- Buyers Guide
David Vye, MWJ Editor
Reach for the Stars
Last night my family and I watched the updated version of Carl Sagan’s television series “Cosmos” with new host Neil Tyson. Coupled with the national excitement over the Apollo moon missions, the original show was an amazing television experience that encouraged a generation of young people in the 1960’s and 70’s to pursue careers in science and related fields. The revised version leverages today’s superior computer graphics and greater understanding of the universe to make this series a truly entertaining and inspiring event. I recommend that engineers watch it to recharge their enthusiasm for knowledge and discovery and parents watch it with their families to spark their own children’s interest.
One of the best known figures in the history of modern astronomy is Italian physicist Galileo. This week, the European Space Agency (ESA) announced that a satellite navigation constellation sharing his name achieved in-orbit validation. Europe now has the operational nucleus of the world’s first civil-owned and operated satnav system.
In 2011 and 2012 the first four satellites were launched into orbit. In the following year, these satellites were combined with a growing global ground infrastructure to allow the project to undergo its crucial In-Orbit Validation phase (IOV). Guests of last year’s EDI CON event in Beijing China heard from keynote speaker, Bertram R. Arbesser-Rastburg, Head of the Electromagnetics and Space Environment Division of the ESA talk about Galileo and give examples of advanced microwave technology being used in Earth observation, telecommunications and navigation.
At EDI CON 2013, Arbesser-Rastburg discussed how microwave instruments are used for active remote sensing (like synthetic aperture radars, cloud radars and altimeters) and for passive observations (radiometers and profilers extending up to hundreds of GHz) and the challenge in telecommunications to maximize the capacity of the existing frequency allocations, requiring multi-beam antennas operating at high power levels.
Galileo’s observed dual-frequency positioning accuracy is an average 8 m horizontal and 9 m vertical, 95% of the time. Its average timing accuracy is 10 billionths of a second – and its performance is set to sharpen as more satellites are launched and ground stations come on line. For Galileo’s search and rescue function – operating as part of the existing international Cospas–Sarsat programme – 77% simulated distress locations can be pinpointed within 2 km, and 95% within 5 km. All alerts are detected and forwarded to the Mission Control Centre within a minute and a half, compared to a design requirement of 10 minutes.
This year’s EDI CON will offer several sessions devoted to satellite navigation and communication systems, perhaps inspiring a new generation of Chinese microwave engineers in the possibilities of space or at least allowing the global microwave community to share insights into one of our most inspiring applications. Back in the states, the Satellite 2014 show took place in Washington DC this week (see MWJ Technical Editor, Pat Hindle’s show wrap-up online). This annual event is a great opportunity for microwave component manufacturers and design engineers to experience an eco-system that puts our technology to good use in the service of scientific discovery.