Space blog - Galileo and GPS

Green light for Galileo satellites

nospam@example.com (Robin Wolstenholme) — Thu, 07 Jan 2010 13:05:17 +0000

Today at 12:30 in Brussels, the EC announced that the SSTL and OHB-System team has been selected by ESA to supply 14 navigation satellites for the deployment phase of the Galileo satellite navigation system in a deal worth 560m Euro.

Galileo satellite

The two companies agreed to work together as a “core team” on Galileo at the end of 2007, with OHB taking the role of prime contractor and builder of the spacecraft “bus” and SSTL taking full responsibility for the navigation payloads onboard the satellite that will form the heart of the Galileo navigation system.

SSTL Group CEO Dr Matt Perkins is delighted with the news:

The award of this contract is an important step for SSTL. Our satellites are already providing operational services for many government and commercial customers and we are pleased to have a major role within Europe’s flagship Galileo programme. The experience gained on GIOVE-A will help us to ensure the contract will be a success for the EC and ESA. This programme will also help to establish SSTL as a provider of communications and navigation satellites into other markets.

It was champagne all round at SSTL in Guildford as the news was announced, warming spirits despite worst snow for 30 years affecting the local area.

A jubilant SSTL’s Executive Chairman, Sir Martin Sweeting, added

This award is great news for the UK space industry and once again confirms SSTL as a world leader in sophisticated satellites and payloads, building on its 25-year history pioneering small satellites with 34 already launched, truly changing the economics of space.

The first Galileo satellites produced under this contract will be launched from 2013. To help improve the overall schedule the team was authorised by the EC and ESA to initiate the procurement of long lead items for the full system during 2009 which will enable the team to make a quick start towards an operational Galileo constellation.
Continue reading "Green light for Galileo satellites"

Galileo satellite's 4th birthday today

nospam@example.com (Robin Wolstenholme) — Mon, 28 Dec 2009 07:54:52 +0000

SSTL is celebrating the 4th anniversary of the launch of its historic GIOVE-A satellite today. As the first of the Galileo In Orbit Validation Element satellites, GIOVE-A was the first step in Europe's visionary Galileo satellite navigation programme when it was launched on December 28th 2005.

During the past 4 years, SSTL and GIOVE-A have contributed significantly to the testing and validation of technologies vital to the now imminent operational constellation of satellites. The 660 kg GIOVE-A satellite was built by SSTL for ESA in just 30 months at a cost of just 28m Euros.

SSTL CEO Dr. Matt Perkins commented

SSTL is proud of its involvement with the Galileo programme and the continuing success of GIOVE-A. This mission has clearly demonstrated the effectiveness of SSTL’s small satellite approach for the delivery of operational missions.

GIOVE-A was the first part of the in-orbit validation programme for Galileo, broadcasting the first signal to successfully secure the critical Galileo frequency filing with the International Telecommunications Union (ITU) at 17:25 GMT on the 12th January 2006. This was a significant achievement for SSTL having commissioned the necessary systems to achieve this broadcast in just 3 weeks.

On the 2nd May 2007 GIOVE-A successfully transmitted the first Galileo navigation message from space, containing the information needed by users' receivers to calculate their position using the future Galileo satellite navigation service. These signals have since been used for signal quality testing and for equipment manufacturers and the scientific community to validate prototype Galileo receivers.

Throughout the past 4 years, the satellite has provided valuable data about the Medium Earth Orbit which the Galileo constellation will occupy, helping to characterise the radiation environment and validating subsystems such as an atomic clock and the Galileo signal broadcasting payload.

In July and August this year, GIOVE-A was gradually moved to a higher orbit to ensure that it does not cross the operational Galileo constellation’s orbits when the first operation satellites are launched in 2012. The satellite has been in orbit for 21 months beyond its original 27 month mission design life and continues to provide critical data to all of the ground users experimenting with Galileo navigation signals

SSTL, together with its partner OHB-System of Bremen, Germany form the core team of one of the two consortia bidding for the operational satellites. The final proposal was delivered to ESA in November and the outcome of the evaluation process is awaited. To help improve the overall schedule the team was authorised by the EC and ESA to initiate the procurement of long lead items for the full system earlier this year. The British space pioneer looks forward to continued success supporting the European Space Agency (ESA) and the EC with the expertise it has gained and its cost effective and reliable approach to satellite and subsystem design and manufacture.

