Free Newsletters - Space News - Defense Alert - Environment Report - Energy Monitor
. 24/7 Space News .




GPS NEWS
Galileo's search and rescue system passes first space test
by Staff Writers
Paris (ESA) Jan 30, 2013


Spectrum of the L-band signal received from the third Galileo satellite's Cospas-Sarsat search and rescue repeater at ESA's Redu Centre on 18 January 2013. This first switch-on represents the intial step in the expansion of the Cospas-Sarsat system into medium-Earth orbit.

The first switch-on of a Galileo search and rescue package shows it to be working well. Its activation begins a major expansion of the space-based Cospas-Sarsat network, which brings help to air and sea vessels in distress. The second pair of Europe's Galileo navigation satellites - launched together on 12 October last year - are the first of the constellation to host SAR search and rescue repeaters.

These can pick up UHF signals from emergency beacons aboard ships and aircraft or carried by individuals, then pass them on to local authorities for rescue. Once the satellites reached their 23 222 km-altitude orbits, a rigorous test campaign began. The turn of the SAR repeater aboard the third Galileo satellite came on 17 January.

"At this stage, our main objective is to check the repeater has not been damaged by launch," explains ESA's Galileo SAR engineer Igor Stojkovic.

"The first day was a matter of turning the repeater on and checking its temperature and power profiles were as predicted.

"The following day involved sending a signal to the repeater using the UHF antenna at ESA's Redu Centre in Belgium, then picking up the reply from our L-band antenna."

Redu's antenna is 20 m in diameter, so the shape of the relayed signal was captured in great detail, out of all proportion to surrounding noise.

"We can precisely measure its power, the time the relay took and so on," adds Igor.

More detailed system testing will follow, to completely prove this new type of SAR payload in orbit.

This international system has been taking the search out of search and rescue for more than three decades, saving some 31 000 lives along the way.

Cospas is a Russian acronym for 'Space System for the Search of Vessels in Distress', with Sarsat standing for 'Search and Rescue Satellite-Aided Tracking'.

Ground stations - known as Local User Terminals - pinpoint the source of distress calls using signals relayed by participating satellites, then alert local authorities.

Founded by Canada, France, Russia and the US, Cospas-Sarsat now has 43 participating countries and organisations. It began with payloads on low-orbiting satellites, whose rapid orbital motion allowed Doppler ranging of distress signals, to pinpoint their source. Their drawback is their field of view is comparatively small.

The system added payloads on geostationary satellites, which continuously see a third of the globe, but because they do not move relative to the ground they cannot locate signals directly.

The SAR repeaters on these two Galileo satellites are the first of a new class of 'MEOSAR' repeaters, combining broad field of views with the ability to quickly determine positions.

Galileo's satellites are also the first with the capability to despatch return link messages via their navigation signals, assuring those in distress that help is on the way.

An additional advantage of this new MEOSAR system is that less ground infrastructure is required - just three to four terminals are sufficient to serve all European territory.

This initial SAR unit's transponder was built by Mier Comunicaciones in Spain, with its combined receiving and transmitting antenna developed by Spain's Rymsa company.

The SAR payload of the fourth Galileo satellite is due to be switched on for testing in the coming weeks.

More detailed end-to-end testing of the repeaters will follow in the spring, using a dedicated system called the Galileo Search and Rescue Validation Test Bench based at France's Cospas-Sarsat control centre in Toulouse.

The unit can simulate multiple beacon messages for the system to find their location and relay them accordingly.

Further SAR payloads will follow these first two into orbit with the launches of follow-on Galileo Final Operational Capability satellites.

.


Related Links
Cospas-Sarsat at ESA
GPS Applications, Technology and Suppliers






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





GPS NEWS
AFRL Selects Surrey Satellite US to Evaluate Small Satellite Approach to GPS
Englewood, CO (SPX) Jan 22, 2013
The Air Force Research Laboratory (AFRL) has selected Surrey Satellite Technology US LLC (SST-US) to investigate cost reduction and augmentation of the current GPS constellation through the application of the small satellite approach. AFRL has contracted SST-US to identify and analyze how small satellites can improve aspects of GPS system performance such as accuracy, coverage, and robustn ... read more


GPS NEWS
US, Europe team up for moon fly-by

Russia to Launch Lunar Mission in 2015

US, Europe team up for moon fly-by

Mission would drag asteroid to the moon

GPS NEWS
Changes on Mars Caused by Seasonal Thawing of CO2

Is there life on Mars?

Opportunity At Work At Whitewater Lake

Thawing Dry Ice Drives Groovy Action On Mars

GPS NEWS
Companies prepare commercial spacecraft

NASA to recycle parts for science work

TDRS-K Offers Upgrade to Vital Communications Net

How to predict the future of technology

GPS NEWS
Reshuffle for Tiangong

China to launch 20 spacecrafts in 2013

Mr Xi in Space

China plans manned space launch in 2013: state media

GPS NEWS
NASA to Send Inflatable Pod to International Space Station

ISS to get inflatable module

ESA workhorse to power NASA's Orion spacecraft

Competition Hopes To Fine Tune ISS Solar Array Shadowing

GPS NEWS
Russia Set for Year's First Baikonur Space Launch Feb. 5

First Ariane 5 For 2013 Ready For Loading

Azerspace And Africasat-1a "fit" for Ariane 5 launch

NASA Selects Experimental Commercial Suborbital Flight Payloads

GPS NEWS
The Origin And Maintenance Of A Retrograde Exoplanet

New Evidence Indicates Auroras Occur Outside Our Solar System

Glitch has space telescope shut down

Earth-size planets common in galaxy

GPS NEWS
Laser-Plasma Process Gives Nanohybrid Remarkable Properties

DNA and quantum dots: All that glitters is not gold

Liquid metal makes silicon crystals at record low temperatures

Supercomputer sets computing record




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement