Ultra-wideband ( UWB, ultra wideband, ultra-wide band and ultraband) is a radio technology that can use a very low energy level for short-range, high-bandwidth communications over a large portion of the radio spectrum.[ USC Viterbi School of Engineering. Archived from the original 2012-03-21.] UWB has traditional applications in non-cooperative Imaging radar. Most recent applications target sensor data collection, precise locating,[ Ultra Wide Band (UWB) Development. Archived from the original 2012-03-21.]
Characteristics
Ultra-wideband is a technology for transmitting information across a wide bandwidth (>500
Hertz). This allows for the transmission of a large amount of signal energy without interfering with conventional
narrowband and
carrier wave transmission in the same frequency band. Regulatory limits in many countries allow for this efficient use of radio bandwidth, and enable high-data-rate personal area network (PAN) wireless connectivity, longer-range low-data-rate applications, and the transparent co-existence of radar and imaging systems with existing communications systems.
Ultra-wideband was formerly known as pulse radio, but the FCC and the International Telecommunication Union Radiocommunication Sector (ITU-R) currently define UWB as an antenna transmission for which emitted signal bandwidth exceeds the lesser of 500 MHz or 20% of the arithmetic center frequency.[ Characteristics of ultra-wideband technology] Thus, pulse-based systems—where each transmitted pulse occupies the UWB bandwidth (or an aggregate of at least 500 MHz of a narrow-band carrier; for example, orthogonal frequency-division multiplexing (OFDM))—can access the UWB spectrum under the rules.
Theory
A significant difference between conventional radio transmissions and UWB is that conventional systems transmit information by varying the power level, frequency, or phase (or a combination of these) of a sinusoidal wave. UWB transmissions transmit information by generating radio energy at specific time intervals and occupying a large bandwidth, thus enabling pulse-position or time modulation. The information can also be modulated on UWB signals (pulses) by encoding the polarity of the pulse, its amplitude and/or by using orthogonal pulses. UWB pulses can be sent sporadically at relatively low pulse rates to support time or position modulation, but can also be sent at rates up to the inverse of the UWB pulse bandwidth. Pulse-UWB systems have been demonstrated at channel pulse rates in excess of 1.3 billion pulses per second using a continuous stream of UWB pulses (Continuous Pulse UWB or
C-UWB), while supporting forward error-correction encoded data rates in excess of 675 Mbit/s.
A UWB radio system can be used to determine the "time of flight" of the transmission at various frequencies. This helps overcome multipath propagation, since some of the frequencies have a line-of-sight trajectory, while other indirect paths have longer delays. With a cooperative symmetric two-way metering technique, distances can be measured to high resolution and accuracy.[ Efficient method of TOA estimation for through wall imaging by UWB radar. International Conference on Ultra-Wideband, 2008.]
Applications
Real-time location
UWB is useful for real-time locating systems, and its precision capabilities and low power make it well-suited for radio-frequency-sensitive environments, such as hospitals. UWB is also useful for peer-to-peer fine ranging, which allows many applications based on relative distance between two entities.
UWB uses multiple techniques for location detection:
-
Time of flight (ToF)
-
Time difference of arrival (TDoA)
-
Two-way ranging (TWR)
-
Phase difference of arrival (PDoA)
While ToF and TWR focus on distance measurement, PDoA allows the system to estimate the Angle of arrival (AoA) by calculating the carrier phase shift across multiple antennas. When combined with ranging data, this enables precise 2D or 3D positioning using a single anchor, providing a critical technical foundation for mobile "follow-me" or applications and infrastructure-light tracking solutions.
Mobile devices with UWB capability
Apple launched the first three phones with ultra-wideband capabilities in September 2019, namely, the iPhone 11, iPhone 11 Pro, and iPhone 11 Pro Max.
Apple also launched Series 6 of Apple Watch in September 2020, which features UWB,
and their
AirTags featuring this technology were revealed at a press event on April 20, 2021.
