All posts by scsprogramme

E.T. phone home

Last Friday (Nov, 21) we were lucky enough to visit the Aussaguel-Issus teleport. The menu was fabulous: large dishes, huge interconnects and monstrous waveguides.

And the cherry one cake was the weather. Wonderful.

Thanks to the teleport staff for organising this nice visit.

A visit to the Aussaguel-Issus teleport
A visit to the Aussaguel-Issus teleport

The next Big Thing

We are happy to announce that Télécom Bretagne, Télécom ParisTech and INPT ENSEEIHT have partnered under the auspices of Institut Mines Télécom in order to produce a MOOC on satellite communications. This is made possible thanks to the support of  Patrick Drahi.

MOOC stands for Massive Open Online Course. Yes, a free online course covering all aspects of satellite communications from signal processing to the complete system.

The course is due to open in Q3 2015 in French,  Arabic and English are also scheduled. We’ll extensively rely on demonstrations using actual equipment to support the lectures.

We’ll keep you posted with information during the next weeks and months.

Stay tuned !

MOOC stands for massive open online course
MOOC stands for massive open online course

Happy new (academic) year

Here we go again !

On September 15, 2014 we inaugurated the 2014-2015 issue of the SCS programme. 18 students (from 8 different countries)  are attending the programme this year.

And yesterday (September 23) we organised our – now traditional – “networking dinner” where SCS veterans (read: former students) meet new students.

Time for discussions, calzone pizzas, moussaka and chocolat cakes !

Networking Dinner in the Quasimodo pizzeria

Antenna Install Party: take 2

We are back with the Antenna Install Party and we made it !

First to make things easier, we got a trailer. Now the antenna can be handled by a single person, if necessary.

The antenna on a trailer
The antenna on a trailer

With Damien R. (thanks!) we conducted some extensive testing, finding the best place to ensure line of sight, checking with the LNB polarization and – lastly – mastering the TV demodulator.

Here is a series of snapshots showing the antenna in auto-deploy mode.

The antenna in deployment phase
The antenna in deployment phase

And eventually we made it. By that time, it was night.

You can’t imagine the number of TV channels “free to air” available on HotBird 13.  And here is the proof of our success in mastering space technology.

"Soccer from space" in the middle of the night
“Soccer from space” in the middle of the night

Yes, this is correct. The ultimate proof of successfully receiving a radio signal sent from space over a distance of about 36 000 km is … soccer. So disappointing.


Teaching and software defined radio: a short survey

We are currently engaged in writing a conference paper about the use of software-defined-radio for satcom teaching.

In order to support our findings about this interesting experience, we have issued a quick survey to our (former) students. Thanks to their incredible reactivity, we managed in a couple of days to gather 21 answers out of 25 polled persons  (thanks !).

We feel it’s interesting  to share the results with you. They are summarised here: survey_20140513-10-21-19.pdf.

PS: as a side note, commenting is now enabled starting from this post.

AIP : the hangover

Yesterday, we held our antenna install party.

Don’t be confused: it was not a party according to the common standard where food, drinks and dance are required. Nothing of that sort: only antennas, coaxial cables and spectrum analysers. But we had fun and that makes it a pretty good party.

Still, I feel a sort of hangover considering that we did not manage to receive properly TV programmes.

There are two reasons for that: first, we have to find a better spot for our test sessions, one that is providing full line of sight. The second reason could be summarized as “RTFM” …

To conclude: we managed to make the antenna aquire the right satellite, but the signal was somewhat 10 dB short of power in order to be demodulated. Maybe an issue with the LoS which was … borderline to say the least (more line of sigh than line of sight from an antenna standpoint).

Thank you to Joan V-J., Pierre G. and Yannick D. – former students from SCS – who were my party mates for that nice evening.

Another AIP – second take – will be scheduled soon.

And now a couple of pictures (courtesy from Yannick D.)

The best spot we found to ensure line of sight ... to be improved
The best spot we found to ensure line of sight … to be improved
Our mobile "test rack"
Our mobile “test rack”

Antenna install party

We have received our new toy : an auto-pointing antenna from AVL (many thanks to Com-Ip for offering us a good deal).

Here is a picture of the antenna being deployed in the lab.

AVL auto-pointing antenna
The AVL auto-pointing antenna

In order to celebrate this event, we have scheduled an “Antenna Install Party” on Tuesday April 15, 2014 at 19:00. This will be the opportunity to test the antenna outside and assess the auto-pointing capabilities.

The meeting place is at the Télécom Bretagne Lab. If you want to join in, drop me a line (this is Laurent speaking). Note that there will be a  confirmation depending on weather conditions.

Looking forward meeting you there.

[Update as of Sun, April 13: the weather forecast tells “all sun” on Tuesday, so the install party is confirmed]

Clouds across the Moon

You certainly remember this song from the 80’s (but do you ?) featured by RAH Band.

For your recollection, here is the lyrics plot: a wife calls her husband who is on space mission close to Mars. The voice call goes through a deep space link which – this is lovingly old fashioned – is established by an “intergalactic operator”. After a couple of chit-chat, because of “violent storm conditions in the asteroid belt” the voice call is shut down. End of the story.

RAH Band's single "Clouds across the Moon"
RAH Band’s single “Clouds across the Moon”


Assuming that we are referring to a Voice over IP link, “Clouds across the Moon”  raises an interesting point. How robust are these space VoIP communications when faced with fading, jitter and other impairments ? This is precisely the problem that Alexandre V. and Gaëtan F. have been tackling during project #3 “Applications & services”.

They set up a complete VoIP system with PABX and IP phones, fed the resulting trafic in our satellite channel emulator and did quite an extensive study about qualitative and quantitative performance.

Everything is summarised in their e-report.  It is certainly worth reading it, as their work is simply awesome.

Making the weather better

We already told you : we love to check the weather from a satellite perspective. Justine S. and Pierre L. (currently enrolled with the SCS programme) are working on how to improve the processing the weather images. So far, they achieved quite nice results.

Here is what we had before, with our plain and rustic processing:

Florida, plain image processing
Florida, plain image processing

And here is the same Florida after some enhanced processing (we’ll speak about what sort of enhancements in a later post):

Florida, with enhanced processing
Florida, with enhanced processing

At first glance, the original picture may seem to deliver a better contrast, but look at the details: line synchronization and noise within the image. The improvement is striking. They even took a (somewhat wild) walk on the color processing side:

Florida, fake colors
Florida, fake colors

But that’s a different (psychedelic) story …