Ultra Wide Band (UWB) is a technology for the transmission of data using techniques which cause a spreading of the radio energy over a very wide frequency band, with a very low power spectral density, which limits the interference potential with conventional radio systems.  UWB is most commonly used for tracking location of items with high accuracy.

The Andibee system transmits UWB impulse radio signals with an accurate time stamp.  These are received by other nodes and returned to the original sender.  The sender now knows the total travel time of the signal and can calculate the distance between the nodes based on the speed of light in air.  This method is called single-sided two-way ranging (as only one side knows the distance).  Different algorithms can be used with this timing data to improve the accuracy of the measurement.  For example, double-sided two-way ranging give a standard deviation in the distance measurement of 4.5cm.  This is regardless of the distance between the nodes.

By spreading the transmission power over a broad spectrum, UWB communications are both highly jamming resistant and difficult to detect, both highly prized attributes in a military context.  UWB transmits a finely tuned pulse that equates in the frequency domain to a 500MHz bandwidth signal with a centre frequency that can be set to a range of values.  There is no carrier wave and so the system would only be detectable when broadcasting and, typically, a single broadcast only lasts 1ms.  The standard power output of the UWB system is -41.3dBm/MHz/ms and as this is spread over 500MHz, the power in any single frequency is very low.

Typically, UWB is used in fixed location with a considerable amount if infrastructure required (anchor nodes spread around a building with data and power connections) and over a relatively short distance.  This is for tracking items such as pallets in a warehouse.  At Andibee, we've been working on extending the functionality of UWB systems to reduce the infrastructure requirements (down to one or two nodes) and increasing the range (successful tests up to 1.6km).  This broadens the application and can be used for location of autonomous vehicle swarms such as drones or rovers.