GALILEO and GMES headline EU space conference

nospam@example.com (Robin Wolstenholme) — Fri, 18 Sep 2009 11:42:18 +0000

On October 15th and 16th, the great and the good will descend on Brussels to discuss the future of the European Space Policy. The conference, which is named “The ambitions of Europe in Space” will address Europe’s most ambitious programmes: GALILEO and GMES and their prospective benefits to technology, industry and society.

Prominent guests will include President of the European Commission, José Manuel Barroso, the President of the new European Parliament, Jerzy Buzek, and the President of the European Investment Bank (EIB), Philippe Maystadt. Several others European leaders, such as Vice-Presidents Antonio Tajani and Jacques Barrot, or Jean-Jacques Dordain, General Manager of ESA also confirmed their participation.

Conference organiser Business Bridge Europe (BBE) will bring together European Institutions, national and local public authorities, R&D centres, manufacturers and everyone interested in meeting and discussing space policy, space systems’ applications and their financing.

On the 15th SSTL CEO, Dr. Matt Perkins will deliver a keynote speech about “The external dimension of the space authority: the example of Africa” alongside other industry representatives. The following day, DMCii Managing Director, Dave Hodgson will join other remote sensing experts from ESA and industry to discuss “Environment, Energy, Home Land Security and Agriculture”.
Continue reading "GALILEO and GMES headline EU space conference"

Galileo satellite progress from Paris

nospam@example.com (Robin Wolstenholme) — Thu, 18 Jun 2009 10:47:23 +0000

Gaileo is turning out to be a hot topic at this year's Paris Air Show. On the 15th June ESA and Arianespace signed a contract for the launch of the first four operational Galileo satellites on two Soyuz launch vehicles from Europe’s Spaceport in French Guiana. Also this week, ESA and the OHB/SSTL consortium signed a contract for sourcing long-lead items for Galileo satellites.

The Galileo In-Orbit Validation (IOV) Launch Services Contract covers the launch of the first four operational Galileo satellites using two Soyuz launch vehicles that will lift off from the Guiana Space Centre (Centre Spatial Guyanais – CSG), Europe’s Spaceport in French Guiana.

Galileo IOV launch signing
ESA - S. Corvaja, 2009

This new development follows the successful launch of the GIOVE-A satellite which was built by SSTL and the GIOVE-B satellite which was to be built by the European Satellite Navigation Industries satellite consortium and ultimately completed by Astrium. Both satellites have provided a great deal of data, for example helping with with clock characterisation, Galileo signal testing and in understanding the radiation that future Galileo satellites such as the new IOV satellites can expect in Medium Earth orbit (MEO).

The signature of the IOV Launch Services Contract in Paris marks an important milestone for the Galileo programme as it progresses towards the operational deployment of the satellites of the Galileo satellite navigation system. The four IOV satellites will be placed in a circular orbit at an altitude of MEO of 23 600 km by the end of 2010. Development of the Galileo system is being carried out under a joint ESA/European Union programme.

The launch vehicle chosen to carry the four Galileo IOV satellites into orbit is the Soyuz ST-B with a Fregat MT upper stage, which has been adapted for the deployment needs of the Galileo programme. The Soyuz at CSG Programme is an ESA Programme with co-funding of Arianespace and the European Union.

Galileo operational constellation
Meanwhile, ESA and the bidder consortium led by OHB-System AG and Surrey Satellite Technology Ltd. (SSTL) have signed a contract for sourcing long-lead items for satellites for the future European Galileo navigation system in Paris the same week. The EUR 10 million contract is carried out under a program initiated and funded by the European Union.

Through this contract, OHB and SSTL are able to place orders for satellite technologies which require considerable lead times for development and sourcing ahead of the award of the actual contract for the construction of the satellites. The Galileo System customers, the European Union and the ESA, are thus ensuring that the schedule for implementation of Galileo can be maintained.

OHB and SSTL are one of two consortia bidding for the development and con-struction of 28 satellites for Galileo. By allowing two consortia to build spacecraft for this significant undertaking, ESA is ensuring that the full operational capa-bility can be put in place as soon as possible and at best value to the EU. The system is to be fully operational by 2013 following full contract signature later in 2009.

