Wireless and Precise: Q&A with DecaWave
Virtual reality, bike safety, and self-parking vehicles all have something in common, and so do the automotive, industrial and consumer applications turning to impulse radio ultra wide band innovations for micro-location.
This month Research and Markets introduced its “Global Real Time Location System-Forecast and Trends (2015-2020) report . Among the report’s findings: The Real Time Location System, or RTLS, market is anticipated to reach USD 3612.56 million by 2020. Ultra Wide Band (UWB) resides under the RTLS umbrella, along with RFID, WiFi, Bluetooth Low Energy, Zigbee and others. Research and Markets defines Real Time Location Systems as “systems which are used to locate and track assets or people in real time with the help of Radio Frequency (RF) signals as the communication medium.”
And ABI Research is predicting a shake-up in the RTLS and asset tracking markets, naming “innovators like Bluvision, Decawave and UWINLOC ” among the companies that would foment market disruption. ABI Research further notes, according to the firm’s Principal Analyst Patrick Connolly, “For the first time, enterprises don’t have to choose between high accuracy, low cost, and ease of deployment.”
EECatalog recently took the opportunity to speak with the chief marketing officer of Decawave. A fabless semiconductor company, Decawave announced earlier this year that it had reached one million Impulse Radio Ultra Wideband (IR-UWB) chips shipped. Edited excerpts from the Q&A follow.
EECatalog: Could you please put IR-UWB, a micro-location technology based on Time-of-Flight, into context for us by providing a bit of history?
Luc Darmon, Decawave: Earlier attempts to accomplish precise location used methods based on measuring the RF power at a point in space and assuming a correlation between the electromagnetic field and distance to the access point.
This method requires a lot of “fingerprinting” work because you have to measure the field in many areas of the room so that you build a 3D matrix of the field [thus allowing you to] correlate with the distance. But [with the method just described] there are a number of drawbacks. First, the precision is not there. Second, as soon as you have another person or another object in the room the fingerprinting is definitely wrong, and people have to find algorithmic ways to compensate, which are fairly heavy and power consuming.
For those transitioning from methods not based on Time-of-Flight to those based on Time-of-Flight and to using impulse radio ultra wide band (IR-UWB) to measure the signal’s time of flight, there are considerations related to the technology itself. For example, if you measure the signal’s time of flight from one object to another object, if you have an obstruction like a wall or another person, you have to assume that signal is slowed down, so the distance displayed will be larger—so you have to architect your system in a way such that you take into consideration the elements of this new technology.
Now, though, people are past the point of questions such as “what is this new technology and how does it work?” I think the market now understands there is no way to do location precisely other than with IR-UWB.
EECatalog: When you look at the various verticals, consumer, industrial, automotive with which IR-UWB is catching on, what are you particularly noticing?
Darmon, Decawave: Our technology can be considered standalone, and that is what is happening in most of the industrial cases. In other applications, such as consumer, for example, our IR-UWB technology pairs with another, such as sensor fusion and such things as accelerometers and gyroscopes.
And they have achieved great results. A company in the U.S. has developed a virtual reality helmet that is getting half-a-centimeter accuracy with our chip plus that company’s sensor fusion technology. The solution resolved an issue that some people have with virutal reality, motion sickness, because “what they see is not what they see,” and they are solving that by showing on the screen the location of the person within the room. So the individual wearing the helmet sees the location and that resolves the motion sickness problem.
Regarding trends in automotive, the first application that will be using our technology and chip will be secure car access. There have been a lot of articles in the press talking about the “relay attack,” where somebody picks the signal from your key fob and relays it to an accomplice who is close to your car who can then open the car.
Another trend is valet parking or convenience parking. Our technology doesn’t do the parking function, but we do a function that is mandatory with regard to the law. If the car parks itself without the driver in the driver’s seat, it has such required functionality as acoustic radar, vision systems, and cameras, but what it doesn’t have is the notion that the driver has to be in line of sight or in total control of the car when the car is parking itself because of potential accidents. The driver has to be legally responsible for his car. Our chip measures the distance between the driver [holding the key fob] and his car and the car would be allowed to move only if the driver is within a certain distance of the car.
Other markets under research right now include wireless sensors that work with RF inside the car not only to reduce the number of cables and connectors, but also to get rid of some weight in the car.
Trends include efforts to come up with solutions for collision avoidance for bicycles and pedestrians—it is not radar because radar has a short range, [rather] the pedestrian or cyclist would wear a tag. The tag can be seen, and the distance can be measured from the car [followed by] a warning: Careful, a bicycle is coming your way [or to indicate] how many meters away the bicycle is.
While what’s noted above is being looked at now, it involves a lot of other system considerations beyond the chip itself.
EECatalog: Anything to add before we wrap up?
Darmon, Decawave: The technology in the chip is very versatile in terms of configurations and architectures. One can do a lot of different things in different systems with it. It’s a building block that people can use for doing different things and different architectures.