The Samsung Galaxy Note 20 Ultra, Galaxy S21+, and Galaxy S21 Ultra also began supporting UWB,
along with the Samsung Galaxy SmartTag+.
The Xiaomi MIX 4 released in August 2021 supports UWB, and offers the capability of connecting to select
AIoT devices.
The FiRa Consortium was founded in August 2019 to develop interoperable UWB ecosystems including mobile phones. Samsung, Xiaomi, and Oppo are currently members of the FiRa Consortium.
Industrial applications
UWB is increasingly utilized in
auto-follow and
follow-me systems for autonomous mobile robots (AMRs) and smart vehicles. By integrating high-precision ranging with AoA/PDoA estimation, a mobile platform can autonomously track and follow a target tag in real-time. This methodology offers superior reliability in complex indoor environments where visual tracking may be compromised by lighting variations, occlusions, or identical target features.
Radar
Ultra-wideband gained widespread attention for its implementation in synthetic aperture radar (SAR) technology. Due to its high resolution capacities using lower frequencies, UWB SAR was heavily researched for its object-penetration ability.
Starting in the early 1990s, the U.S. Army Research Laboratory (ARL) developed various stationary and mobile ground-, foliage-, and wall-penetrating radar platforms that served to detect and identify buried IEDs and hidden adversaries at a safe distance. Examples include the
railSAR, the
boomSAR, the
SIRE Radar, and the
SAFIRE radar.
ARL has also investigated the feasibility of whether UWB radar technology can incorporate Doppler processing to estimate the velocity of a moving target when the platform is stationary.
While a 2013 report highlighted the issue with the use of UWB waveforms due to target range migration during the integration interval, more recent studies have suggested that UWB waveforms can demonstrate better performance compared to conventional Doppler processing as long as a correct
matched filter is used.
Ultra-wideband pulse have also been used to monitor vital signs of the human body, such as heart rate and respiration signals as well as human gait analysis and fall detection. It serves as a potential alternative to continuous-wave radar systems since it involves less power consumption and a high-resolution range profile. However, its low signal-to-noise ratio has made it vulnerable to errors.
Ultra-wideband is also used in "see-through-the-wall" precision radar-imaging technology,[Michal Aftanas Through-Wall Imaging with UWB Radar System Dissertation Thesis, 2009] precision locating and tracking (using distance measurements between radios), and precision time-of-arrival-based localization approaches.
Data transfer
Ultra-wideband characteristics are well-suited to short-range applications, such as
wireless USB, Wireless
video monitor,
, wireless
printing, and
to portable media players.
UWB was proposed for use in personal area networks, and appeared in the IEEE 802.15.3a draft PAN standard. However, after several years of deadlock, the IEEE 802.15.3a task group
was dissolved
in 2006. The work was completed by the WiMedia Alliance and the USB Implementer Forum. Slow progress in UWB standards development, the cost of initial implementation, and performance significantly lower than initially expected are several reasons for the limited use of UWB in consumer products (which caused several UWB vendors to cease operations in 2008 and 2009).
[ Tzero Technologies shuts down; that's the end of ultrawideband , VentureBeat]
Autonomous vehicles
UWB's precise positioning and ranging capabilities enable collision avoidance and centimeter-level localization accuracy, surpassing traditional GPS systems. Moreover, its high data rate and low latency facilitate seamless vehicle-to-vehicle communication, promoting real-time information exchange and coordinated actions. UWB also enables effective vehicle-to-infrastructure communication, integrating with infrastructure elements for optimized behavior based on precise timing and synchronized data. Additionally, UWB's versatility supports innovative applications such as high-resolution radar imaging for advanced driver assistance systems, secure key less entry via biometrics or device pairing, and occupant monitoring systems, potentially enhancing convenience, security, and passenger safety.
