After the read, you will know:
- What is spatial perception?
- A-GNSS system architecture
- What is UWB?
- Compared with Wi-Fi and Bluetooth positioning technology, UWB’s advantages
- Comparison of UWB and other positioning technologies
- UWB industry development
- Conclusion
Yesterday, Xiaomi officially released the one-finger UWB technology, which attracted widespread attention from the entire network.
According to the introduction, based on this one-finger connection technology, mobile phones, and smart devices will have spatial perception capabilities, just like indoor GPS. When the mobile phone is pointed at the smart device, the control card will automatically pop up, allowing direct control.
Can Xiaomi's consecutive fingers completely ignite the UWB consumer market?
Point the phone at the fan, the phone will pop up a quick control card, turn on the fan with one click
Point the phone to the TV, and the phone becomes a TV remote control, and it can also cast the screen with one click
That’s right, this UWB is the UWB that was launched simultaneously when Apple released the iPhone 11 on September 11 last year.
At that time, all iPhone 11 series were equipped with U1 chips supporting UWB technology.
Apple has said that the U1 chip will significantly enhance the spatial awareness (Spatial Awareness) capabilities of Apple’s iPhone. Through the Airdrop (airdrop delivery) application, Apple also demonstrated fast file sharing based on UWB technology.
When Apple’s autumn press conference last month, it was also revealed that Apple’s Apple Watch Series 6 will be equipped with U1 chips and ultra-wideband antennas to achieve spatial perception capabilities.
So the question is, what is spatial perception? What kind of technology is UWB? In addition to spatial perception, what else can UWB do?
What is spatial perception?
The so-called spatial perception ability is the ability to perceive orientation. A more direct point is positioning ability.
Using UWB technology, mobile phones, and smart devices can achieve more accurate indoor positioning, not only can sense their own location but also the location of other nearby mobile phones or devices.
Speaking of positioning, I believe everyone is familiar with it. We often use apps such as Baidu Maps, which have positioning and navigation services.
Location services help us to grasp location information, indicate directions, increase our sense of security and control, and bring great convenience to our work and life.
So, what is the difference between UWB technology and the positioning technology we use now?
Our most commonly used positioning technology now is satellite positioning.
Satellite positioning is a technology that uses artificial earth satellites to measure points. Its characteristics are very obvious, that is, high precision, fast speed, and low cost.
The well-known GPS, Beidou, etc., belong to the Global Navigation Satellite System (GNSS), which can provide satellite positioning services.
In order to better eliminate errors and improve response speed, GNSS will introduce some space-based or land-based auxiliary methods. GNSS combined with auxiliary means is also called A-GNSS.
The more commonly used A-GNSS now transmits enhanced correction data through land-based mobile communication networks, provides auxiliary information, strengthens and speeds up the search and tracking performance and speed of satellite navigation signals, shortens positioning time, and improves positioning accuracy.
A-GNSS system architecture
Both GNSS and A-GNSS have an obvious shortcoming, that is, indoor positioning cannot be achieved. The reason is obvious, satellite signals will be blocked by buildings.
However, with the development of the times, there are more and more business scenarios for indoor positioning, and users’ demands for indoor positioning are becoming stronger. Such as underground garage navigation, shopping malls to find shops or companions, and even children lost and found.
As a result, some people began to try to use various short-distance communication technologies to develop high-precision indoor positioning systems to cater to user needs and make small money. The available technologies include Wi-Fi, Bluetooth, UWB, etc.
What is UWB technology?
Everything is familiar with Wi-Fi and Bluetooth. What is UWB?
UWB stands for Ultra-Wideband, ultra-wideband technology. It originated from the pulse communication technology that emerged in the 1960s.
Those who understand communication know that the general communication system uses a high-frequency carrier to modulate a narrowband signal and the actual bandwidth occupied by the communication signal is not high.
UWB is different from traditional communication technology. It realizes wireless transmission by sending and receiving extremely narrow pulses with nanoseconds or microseconds or less. Due to the extremely short pulse time width, ultra-wideband in the spectrum can be achieved: the bandwidth used is above 500MHz.