RIN GNSS conference in September

nospam@example.com (Robin Wolstenholme) — Tue, 24 Mar 2009 10:41:32 +0000

Many thanks to Dr. Renato Filjar for drawing our attention to the Royal Institute of Navigation and the Institute of Engineering Surveying and Space Geodesy, University of Nottingham 2nd GNSS Vulnerabilities and Solutions 2009 Conference to be held on 2 - 5 September 2009 in Baska, Krk Island, Croatia.

This four-day event aims to gather GNSS experts and focuses on GNSS problems and vulnerabilities, as well as to developments aiming to improve the accuracy and reliability of GNSS. Unique environment of Baska and its natural resources and rich history, combined with friendly hospitality will again create an inspiring atmosphere for ideas and knowledge exchange, well known to those who attended the last year's conference.

Two special sessions will be organised in order to address particular causes of GNSS vulnerabilities: Space Weather and Ionospheric Effects on GNSS, and Safety Critical Applications (including emergency situations management, homeland security and Intelligent Transport Systems). The rest of the conference will address other causes of GNSS vulnerabilities and means of their over-comings, such as GNSS system and augnetation vulnerabilities, GNSS interference and management, tropospheric impact on GNSS, navigation algorithms. The design of user equipment will also be considered, with an insight into user experience and applications.

Two special sessions will be organised to address particular causes of GNSS vulnerabilities: Space Weather and Ionospheric Effects on GNSS, and
Safety Critical Applications (concerning primarily ITS).

Extended abstracts should be submitted to Dr Renato Filjar, FRIN by e-mail no later than 1 May, 2009. His email address is rfiljar@vtsbj.hr

Dr. Renato Filjar invites you to join the leading GNSS experts and discuss the most important issues related to further exploitations of satellite navigation systems in the wonderful Mediterranean environment of Northern Adriatic. In addition, the organising committee kindly appreciate your efforts in informing your colleagues about the event.

For more details visit the RIN conference page

Galileo Open Service discussion at RIN

nospam@example.com (Robin Wolstenholme) — Thu, 08 Jan 2009 12:04:15 +0000

A one-day seminar discussing the Galileo Open Service is being organised by the Royal Institute of Navigation (RIN) Space Special Interest Group on the 12th February at the Royal Geographical Society, 1 Kensington Gore in London. Speakers from European organisations, Government, Industry and Users will make this an important event for anyone with an interest in Galileo, the European Global Navigation Satellite System.

If you want to find out more about the Galileo Open Service, whether "one size fits all" and discuss the market for the other Galileo services it's worth booking in.

SSTL's Phil Davies has been involved in Galileo since 2003, following the European global satellite navigation system's development from the outset of GIOVE and the launch to its first SSTL-built satellite GIOVE-A. His presentation is entitled "The cost benefit of simplifying Galileo".

Phil will be joined by fellow expert speakers representing satellite navigation equipment manufacturers and end users who will discuss the interoperability between Police, Fire and Ambulance and the impact of Galileo on Road Safety and separate talks on the closely related road pricing enforcement and inner city congestion charging.

The Galileo Open Service (OS) caters for mass-market applications. Similar to the free service currently provided to civilian GPS users, it provides signals for timing and positioning, without user authentication direct to any user with suitable equipment free of charge. For most purposes, cheap single-frequency receivers will be used, but increased accuracy is possible by utilising up to 3 signals. Galileo's Open Service applications will use a combination of Galileo and GPS signals to significantly improve performance in severe environments such as urban areas and offshore areas.

The Open Service does not offer integrity information, and the determination of the quality of the signals will be left entirely to the users. There will be no service guarantee or liability from the Galileo Operating Company on the Open Service.

For up to date infomrmation, speakers and to register please visit the RIN website.

US and EC reaffirm Galileo GPS commitment

nospam@example.com (Robin Wolstenholme) — Wed, 29 Oct 2008 16:01:57 +0000

The US and EC have reaffirmed their commitment to cooperate with regard to GPS and GALILEO interoperability.

