UWB Technology

Sequitur is based on the ultra-wideband (UWB) radio technology.

UWB is based on the transmission of very short radio pulses, that propagate in the environment. The precise computation of the time-of-flight (propagation time between a transmitter and a receiver) is the enabling technique making positioning possible with high accuracy. Knowing the propagation time means knowing the distance between a transmitter and a receiver; then, multiple measures can be fused to determine uniquely the position of a device.

UWB radio and the Decawave chipset allow these precise time-of-flight measurements (i.e., timestamping of the transmitting/receiving instants on radio signals) thanks to the very large bandwidth adopted. In fact, the large bandwidth ensures the capability of determining precisely where the radio signal starts and its time-of-arrival, with picoseconds accuracy (10 ps corresponds to 3 cm due to the speed of light in air).

Time-of-arrival (TOA) measurements are used in our positioning architectures based on Time-Difference-of-Arrival (TDOA) and Two-Way-Ranging (TWR). These techniques result in enhanced accuracy with respect to traditional schemes based on proximity or on the analysis of the received power patterns (i.e., RSSI), without being affected by multipath propagation typical of indoor environments.

If fact, the adopted signals of large bandwidth (i.e., very narrow pulses) travel between the transmitter and the receiver with a myriad of different paths due to the reflections of objects and of the building. However, the receiver is able to distinguish among them, and compute the TOA of the first path only, carrying the reliable information about the travelling time.

Due to the very large bandwidth adopted, an extremely low transmitting power is used. The severe limits imposed by regulation ensure that no interference is created to other radio communications. The main drawback is the limited range among the devices (tens of meters).

Our UWB solution is certified for the CE market according to the harmonized standard ETSI EN 302 065-2.

Both LT1 and LT2 configurations are implemented (corresponding to UWB channel 2 and channel 5 of the IEEE 802.15.4a standard).

Key benefits of the UWB technology:
  • High accuracy
  • Immunity to multipath fading (i.e., reliable indoor positioning)
  • No interference to other radio services
  • Very low power

Decawave Partner