Ultra-wideband (UWB) is a radio technology for the transmission of data which allows a communication with high bandwidth and a low energy level for short-range. These features allow the technology to have a very high data throughput and high precision for location devices.
There are multiple cases of application for this technology but one common way to use it is for positioning systems. When we think of positioning systems, the GPS technology immediately comes to mind. It is true that GPS is fairly good and is widely used. However, it suffers from one major flaw : it is not exactly accurate when it comes to ranging. Indeed, the precision error is about several meters so this cannot be used for indoor positioning. The UWB offers a solution to this problem since its precision error is about 10 centimeters.
The indoor positioning matter is getting more and more attention nowadays since people realize the potential it can represent. Indeed, we can imagine several ways to put it to use:
- Industry : In a warehouse or a construction site, tracking the machinery or vehicles can be used in robbing cases.
- Marketing purpose : In a supermarket or commercial center for example, tracking/recording movements data to know which places are more frequented can be valuable.
- Indoor navigation system : In a museum for instance, implementing a system allowing the visitor to have a custom visit route depending on his tastes.
These are some of the possible applications of this technology and certainly not the only ones.
Decawave created a chip/module using this ultra-wideband technology called DWM1000 (DW1000 for the chip). It is a UWB compliant wireless transceiver which is optimised for indoor precision for Real Time Location Systems.
Before proceeding to the detailed examples, we will briefly explain the principle behind this ranging application. The system requires at least two DWM1000 modules since we will estimate the distance separating them. One of them will be the anchor, the supposedly stationary module, and the other will be a tag, the moving one. The modules will exchange messages through UWB transmissions and calculate the distance between them by looking into the times of arrival of the different messages. This is how it basically works.