In your smartphone you have a miniature GPS receiver, which has a long story behind it. When the first tracking system became operational in 1995, it was as big as a tablet. Today, we have it integrated into our mobile phones in the form of an integrated circuit. The size of a Global Navigation Satellite System (GNSS) chip is getting smaller with every new launch. It has gone down to 25 mm².
Reduction in chip size has enabled its use with other handheld devices. This article takes a look at some interesting technologies and improvements driving modern GNSS chips, modules and other solutions.
Navigation is a necessity, with uses ranging from a simple human guidance system to a missile tracking system. Majority of such systems involve one or the other kind of GNSS system. GPS, the first guidance system, was set up with the idea of guiding various military operations. But this century has seen the emergence of several other guidance systems, which also together with GPS have helped improve geo-location.
An era of change
As technology improved over the years, performance of GNSS systems has also improved steadily through availability of multiple constellations of satellites to sync with. Several constellations have gone live and are giving GPS a run for its money. According to Sudhir N.S., senior manager – GNSS technology, Accord Software, “From the usage point of view, people are still slow in taking up multi-constellation systems. GPS is still hogging most of the number of chips sold, but other systems are catching up.”
Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) from Russia, BieDeu from China, GPS Aided GEO Augmented Navigation (GAGAN) from India and Galileo from Europe are some such systems that have improved the tracking. At any given moment we have about 84 operational satellites, solely for the purpose of navigation.
According to Ashish Gulati, country manger, Telit Wireless Solutions, “This means that we are not dependent on the US GPS constellation, and now have the option to go ahead and work with GLONASS, Galileo and others.”
Sudhir says in agreement, “I feel multi-constellations will help in cases where open-sky visibility is not possible. If we were to take vehicle tracking as an example, consider a case of a vehicle tracking unit inside a vehicle. Here, the antenna would have to be embedded since customers today prefer self-containing units with internal antennae and sufficient battery backup to prevent tampering.”
Why multiple constellations is a good thing?
Hidden navigation systems might receive deteriorated signals from satellites, so having multiple constellations will double the number of satellites and better the chances of a good-quality signal being available to users. It could be for anyone, from common people like us to the military stuck in tough terrain.
Rakesh C.R., field application engineer – GNSS Microelectronics and Solutions, Accord Software, states, “In defence application, which is more strategic in nature, people want multi-constellation availability, so that if one service is denied for any reason, they can fall back on other systems. IRNSS is almost available, too. Reliance on IRNSS is going to be much higher in India.”