Wednesday, January 23, 2013

Satellite world explores action on ‘jamming’

Talks between broadcasters, satellite operators and equipment makers have raised the prospect of future countermeasures to tackle the growing problem of deliberate broadcast satellite interference. 
Most interference is accidental, but malicious ‘satellite jamming’ is surging, with Eutelsat reporting 340 cases in the first 10 months of 2012 and a threefold increase overall since 2009.  Of these incidents, the satellite operator traced 90% of hostile signals to Iran and Syria.

A meeting at the headquarters of Eutelsat in Paris on Friday (18 Jan) brought together industry protagonists who have already been or fear they will be affected by jamming, to discuss countermeasures to the problem.

One option suggested is to enable satellite operators to share data about when and where malicious disruptions happen. The data would be stored in a common space for reference and used in discussions with international regulatory bodies. A start was made on creating such a database at the Paris meeting.

It is already possible to indicate the geographical source of an interfering signal, using two satellites that are well positioned to locate the source – a process called ‘geolocalization’.  With this information, the source of the interference can be found, logged, and in principle asked to desist.
The ITU Radio Regulations Board, which rules on cases of interference, continues to assess how to respond to cases of jamming, and the results of geolocalization may be a crucial factor in the course of action the ITU opts for.

Last autumn the International Telecommunication Union (ITU), petitioned by the EBU and its Members, condemned deliberate interference, which is considered a violation of Article 19 of the Universal Declaration of Human Rights.

Article 19 states that: "Everyone has the right to freedom of opinion and expression; this right includes freedom to hold opinions without interference and to seek, receive and impart information and ideas through any media and regardless of frontiers."
Also being explored is the electronic redirection of satellite receiving aerials, so that the source of the interference is placed in ‘dead point’ in the aerial’s receiving pattern. This technology is already in use on military satellites.

EBU Members and other broadcasters use satellites continuously, either to provide services to the public or to feed news, sports and other content back to base. Satellites receive signals when they are targeted by the desired transmissions, but they can just as easily be hit by unwanted, interfering signals.
Modern broadcasting satellites aggregate broadcast channels in a ‘multiplex’, so jamming of one service can also scramble numerous other channels. It is for this reason that the issue of jamming affects all satellite industry stakeholders, and not just a few select channels and broadcasters.

The sharp rise in deliberate scrambling of broadcast services, including those of EBU Members such as the BBC, Deutsche Welle, France 24 and others, has given greater urgency to the search for solutions.

Fortunately, most satellite jamming results from an innocent mistake in setting up or using transmission equipment. Unwitting signal jammers usually take corrective action once alerted to their error.

Perhaps the greatest weakness of the world’s satellite telecommunications system is that it depends, ultimately, on the good faith and conscientiousness of transmitter operators.

In February the DVB Project, based at the EBU’s Geneva headquarters, plans to publish a ‘Carrier ID’ standard that will enable a faster response to accidental interference. When correctly applied, satellite signals will carry the transmitter’s contact information – such as a telephone number – so that mistakes can be quickly rectified.

(Source : European Broadcasting Union)

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