Emerging Trends of Space-Based Wireless Sensor Network and Its Applications

Why Swsn?

In the year 1960, the first satellite TIROS-1(a US meteorological satellite) was launched for earth observation. Currently there are 1100 active satellites (including government and private launchers) and 2600 satellites that are non-functional. Figure 1 shows illuminated small light as the satellites in the orbit. The federal communications commission in space found that non functional satellites weighing up to 6 tons and size of a small school bus. These non-functional satellites can cause collision with the active satellites. These are called as space debris. However rules says to burn the unused satellites within 25 year either by dropping them back to earth for Low Earth Orbit (LEO) satellites or lift them up, such that they don’t collide with the active satellite in orbit in case of Geostationary Earth Orbit (GEO) satellites (Cornara, Beech, Belló-Mora, & Martinez de Aragon, 1999). The design and implementation of successful satellite network is a complex and iterative process involving a huge cost. The above mentioned statistics brings a great demand for efficient satellite network in space. The current space environment demands for faster, better and cheaper satellites with high performance and reliability.

The growing demand in various satellite based applications is the motivation for launching large number of satellites in space. Large satellites weigh more than 100 kilograms (kg). These satellite missions would generally be a billion dollar programs and any small fault would lead to the entire mission failure causing huge loss and also increases the space debris. This has motivated the current researches to have a paradigm shift from single large satellite to large number of small satellites. These small satellites collaboratively work to achieve the objective of large satellite mission KISS (keep it small and simple).

Figure 1.

Non functional satellite forming debris in space