Representatives of the United States and the European Community (EC) meeting October 23 in Washington, D.C., reaffirmed their commitment to the 2004 cooperation agreement on Galileo and GPS in the first plenary session convened under the agreement.

Inside GNSS

See press release The U.S. intends to continue to operate GPS

SSTL gets Galileo award

nospam@example.com (Robin Wolstenholme) — Mon, 20 Oct 2008 13:53:50 +0000

The Galileo team here at SSTL have been presented with an award by the European Space Agency (ESA) that acknowledges the successful GIOVE A mission and its outstanding contribution to the success of the Galileo programme. The award was presented by Didier Faivre of ESA’s Galileo Directorate to Elizabeth Rooney of SSTL at an event held at the European Space Technology Centre (ESTEC) in Noordwijk, The Netherlands, on 13th October 2008.

GIOVE-A award

SSTL was contracted into ESA’s Galileo programme in 2003, when it began building the first GIOVE test bed satellite as part of the Galileo In Orbit Validation Element (GIOVE) of Galileo. The satellite was rapidly built and launched before the end of 2005. Since then the company has been actively involved with the in-orbit testing of GIOVE-A and, more recently, GIOVE B, launched in April 2008.

Last month, SSTL together with its German partner OHB-System was downselected by ESA and the European Commission (EC) as one of two potential suppliers of satellites to the Galileo operational system to be deployed by 2013.

SSTL’s Commercial Director, John Paffett said:

The GIOVE programme clearly demonstrated the benefits of dual-source supply, SSTL's GIOVE-A was designed, built and tested in a rapid 28 month schedule which allowed Europe to claim the ITU frequency filing. Without GIOVE-A, ESA would have lost the rights to the entire Galileo system. Dual source supply is also important in ensuring that the operational Galileo system is available as soon as possible and at the lowest final cost to the taxpayer. The long term benefit of a competitive supply base for Galileo satellites should not be underestimated.

Paffett also believes that market forces will also give Galileo the required boost to develop satellite navigation equipment:

Galileo has a lot to offer the satellite navigation marketplace, whether it’s landing planes or simply providing reliable navigation in the mountains. The possibilities are endless but it won’t happen until the equipment manufacturers see a working constellation in space. The sooner this happens, the better.

Second Galileo satellite on track

nospam@example.com (Robin Wolstenholme) — Thu, 03 Jan 2008 11:00:19 +0000

SSTL’s second Galileo contract, GIOVE-A2, has progressed through a successful Critical Design Review (CDR). The small satellite is a follow-on mission to the successful GIOVE-A mission launched two years ago.

The two-day CDR meeting, attended by ESA representatives at SSTL’s headquarters in Guildford, reviewed the design changes between GIOVE-A and GIOVE-A2. The next stage in the project will progress towards manufacture.

ESA awarded the follow-on contract to SSTL in March 2007. The project covers initial activities leading to the construction of a further spacecraft for the Galileo satellite navigation system, based on SSTL’s proven GIOVE-A technology.

Galileo signal reflections monitor ocean weather

nospam@example.com (Robin Wolstenholme) — Wed, 28 Nov 2007 16:53:51 +0000

A pioneering experiment was launched onboard UK-DMC in 2003, that uses signals reflected from the GPS signals already in orbit to monitor the weather at sea. The joint team experiment team, comprising SSTL and the University of Surrey members has now succeeded for the first time in capturing a Galileo signal from SSTL's GIOVE-A satellite reflected off the ocean surface. Although the signal was weak, because the equipment is optimised for receiving GPS signals, this is an important achievement demonstrating the potential for determining the weather at sea with remote sensing satellites.

What's more, it seems this new development is well timed - the Partnership for Observation of the Global Oceans (POGO), a distinguished partnership of international scientists is calling for a stable network of satellites for surveying vast extents of the surface of the ocean to enable societal benefits' (see POGO release, BBC).

HRH Duke Of Kent is shown the Galileo results by Dr Martin Unwin and PhD student, Philip Jales

Coincidentally, HRH Duke Of Kent was visiting SSTL at the time and was given a whistlestop tour which touched on "bistatic radar" and "forward scatterometry" (keep reading...).

