Newtec Smashes Long-Standing 500Mbps Satellite Throughput Barrier

Tuesday 6 November 2012
Newtec Smashes Long-Standing 500Mbps Satellite Throughput Barrier

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by Dave Suffys, Sales Support Manager at Newtec

Particularly in the current economic climate, but always really, satellite service providers are looking to get more out of what they already have, or to do the same with less. In competition with terrestrial markets it is important for satellite service providers to always offer the best possible value to customers. Advances in technology are making this possible. Research and development departments are working overtime to come up with new innovative solutions to achieve this very goal.

At Newtec, as Sales Support Manager, one of my job roles is to perform measurements and field trials with customers to demonstrate new products. We work together with our customers and the satellite operators to endorse the new technology that we are bringing to the market.

Right now we are testing one of our newest technologies, Clean Channel Technology™ (CCT), which is a potential S2 extension candidate. It consists of three things; a reduction of the roll-off factors, significantly reduced RF sideband noise and a much cleaner carrier.

Record Breaking Technology 
CCT works by applying a smaller Roll-Off (RO) percentage than is currently used in the DVB-S2 standard. Roll-Off percentages of 20%, 25% and 35% are common.

The bigger the Roll-Off, the more satellite bandwidth is needed in order to accommodate for a certain carrier rate. Implementing low Roll-Off factors allows for carriers to be spaced more closely to each other. Of course the sidelobes of these carriers will then create interference into the neighbouring carriers. Therefore reducing the Roll-Off alone is not enough, the sidelobes need to be suppressed even more, this is where Clean Channel Technology (CCT) comes into play.

With CCT one can reduce the Roll-Off to as low as 5%, increase the carrier rate in the same bandwidth and place carriers closer to each other without any degradation. In order for new technologies to be accepted by the market we need to work very closely with satellite operators.

With this in mind we visited both Eutelsat and Intelsat – two of the most important providers in the market. Without this strong relationship we would not be able to test our equipment in live real-world conditions and the operators’ would not benefit from improved service to their customers.

The process began with a brainstorm between the technicians. We started by defining an exhaustive number of test cases and performing them in the Newtec labs. Once complete we headed firstly for one of Intelsat’s largest teleport bases in Fuchsstadt, Germany.

Theoretically we knew what our latest developments were capable of, but we needed real-world proof. The Seal of Approval as a game changing organisation in terms of its influence in the worldwide satellite industry, Intelsat requires the highest performance, quality and reliability. During tests we used three equally sized DVB‐S2 carriers both with and without CCT carriers at equal or unbalanced power to simulate fading conditions.

These tests were completed with several modulation and coding configurations from QPSK up to 32APSK. We were looking to reach the never before achieved rate of 500Mbps on a 72MHz transponder. Initial results, transmitting at 8PSK-5/6 over 68Mbaud with bandwidth cancellation were promising producing a little over 320Mbps. With a few tweaks to the configuration the headline transfer figure began moving in the right direction. Two carriers of 64.68Mbaud, 32APSK-4/5 were live on air. We quickly identified ways to improve this headline figure even further and lowered the Forward Error Correction to 3/4, which allowed the symbol rate to be upped to 67Mbaud. With this we broke existing records and transmitted at 485Mbps on the 72MHz transponder.

Not quite enough to hit that important landmark of 500Mbps but still an impressive achievement and a lot learned what could be done to improve. Breaking the Half a Gig Barrier with an extremely high throughput rating achieved at Fuchsstadt we were on to our next appointment. Now with masses of real-world data we saw our opportunity to break the world throughput record again, this time at Eutelsat’s teleport in Rambouillet, and this time breaking the psychological important half a gigabit barrier. 

Breaking the Half a Gig Barrier
This is the satellite transmission equivalent of handing the keys of a Bugatti Veyron to Sebastian Vettel for him to do an unimpeded circuit of the Nürburgring. Instead of the Nürburgring it was the Rambouillet teleport, Newtec’s CCT, automatic non-linear Equalink, our new wideband modem, Bandwidth Cancellation and Eutelsat’s transponder. With this, nothing could stop us and we broke through the 500Mbps barrier at Eutelsat’s teleport in Rambouillet where, using a similar set-up during a two-way high speed backbone test, we combined our Bandwidth Canceller and next generation modem Newtec MDM6000 series to achieve a staggering 506Mbps (2 x 253Mbps) ushering in a new era of bandwidth efficiency.

What Does this Mean?
Whilst terrestrial services are often achievable at a lower cost they are not always available or the best option. Being able to offer a lower price per Megabit is central to the satellite industry’s continued prosperity. The demand for IP backhaul is increasing year on year with smartphones driving a relentless surge in the use of data services. The vast majority of mobile phone traffic now is IP-based. Even where satellite is being used as a backup, like in Asia and Africa, where terrestrial networks are unreliable and prone to failure.

Higher Service Level Agreements
The customers are still experiencing higher and higher service level agreements and satellite, as a backup, must be able to step in and bridge the gap at the same levels. Being able to offer speeds of up to half a gigabit per second are no-longer nice-to-have. They are a requirement. Needless to say that when breaking a barrier another one comes into sight.

With the upcoming extensions to the DVB standard which will enable even higher modulation modes and symbol rates plus new and more powerful satellites to be launched we are now aiming at the 1 Gbps barrier.

Our recently launched new platform certainly has got the power under the bonnet, so stay tuned!

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