Move over conventional satellite navigation; a new hero is in town. Distance measurement is on the cusp of a revolutionary tech, and it’s a doozy.
It has been forever since distance measurement methods have changed for satellite navigation. Navigation and maps have become a quintessential part of our lives and are the all-powerful tools for every trekker, hiker, and strange tourist out there. But navigation isn’t used just for travelling. The navigation and distance measurement systems form a considerable chunk of geographical studies and research on land and almost everywhere.
The Current System
Everyone has heard of the term ‘GPS’. Global Positioning System is a satellite-based distance measurement and navigation system that works on the principle of triangulation. There are a total of 24 satellites spread across the outer atmosphere of Earth. The triangulation method involves utilising three satellites at the same time to geo-locate a GPS signal.
When the user activates their GPS, the signal is sent to the satellites. The sign is triangulated using the three nearest satellites, and an accurate position can be deduced. Similarly, GPS navigation works based on triangulating both the start and end of the route and using a system’s existing database to suggest the best possible travel route. While this system is easy to understand and to use, it does have its limitations.
For starters, GPS isn’t 100% accurate, and the exact location can be offset in the range of 3-15m even with the best possible measurement. Secondly, there is a noticeable time delay between each signal relay. Although light is the fastest traveling entity in the universe at 300,00 km/h, it still shows a tiny delay when communicating with a satellite 24,000km above the Earth’s surface. While the time difference may not feel much, it significantly affects the precision and calculating the efficiency of GPS navigation.
It’s Time for Quantum Mechanics!
So, where does this new system fit? The laser detection method is conventionally used to pinpoint the location of objects such as buildings, monuments, mountains, etc., as well as routes to these places. These laser beams are shot in pulses, and the time difference between sending and receiving the signal determines the distance between the 2 points. But this system also exists in GPS. So, what’s the catch?
The main difference in the new system, called Quantum-Limited Precision (QLP), reduces noise in the measurement system. Noise is a term familiar to everyone who has clicked at least one photograph in the night light. Not desirable, right? Imagine the same scope of noise levels while relaying the laser pulses. The noise occurs when two pulses start to overlap. This overlapping causes the vibrations to lose some of their light intensity, resulting in weak, inaccurate data/results. This is formally called the resolution limit and is a widespread occurrence in photos.
With QLP, the overlapping pulses are compared to its copy-pulse with a method called optical autocorrelation. This method works by interfering with a femtosecond pulse with a time-delayed copy within a nonlinear crystal. Then, the resulting intensity is recorded as a function of the time delay and frequency. Since these measurements are done on femtosecond (10-15 s) timescales, precision is of utmost priority. Navigation Systems have largely remained unchanged for decades.
A Big Upgrade?
The most significant difference will be noticeable in terms of LIDAR operations. LIDAR requires exact science, and the improved levels of accuracy will surely help. Due to the resolution limit of existing systems, GPS cannot resolve small structures and textures. QLP aims to solve that issue. Collaborating with the Czech Republic and Spain, Paderborn physicists have successfully quantified these values when the pulses overlapped by 90 per cent.
The new and improved LIDAR system will help detect potential threats to landmasses, like the A68a iceberg, and monitor faults in tectonic plates and phase shifts. The course will also trickle down to the consumer stage in the form of an improved GPS. Physicists have mentioned combining QLP with Quantum Information Theory to devise better and simpler technological systems that can be used widely and effectively.
The tech is still at a breakthrough stage, and only further development will reveal its true potential.