The FCC (Federal Communications Commission) has allocated a total of 7.5 GHz from 3.1 to 10.6 GHz for UWB and has also imposed stricter limits on its radiation power than FCC Part 15.209, limiting it to the -41.3 dBm frequency band.
In short, this technology enables fast data transmission at low power consumption levels through ultra-large bandwidth and low transmit power.
Due to the extremely short time width of UWB pulses, high-precision timing can also be used for distance measurement.
Compared with Wi-Fi and Bluetooth positioning technology, UWB has the following advantages:
1) Strong anti-multipath ability and high positioning accuracy
The bandwidth determines the distance resolution capability of the signal in a multipath environment (in direct proportion). UWB has a wide bandwidth and strong multipath resolution capability, which can distinguish and eliminate most of the effects of multipath interference signals and obtain highly accurate positioning results.
UWB can be higher than other traditional systems in distance resolution, and its accuracy can even reach more than a hundred times that of traditional systems such as Wi-Fi and Bluetooth under complex environments.
2) High time stamp accuracy
The bandwidth of the ultra-wideband pulse signal is on the order of nanoseconds. When calculating the position by timing, the error introduced is usually less than a few centimeters.
3) Strong electromagnetic compatibility
UWB has low transmitted power and wide signal bandwidth, which can be well concealed in other types of signals and environmental noise. Traditional receivers cannot recognize and receive and must use the same spreading code pulse sequence as the transmitting end for demodulation. , So it will not cause interference to other communication services, and it can also avoid interference from other communication devices.
4) Higher energy efficiency
UWB has a radio frequency bandwidth of more than 500MHz and can provide great spread spectrum gain, making UWB communication systems more energy efficient. This means that for battery-powered equipment, the operating time of the system can be greatly extended, or under the same transmission power limitation, the coverage is much larger than that of traditional technologies.
Generally, in short-distance applications, the transmit power of UWB transmitters is generally less than 1mW; in long-distance applications, a distance of 200 meters can be reached without an additional power amplifier, while achieving an air rate of 6.8Mbps.
Based on the above technical advantages, UWB can form a high-precision indoor positioning system.
What is UWB Comparison of other positioning technologies？
At present, there are three commonly used UWB ranging methods, namely:
(1) TOF (Time of flight): The distance measurement is achieved by measuring the flight time of the UWB signal between the base station and the tag.
(2) TDOA (Time Difference of Arrival): UWB signal is used to locate the time difference from the tag to each base station.
(3) PDOA (Phase Difference Of Arrival): Use the angle of arrival phase to measure the azimuth relationship between the base station and the tag.
What is UWB industry development
Before 2002, UWB was widely used for military purposes. In 2002, the FCC (Federal Communications Commission) imposed strict power restrictions on UWB as mentioned above before lifting the ban on UWB technology and allowing it to enter the civilian field.
Since then, UWB technology has entered a period of rapid development, and various technical solutions have also launched fierce competition around the formulation of UWB international standards.
In 2007, IEEE standardized the UWB technology in the 802.15.4a standard. After nearly ten years of development, UWB standards are constantly improving.
To achieve better spatial perception, the support of applied ecology is needed. In order to build the entire application ecosystem, the devices of different manufacturers need to achieve interoperability and compatibility. It is foreseeable that in the future, equipment from all manufacturers will likely support the IEEE 802.15.4 standard.
There are also a large number of small and medium-sized entrepreneurial teams in China engaged in the development of UWB solutions, mainly for indoor high-precision positioning and smart home, smart park, smart factory, and other scenarios.
What is UWB Conclusion
We are accelerating towards the era of the Internet of Everything. Although 5G is a hot topic now, 5G cannot take all IoT scenarios. Short-distance communication technologies represented by Wi-Fi 6, Bluetooth, and UWB still have a lot of room for development and market opportunities. These technologies can be closely integrated with subdivided IoT scenarios according to their own characteristics to provide users with a better service experience.
Besides the What is UWB article, you may also be interested in the below articles.
4G vs 5G: What is the difference between 4G and 5G?
How to Choose the Best Antenna for Lora?