Image Source: Blue Planet Studio / Stock.Adobe.com)

UWB-enabled devices come equipped with MIMO (multiple-input/multiple-output) antennas miniature enough to fit into devices as small as smartphones or watches. When two UWB-enabled devices are in close enough proximity to connect, the devices begin "ranging," or determining their respective locations and distance from one another through a method called "time of flight."

By sending a pulse from one device to another and measuring the time it takes the pulse to complete its journey, the two devices can determine their exact locations relative to one another. This is especially advantageous in indoor settings where GPS isn’t always as functional, and Wi-Fi can struggle to break through solid objects and surfaces. If you're the type who's always misplacing their phone or who can never find the TV remote, UWB can pinpoint their respective locations in your home within inches.

Due to its short transmission period and small packet size, UWB is also found in applications that require lower latency and faster system response times, like gaming and training simulations. UWB's low spectral density also helps prevent signal interference and makes UWB signals very difficult to detect, providing more security for data transmission. UWB's additional protection is already incorporated into digital car keys. Companies like BMW and Tesla are reportedly developing digital car keys that implement UWB for their vehicles to reduce incidents of signal relay theft from key fobs that transmit traditional radio signals. 

The Future of UWB – Where Can It Go from Here?

The most obvious potential is applications requiring high data transfer speeds, such as real-time video streaming. Security camera and traffic camera networks can provide higher-quality video using UWB than other wireless communication protocols. UWB's lower latency makes it a good potential fit for vehicular automated driving systems cameras. To avoid collisions with other moving vehicles, automobiles with automated driving systems will be able to share locations, speed, and direction instantaneously. 

Other wireless protocols may be subject to signal interference or latency delays. This kind of data sharing between vehicles can also improve overall traffic flow and fuel efficiency by suggesting alternate routes to avoid delays, keeping traffic moving steadily, and improving gas mileage. Sharing data between vehicles and general infrastructure is another potential benefit—ever been stuck driving around the big city on the weekend and can't find a place to park? A system by which parking structures communicate to motorists where and when open parking spots are available could make circling the block ten or fifteen times a thing of the past.

Personal medical devices can also be improved by implementing UWB, creating a personal wireless area network around a patient. Their heart monitor can communicate with their smartwatch to give the patient (and potentially doctors) real-time updates on the health of their heart. Forecasting heart attacks and other cardiac events could be greatly aided by having access to health-related data in real-time. 

Its object-penetration capabilities may also make UWB microwave imaging a new weapon in early cancer detection. Malignant tumors have different microwave signatures than normal, healthy tissue. By transmitting UWB pulses to a specific part of the body and then recording how long it takes the pulses to return (similar to RADAR measuring distance by transmitting and receiving radio waves), technicians can develop a two or three-dimensional image and determine if any malignant tumors are hiding behind the surrounding tissue. Body composition and variability in the type and consistency of the surrounding tissue can affect the quality of the resulting images, but microwave pulses being transmitted and received from multiple angles can help improve image resolution. UWB microwave imaging scans for breast cancer are being developed, and several have reached the clinical trial stage, while similar scans for skin cancer and brain tumors are in earlier stages of development.

UWB's most significant potential, however, may lie in mesh networks which are ultra-connected systems with multiple devices constantly exchanging data as shown in the figure below.

A mesh network of devices, vehicles, and infrastructure in a smart city (Image Source: Lesley Wang / Getty Images)

These mesh networks will allow devices to connect and automatically exchange and receive data. AI-powered algorithms might even be implemented to optimize data transmission by finding the fastest, most power-effective, lowest-latency path available. Data will flow through these networks the way electrical current flows through a resistance network, automatically finding the optimal path as the resistance increases or decreases. In implementations that require connected devices to be constantly in motion—for example, on a factory floor or a busy highway—these inter-connected systems could dramatically improve efficiency and responsiveness while providing greater security from interference or hacking than narrowband signals. 

Conclusion

Despite its other potential use cases, the key factor in UWB’s wider adoption will be connectivity. UWB isn’t an optimal alternative to other signal protocols in every scenario – but it can be a way of taking the burden off the narrowband spectrum while providing greater bandwidth and reducing signal interference in short-range, high-speed data transference. Utilizing UWB in local area networks for large uploads/downloads will free up Wi-Fi and Bluetooth to perform other operations while reducing consumer costs and energy consumption. 

UWB's efficacy won't just be local, but global. UWB will also play a big part in a 5G-connected world, where phones, tablets, medical wearables, GPS systems, and even cars are continuously changing, sharing data over enormous digital mesh networks. Its highly accurate geo-location capabilities make it an apt solution for commercial asset tracking and management systems and GPS tracking chips in cell phones and automobiles.

Vehicles that share traffic information with each other, heart monitors that transmit data to medical centers in real-time, phones that communicate which line to stand in to get through airport security the fastest… all with more precision and lower latency than Wi-Fi or Bluetooth. As 5G connectivity spreads all over the globe, look for UWB to grow as well.