February 25, 2015
By: Ben Wilmhoff, Founder and President, BluFlux –
Ultra-wideband technology, or UWB, is a radio technology used for high bandwidth, short-range and low-power communications as well as low-power imaging radar applications. It traces its roots to the work done by the well-known electrical and communications engineer, Robert Scholtz.
Canonical UWB Waveform which obeys FCC Spectral Mask
The principal advantages of UWB are for use in Wireless Personal Area Networks (WPANs), which are networks that connect other personal devices together either directly or through a hub node. Because of their wide instantaneous bandwidth, UWB radios support high data throughputs over relatively short distances with low power levels. WPAN applications include wireless USB and Wireless Media (“WiMedia”) applications; for example, wirelessly connecting your HDTV to the DVD player and the speakers to your radio receiver.
UWB signals are defined as occupying the lesser of 500 MHz or 20 percent of the arithmetic center frequency. Their unlicensed usage was authorized by the Federal Communications Commission (FCC) in 2002 between 3.1 and 10.6 GHz with strict limits on power density (-41.3 dBm / MHz), so as to avoid interference with other licensed emitters and receivers in this band.
UWB shows up in a few standards bodies and alliances from the 2000’s. In 2002, the Wimedia Alliance was formed to develop technology and standards for short range multi-media file transfers with ~500 Mbit/s datarates, using the UWB spectrum.
The IEEE 802.15.3a standard specifies a high speed enhancement to the 802.15.3 WPAN standard using UWB. The IEEE 802.15.4a group was formed to add precision ranging and location to the 802.15.4 family. UWB was one of two PHY layers chosen (the other being chirp spread spectrum in the unlicensed 2.4 GHz band).
Unfortunately, the Wimedia Alliance unraveled due to a technical loggerhead between two sets of industries represented by the Alliance, blocking the chance of UWBs to make a presence in a widely-adopted consumer product. The IEEE 802.15.3 working group was also disbanded as a result.
Notwithstanding, UWB lives on but is serving purposes other than low-power, short-range, high-datarate radio transmission. UWB is most widely used as a ranging radio for precise real-time location tracking. Companies like Decawave, Alereon, Bespoon, Ubisense, and Time Domain Corporation offer modules to complete real-time location systems (RTLS) for one- and two-way ranging for use in cell phones, factories, healthcare and even on the battlefield.
Novelda is a Norwegian company with a line of UWB low-power radar chips, modules and systems for detecting moving and static objects. Novelda’s network of partners and VARs includes Flat Earth Engineering, a Montana-based company,that both resells Novelda’s reference designs as well as integrates the Novelda ICs into sensors for weather, agriculture and other applications.
UWB in its various forms is an impulse radio technique that requires careful processing and management of the short-duration, high-bandwidth pulse to enjoy maximum benefit. A critical part of a UWB system design requires understanding the impulse response of the antenna(s), and how this parameter can dramatically affect the time resolution that a received waveform can be processed.
Today, BluFlux is working with several UWB systems companies on the design of tiny, high-performance UWB antennas that preserve the fidelity of the transmitted and received pulse waveform, and we’ve built an all-star team of experts to support UWB projects.
Although UWB has had its challenges, the potential applications for UWB across many industries are exciting, to say the least.
Interested in learning more? Contact our team to see how we can help bring your UWB projects from concept to market.