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GNSS inside


Detecting secret nuke tests from space
If you thought the best use of GPS was to simplify your hunt for the nearest Pizza Hut outlet or to help you find the smoothest way to office during peak rush hour, then its time you tweaked the grey matter a little more. With technology advancing at a brisk pace, new uses of GPS are being discovered every day.

Recently, the Comprehensive Nuclear-Test-Ban Treaty Organisation (CTBTO), which seeks to enforce the Comprehensive Nuclear-Test-Ban Treaty, got a shot in the arm with the amazing new revelation that the Earth’s Global Positioning System could be used to track clandestine nuclear tests.

The latest finding came to the fore when scientists examined GPS data from 25th May 2009, the same day when North Korea had conducted its much criticised nuclear test. The data suggested certain unusual changes in the electron density of the upper atmospheric layer of the Earth known as the ionosphere. The data collected from regions across North Korea showed a bubble of disturbed particles from the test site spread out into the atmosphere.

Although authorities already have several techniques to discover secret nuclear tests such as seismic detectors that pick up shockwaves through land and acoustic sensors for identifying shockwaves through water, it was extremely difficult to detect nuclear explosions that happen deep beneath the ground.

GPS can effectively complement other techniques of sensing nuclear tests to help confirm when an explosion occurs, especially several feet below the Earth’s surface.

Specially designed computer algorithms hunt for GPS signals for certain strange patterns representing an unexpected variation in the electron density at some specific locations in the Earth’s atmosphere, which is exactly what happens when a shockwave from a nuclear explosion shoves an air bubble through the atmosphere. Further, the timing of the shockwave calculated with respect to its speed and the time it takes to travel to different stations helps scientists zero in on the exact location of the nuclear explosion.

While GPS was initially conceptualised as a system for location purposes, it has always been extremely sensitive to even the slightest of atmospheric disturbances, a property that helps it in discovering secretive nuclear tests.

The latest finding could have certain extremely valuable implications for the UN’s nuclear watchdog IAEA (International Atomic Energy Agency) as it looks to contain illegal nuclear tests that pose a grave threat to the very existence of mankind.

Unlocking the mystery of earthquakes
Earthquakes that shake the ground beneath our feet like tender grass in the wind and cause colossal damage and destruction to life and property have always been one of the deadliest natural disasters. But, even after years of tireless efforts and billions of dollars worth of research, scientists have found themselves hapless when it comes to predicting earthquakes and saving millions of lives.


However, a new path-breaking finding has given a ray of hope to scientists in their fight against earthquakes. An expanded network of GPS (Global Positioning System) sensors that envelopes the Pacific Northwest region in North America can track even the slightest movement beneath the surface of the earth and thus help in predicting an impending disaster. The web of GPS devices can detect even miniscule movements of tectonic plates and beam data back in a flash to give scientists an indication of the hidden activity in as little as five seconds.

Known as PANGA or the Pacific Northwest Geodetic Array, the system is still in its initial stages of development and once fully operational it will be able to locate earthquakes with several times the accuracy of traditional seismometers. With further research and development, the PANGA would be able to issue warnings for disastrous quakes and destructive Tsunamis well in advance.

The system helps scientists collect and use the GPS data to measure the gradual increase in strain on the tectonic plates and thus identify the vulnerable areas that are most likely to buckle under the mounting pressure. While until a few years ago, there were just about 20 instruments positioned in and around the Northwest Pacific region that sent across data once in 24 hours, the rapid advancement in technology as well as the affordability of these instruments has meant that there is a maze of around 450 such instruments engulfing the region today that shoot out precious data every second. When operating in top mode, PANGA’s sensors can sense movements as minute as one-tenth of a millimetre.

GPS has revolutionised the study of geology by offering us an insight of the tectonic forces that shape the earth’s landscape and give rise to earthquakes and volcanoes.

Although traditional seismometers can measure the intensity of an earthquake with great accuracy, it is possible for them to be overwhelmed by huge quakes such as the one that hit Japan a few months back. Seismometers recording the Japan quake had termed it as a jolt of intensity 8 on the Richter scale while scientists later found it to be a magnitude 9 quake. The Tsunami that followed the massive shock also proved to be of much higher intensity to what was initially predicted because of the wrong assessment.

Lifesaving tech: Making flying safer
On a chilly winter evening in 1996, the people of Charkhi Dadri village near India’s capital city, New Delhi, were woken up from their slumber by a deafening noise. Eyewitnesses saw a big ball of fire in the sky followed by pieces of molten metal and burnt human flesh crash down in the nearby fields.

As the dust settled, details of one of the worst ever mid-air airplane collisions in the history of mankind started to emerge. The crash between Saudi Arabian Airlines Flight 763 and Kazakhstan Airlines Flight 1907 had resulted in the death of all 349 people on board and left plenty of others emotionally scarred for life.

Despite tremendous advancements in technology over the past few decades, mid-air collisions have continued at a steady rate. What probably makes these tragedies worse is the fact that the possibility of finding survivors in a mid-air crash is almost nil as compared to accidents involving other means of transport.