The pioneering GPS Reflectometry Experiment was launched onboard SSTL’s UK-DMC satellite in 2003 to demonstrate the use of GPS reflections to determine the roughness of the ocean, using a method called “bistatic radar” or “forward scatterometry”. This experiment has now successfully detected a Galileo satellite navigation signal reflected by the ocean’s surface. GIOVE-A, the first Galileo demonstration satellite, also built by SSTL, was commissioned by the European Space Agency and has been transmitting prototype Galileo signals since its launch in December 2005.

In early November, 20 seconds of data were captured in orbit above the Arafura Sea, north of Australia, and downloaded to Surrey for processing. Whilst the orbiting experiment on UK-DMC is not optimised for Galileo signals, enough of the reflected signal energy was received to allow the detection and plotting of the weak signal after processing by University of Surrey PhD student, Philip Jales. The shape of the reflection gives an indication of the sea roughness and hence the weather at that place and time, where the wind speed was around 14 mph (22 km/h).

SSTL's Global Navigation Satellite Systems (GNSS) / GPS head, Dr Martin Unwin (centre left) explained

“This is an important achievement in remote sensing and demonstrates the potential offered by Galileo for scientific purposes. A constellation of small satellites could be deployed at low cost to take measurements over the oceans where there are large gaps in forecast knowledge at present. An improved measurement system in space could be used to warn mariners of storms and to provide data for global climate change models - potentially even to detect Tsunamis.”

Dr Unwin is also enthusiastic about benefits of inter-system cooperation:

“Signals from Galileo, in conjunction with GPS and the Russian and Chinese systems, Glonass and Compass, can all be used as part of a new tool for ocean sensing. The future high bandwidth signals transmitted by Galileo, in particular, will enable higher resolution measurements of special interest to scientists, for example, in resolving wave heights”

GPS Reflectometry is of great interest to engineers and scientists as a cost effective means of remote sensing. Firstly, a special transmitter is not required because GPS signals are already broadcast to the Earth 24 hours a day. Also, a satellite dedicated to GPS reflectometry would only need to carry a modified miniaturised GPS/Galileo receiver and an antenna, which could potentially be accommodated on a tiny 10 kg satellite platform at low cost, enabling multiple satellites on a single launch.

The concept is shown in the animation shown to the left (this is freely available and can be embedded into blogs from YouTube).

The UK-DMC Reflectometry Experiment has also previously been used to detect GPS signals reflected off ice and, surprisingly, dry land. The value of these measurements has yet to be fully explored but they may be used as inputs for climate modelling.

A future revision of the experiment, the “GNSS Reflectometry Instrument” is now being designed at Surrey with a view to flight on a future satellite mission. It is being designed specifically to receive Galileo signals as well as those from GPS, with the intention of real time processing. Dr Unwin's final words on the matter, “The sooner Galileo is up and transmitting the better”

Competition to curb Galileo costs and timescales

nospam@example.com (Robin Wolstenholme) — Fri, 14 Sep 2007 13:28:03 +0000

SSTL’s Group Executive Chairman, Sir Martin Sweeting stated in a press release today that he believes the increased competition resulting from the June proposal by the European Commission to fund the Galileo satellite navigation system through the public sector will reduce the cost and risk involved.

"The increased competition will have significant benefits"

”The increased competition will have significant benefits,” stated SSTL’s Group Executive Chairman, Sir Martin Sweeting. “The public sector will soon be in a position to place contracts that give the European taxpayer better value for money and step up the pace of delivering the system”.

SSTL aims to support the European Commission and European Space Agency (ESA) by building on its experience gained through the successful GIOVE-A mission, to provide best value in the operational phase of Galileo. GIOVE-A was developed under a €28M contract signed with ESA in the second half of 2003. The mission’s primary aim was to broadcast Galileo signals from space so that Europe could claim the frequencies filed for Galileo with the International Telecommunications Union (ITU). The satellite was designed, built, tested and launched before the end of 2005 – on-time and on-budget. GIOVE-A has transmitted Galileo signals for over 18 months and remains the only Galileo spacecraft in operation. Following the success of GIOVE-A, ESA placed a further contract with SSTL in March 2007 for a second satellite named GIOVE-A2.

