UWB Antenna Positioning Principle

　　Ultra – Wideband (UWB) antenna positioning is a high – precision wireless
positioning technology that operates based on the transmission and reception of
short – duration electromagnetic pulses. Unlike traditional narrow – band
wireless technologies, UWB utilizes a wide frequency band, typically ranging
from 3.1 GHz to 10.6 GHz, to transmit signals, enabling extremely accurate
ranging and positioning capabilities.

　　The core principle of UWB antenna positioning relies on measuring the time
– of – flight (ToF) of the UWB signals between multiple antennas. When a UWB –
enabled device, such as a tag or a sensor, sends out UWB pulses, these pulses
are received by multiple UWB base stations or anchors. By precisely measuring
the time it takes for the signal to travel from the tag to each anchor, the
distance between the tag and each anchor can be calculated using the formula:
distance = speed of light × time – of – flight. Since the speed of light is a
known constant, accurate time measurement is crucial for obtaining precise
distance values.

　　To achieve high – precision time measurement, UWB systems employ techniques
such as two – way ranging and multi – path mitigation. In two – way ranging, the
tag and the anchor exchange UWB signals in both directions. By measuring the
round – trip time of the signals and compensating for the processing delays at
both ends, a more accurate one – way time – of – flight can be determined. Multi
– path mitigation is also essential as UWB signals can bounce off objects in the
environment, leading to multiple signal paths reaching the receiver. UWB
antennas and signal processing algorithms are designed to distinguish the direct
path signal from the reflected signals, ensuring that only the direct path time
– of – flight is used for distance calculation.

　　Once the distances between the tag and multiple anchors are obtained, the
position of the tag can be calculated using geometric algorithms. The most
common method is trilateration, where the position of the tag is determined as
the intersection point of three or more spheres centered at the anchors with
radii equal to the measured distances. In a two – dimensional scenario, the
principle is similar, using circles instead of spheres. Another approach is
multilateration, which can use more than three anchors to improve the accuracy
and robustness of the positioning system. By continuously measuring the
distances and calculating the position, UWB antenna positioning can provide real
– time, high – precision location information, with accuracies often reaching
within a few centimeters.