UWB products/chips
| +
! Supplier
! Product name
! Standard
! Band
! Announced
! Commercial products |
| Microchip Technology | ATA8350 | LRP | 6.2–7.8 GHz | Feb 2021 | |
| Microchip Technology | ATA8352 | LRP | 6.2–8.3 GHz | Feb 2021 | |
| NXP | NCJ29D5 | HRP | 6–8.5 GHz | Nov 12, 2019 | |
| NXP | SR100T | HRP | 6–9 GHz | Sept 17, 2019 | Samsung Galaxy Note20 Ultra |
| Apple Inc. | U1 | HRP | 6–8.5 GHz | Sept 11, 2019 | iPhone 11, iPhone 12, iPhone 13, and iPhone 14, Apple Watch Series 6, Apple Watch Series 7, Apple Watch Series 8, and Apple Watch Ultra, HomePod Mini and HomePod (2nd generation), AirTag (1st generation), and AirPods Pro 2 |
| Apple Inc. | U2 | HRP | 6–8.5 GHz | Sept 12, 2023 | iPhone 15 and newer (excluding iPhone 16e and iPhone 17e), iPhone Air, Apple Watch Series 9 and newer, Apple Watch Ultra 2 and newer, AirTag (2nd generation), and AirPods Pro 3 |
| Qorvo | DW1000 | HRP | 3.5–6.5 GHz | Nov 7, 2013 | |
| Qorvo | DW3000 | HRP | 6–8.5 GHz | Jan 2019 | |
| 3dB Access | 3DB6830 | LRP | 6–8 GHz | | |
| Ceva | Ceva-Waves UWB | HRP | 3.1–10.6 GHz depending on radio | Jun 24, 2021 | |
| SPARK Microsystems | SR1010/SR1020 | N/A | 3.1–6 GHz, 6-9.25 GHz | Mar 18, 2020 | |
| Samsung Electronics | Exynos Connect U100 | Unknown | 6489.6 MHz/ 8987.2 MHz | Mar 21, 2023 | |
Regulation
In the U.S.,
ultra-wideband refers to radio technology with a bandwidth exceeding the lesser of 500 MHz or 20% of the arithmetic
center frequency, according to the U.S. Federal Communications Commission (FCC). A February 14, 2002 FCC Report and Order
authorized the unlicensed use of UWB in the frequency range from 3.1 to 10.6
Hertz. The FCC power
spectral density (PSD) emission limit for UWB transmitters is −41.3 dBm/MHz. This limit also applies to unintentional emitters in the UWB band (the "Part 15" limit). However, the emission limit for UWB emitters may be significantly lower (as low as −75 dBm/MHz) in other segments of the spectrum.
Deliberations in the International Telecommunication Union Radiocommunication Sector (ITU-R) resulted in a Report and Recommendation on UWB in November 2005. UK regulator Ofcom announced a similar decision
There has been concern over interference between narrowband and UWB signals that share the same spectrum. Earlier, the only radio technology that used pulses was spark-gap transmitters, which international treaties banned because they interfere with medium-wave receivers. However, UWB uses much lower levels of power. The subject was extensively covered in the proceedings that led to the adoption of the FCC rules in the US, and in the meetings of the ITU-R leading to its Report and Recommendations on UWB technology. Commonly-used electrical appliances emit impulsive noise (for example, hair dryers), and proponents successfully argued that the noise floor would not be raised excessively by wider deployment of low power wideband transmitters.
Coexistence with other standards
In February 2002, the Federal Communications Commission (FCC) released an amendment (Part 15) that specifies the rules of UWB transmission and reception. According to this release, any signal with fractional bandwidth greater than 20% or having a bandwidth greater than 500 MHz is considered as an UWB signal. The FCC ruling also defines access to 7.5 GHz of unlicensed spectrum between 3.1 and 10.6 GHz that is made available for communication and measurement systems.
Narrowband signals that exist in the UWB range, such as IEEE 802.11a transmissions, may exhibit high PSD levels compared to UWB signals as seen by a UWB receiver. As a result, one would expect a degradation of UWB bit error rate performance.
Technology groups
See also
External links