Sir Martin added:

“It’s clear that a second source of operational satellites is needed, both to provide healthy competition and to reduce risk to the schedule of the Galileo system. SSTL has begun discussions with other key European suppliers, with the aim of forming a team capable of supplying a significant portion of Galileo whilst maintaining the winning formula employed on GIOVE-A. We expect these discussions to be finalised in October, in time to provide the public sector with a much needed competitive option”.

Galileo is a joint initiative between ESA and the European Commission. When fully deployed in the early years of the next decade, it will be the first non-military positioning system to offer global coverage.

GIOVE-A transmits first navigation message

nospam@example.com (Robin Wolstenholme) — Tue, 08 May 2007 10:18:23 +0000

Earlier this week, the SSTL built GIOVE-A satellite successfully transmitted its first navigation message, containing the information needed by user receivers to calculate their position. Prior to reaching this milestone, the satellite had been broadcasting only the data needed for measuring the receiver-to-satellite distance.

GIOVE-A in vacuum chamber, ESTEC

The first Galileo navigation message was created by the navigation signal generator unit on board GIOVE-A, using content prepared by the GIOVE Mission Segment. This week-one navigation message was uplinked to GIOVE-A on 2 May from the Guildford ground station operated by Surrey Satellite Technology Ltd (United Kingdom) and then transmitted from the spacecraft to the users. The objective of the test was to demonstrate an end-to-end link between the Mission Segment and the user receivers. The navigation message is being generated for demonstration purposes only – no service guarantee is provided.

The complete radio transmission from GIOVE-A carries a navigation signal and a navigation message. The navigation signal contains the information needed to accurately measure the distance from the satellite to the user receiver. The navigation message provides the timing and spacecraft orbit data needed to calculate the time and exact position of the satellite. One of the main tasks of the GIOVE Mission Segment is the generation of this navigation message.

GIOVE Mission Segment

The GIOVE Mission Segment comprises two main elements, a world-wide network of 13 Galileo experimental sensor stations and the GIOVE Processing Centre (GPC) located at ESA’s European Space Research and Technology Centre (ESTEC) in Noordwijk, The Netherlands.

Note: The GPC is operated by European Satellite Navigation Industries (ESNIS) – the new name for Galileo Industries.

SSTL's GIOVE-A team at ESTEC

In order to generate the navigation message, the sensor stations track the signal-in-space from GIOVE-A and send the tracking information to the processing centre. The GPC computes, among other things, the precise satellite flight path and on-board clock model. It then generates a prediction of the orbital path and clock performance for the near-term future, which is the basis of the navigation message. Next, this message is transmitted to GIOVE-A which retransmits it to the user.

Aside from navigation message generation, the primary tasks of the GIOVE Mission Segment are performance characterisation of the on-board clocks, orbit modelling, and operations planning & telemetry analysis for the navigation payload.

Another validation step completed

On 12 January 2006, GIOVE A transmitted the first Galileo signals, thereby securing the frequencies allocated to Galileo by the International Telecommunication Union. Now, the transmissions are carrying a navigation message – this means that the satellite is providing information that is needed by a receiver to calculate its position.

Although the navigation message structure of GIOVE-A is slightly different, the GIOVE-A navigation transmissions are fully representative of those that will be sent by the operational Galileo system. The operating principles are identical and the achievement of the first navigation message is another important step in the validation of the Galileo system design.

GPS interoperability

Following this successful test, in the near future GIOVE-A will begin to continuously broadcast the navigation message, with the message content being updated whenever the satellite is visible from the Guildford uplink station. Additionally, the message content will be extended to include the time offset between GPS and the experimental Galileo system. Knowing this offset, the Experimental Galileo-GPS Time Offset (E-GGTO), will allow the user to build a position fix using GPS satellites and GIOVE-A.

Galileo is a joint initiative between ESA and the European Commission. When fully deployed in the early years of the next decade, it will be the first civilian positioning system to offer global coverage.

ESA press release: GIOVE-A transmits first navigation message

What next?

SSTL were awarded a second contract on March 5th 2007 for initial activities leading to the construction of a second spacecraft for the Galileo satellite navigation system. Named GIOVE-A2, the new satellite (estimated total value 25 to 30 million Euros) will be based on the company’s proven GIOVE-A technology. From now on, there will always be a European navigation satellite in space.