Scientists at the Massachusetts Institute of Technology have now come up with an innovative algorithm that could significantly reduce the possibility of a mid-air plane crash and thus help to make the skies safer.

The advanced technology developed by the MIT International Centre for Air Transportation makes use of Global Positioning System (GPS) data to create hypothetical puck shaped spaces around planes to help them keep at a safe distance apart from each other. The size of the imaginary puck shape depends on the direction and speed at which the two planes on collision course are travelling.

The system was developed after months of vigorous research by a group of scientists, who made use of real world flight-data to model the innovative technology.

One of the major challenges facing the researchers was to minimise the chances of a false alarm. To achieve that, it was decided to use two degrees of alarm; a moderate one to signal that the paths of the planes were converging, while another severe alert to suggest that a collision is imminent.

While the product is still in its final stages of development, scientists are planning to use it on real planes soon to see if it actually works.

If successful, the system will help avert some of the worst air tragedies and save plenty of innocent lives.

A drive into the future!
How often have you cursed your mobile GPS (Global Positioning System) device for being inaccurate and hard to understand? Remember those days when you would find yourself struggling with the GPS device in your car simply because the map looked completely different from the place you were driving in or you forgot to install the latest update and as a result your device did not recognise the newly built road?

With technology becoming handier and more advanced with every passing minute, life has become simpler and it is now as easy to navigate your way through a completely unknown place as it is to wake up in the morning and walk to your bathroom. The latest innovative application to hit the market that will completely change the way you navigate is the Wikitude Drive.


The application, unlike conventional GPS devices that display a line on a 2D map to help you track your path, uses the mobile phone’s camera to capture the live view of the road you are driving on and overlays the map on top of that to give you an absolutely real feel.

The most significant use of the application is that, in effect, you never have to take your eyes off the road and that minimises the chances of a mishap. Apart from that, the application consists of all other traditional features that most navigation devices have such as trip planning, night driving, turn-by-turn navigation as well as voice command. Another advantage of the application is that it upgrades itself automatically and remains there to help you even when you are outside your car. So, it can help you steer your way through a labyrinth of unfamiliar alleys even in a completely unknown city. Once fully operational, the Wikitude Drive will mean an end to all those nagging issues of the traditional navigation apps and offer an all new dimension to how we travel.

Be ready for a drive into the future!

Noise knows your whereabouts

We tend to ignore usual noise emitting from vents, computers, lights and appliances without realising that these noises can actually help track individuals if we tag them with acoustic fingerprints. Although the unrealistic idea seems straight out of a fairytale, the innovative practice of figuring out one’s location using sound has been turned into a possibility by a new mobile phone application called Batphone.

Global Positioning System (GPS) can pinpoint a mobile phone user’s location with absolute precision while the person is outside; however, that is not the case when the user is indoors. That is where Batphone comes into play by letting your phone listen!

The inventive application uses your phone’s microphone to record usual noises emitting inside a room and tag it with a unique acoustic fingerprint. This information can be used by future users to recognise previously- tagged rooms and thus identify their location. For comparison, it also shows the position retrieved from location services, which determines users’ coordinates using GPS, Wi-Fi and cellular base stations.

While global navigation satellite system (GNSS) – powered devices are the most popular tracking tool so far, its limitation when it comes to indoor tracking has proved to be a big barrier. To overcome this limitation GPS evolved into ‘Assisted GPS’ which used the cell phone’s GPS chip and cellular network. In the absence of Assisted GPS, operators used Wi-Fi geolocation technology but precision of accuracy always remained a huge concern for indoor tracking service providers.

While Batphone undoubtedly looks to be an application full of promise, it is still in its developing stages and has a long way to go before it can become the future of location based tracking.

A tech-driven parking solution
Rapid urbanisation, industrialisation and population growth has led to an exponential increase in the number of automobiles, which has resulted in massive parking problems, especially in the metropolitan areas. According to some estimates, drivers looking for parking space waste about 95,000 hours every year and burn 47,000 gallons of gasoline. The amount of carbon dioxide produced in this entire exercise is equally staggering at around 730 tonnes.


In an attempt to address this issue, researchers at Rutgers University’s Wireless Information Network Laboratory in New Jersey studied real-time traffic monitoring using ultrasonic sensors, GPS location finders and wireless networks to develop an innovative application. Known as ParkNet, the mobile system comprises of vehicles that collect parking space occupancy information as they drive by.

The basic plan behind the working of ParkNet is to equip vehicles such as taxis, municipal vehicles and security cars that travel frequently in an area with sensors that are capable of measuring distances to obstacles and thus determine whether there is an available parking space.

The GPS receiver attached to the ParkNet aggregates all the available data at a central server, which in turn builds a real-time map of parking availability and provides this information to clients who query the system in search of a parking space.

However, creating an accurate map of parking availability was a challenge for researchers due to GPS location accuracy limits. To address this issue, an environmental fingerprinting approach was devised, which resulted in accuracy limits shooting up to almost 90 percent.

Although the inventive application is still in its developing stages, once fully operational in about two years time, ParkNet will prove to be of immense help for drivers who wake up every morning with the stress of having to drive down to their offices and trying to fight it out for the limited parking space available.