ESA press release: GIOVE-A2 to secure the Galileo programme

GIOVE-A transmits first Galileo signals for Europe

nospam@example.com (Robin Wolstenholme) — Fri, 13 Jan 2006 11:31:07 +0000

Technical update - Europe's first Galileo navigation signals were transmitted from space by the GIOVE-A satellite at 17:25 GMT this afternoon 12th January.

The satellite payload was commanded 'on' from the SSTL Mission Control Centre and the Galileo signals were successfully received using the 25-metre dish antenna at CCLRC Chilbolton Observatory (Andover) and the ESA Station in Redu (Belgium). The Galileo E5 and L1 channel signals were successfully decoded at the SSTL groundstation using a Galileo navigation receiver.

GIOVE-A payload switch-on at Mission Control at SSTl:

SSTL & ESA team celebrate reception of first Gailileo signals:

These milestone transmissions from GIOVE-A mark Europe's independent entry into global positioning, navigation and timing services - intended to work alongside the US GPS and provide enhanced performance.

Galileo signal spectrum received in the UK from GIOVE-A:

Gailileo navigation signals decoded alongside GPS at SSTL:

Following launch from Baikonur on 28th December, the GIOVE-A spacecraft in-orbit checkout and commissioning progressed extremely well and had been completed by Friday 6th January. These activities on GIOVE-A involved the co-operation of the ground stations deployed at RAL (UK), Bangalore (India) and Kuala Lumpur (Malaysia), which supported SSTL during the upload of the On-Board Computer software and the deployment of both solar panels, placing the satellite in Sun Acquisition Mode.

On Monday 9th January, the on-board atomic clocks and signal generating systems were checked by the SSTL Mission Control Centre and found to be performing nominally. An ESA team then travelled to the Chilbolten groundstation in the UK to prepare to analyse the first Galileo signals to be transmitted from the GIOVE-A satellite.

The different modes of Galileo signals will now be generated sequentially using the GIOVE-A first payload chain to perform the frequency filing activities. Once these frequency filing activities are completed (expected by the end of January 2006), the payload commissioning will resume with the checkout of the second and third payload chains, assumed to be performed by mid-February 2006. Additional measurement campaigns will then be carried out to assess the Medium Earth Orbit (altitude of 24,000 kilometres) radiation environment, characterise the performance of on-board clocks and perform signal-in-space experimentations.

The 660 kg GIOVE-A satellite, built by SSTL for ESA in just 30 months and 28M Euros, has three mission objectives. First, it secures use of the frequencies allocated by the International Telecommunications Union (ITU) for the Galileo system. Second, it demonstrates critical technologies for the navigation payload of future operational Galileo satellites. Third, it is characterising the radiation environment of the orbits planned for the eventual full Galileo constellation.

GIOVE-A carries two small European rubidium atomic clocks, each with a stability of 10 nanoseconds per day, and two signal generation units, one able to generate a simple Galileo signal and the other a more representative Galileo signal. These two signals are broadcast through an L-band phased-array antenna designed to cover all of the visible Earth under the satellite. Two instruments monitor the types of radiation to which the satellite is exposed during its two year mission. The Galileo signals broadcast by GIOVE-A are being carefully analysed by ground stations to make sure they satisfy the criteria of the ITU filings.

SSTL website

SSTL audio interview available for download

nospam@example.com (Robin Wolstenholme) — Thu, 22 Dec 2005 12:17:31 +0000

British satellite manufacturer, Surrey Satellite Technology Ltd, discuss the launch of the GIOVE-A micro-satellite, part of the ESA Galileo project from the Baikonur Cosmodrome in Kazakhstan scheduled for 28 Dec 2005 in an audio interview.

The interviewees are Martin Unwin, Head of the GPS and GNSS team and Andy Bradford, Project manager for the GIOVE-A satellite.

The Audio is available as an itunes mp3 audio file which will play on an any mp3 player software or hardware.

The interview can be downloaded directly by right clicking the on link below and selecting "Save target as" in Internet Explorer.

Direct link to SSTL GIOVE-A audio interview

This file may be freely distributed providing the origin of the content is identified as Surrey Satellite Technology Limited (SSTL) www.sstl.co.uk