Spotlight on HTS

High Throughput Satellites have become a familiar phrase throughout the industry, and although it was a hot topic a year ago, it’s even hotter now. Operators are all set to launch new satellites with high throughput capabilities, and equipment manufacturers are having to design equipment to ensure efficient transmission.

At the recent GVF Satellite Hub Summit, HTS was one of the most important topics on the agenda, and panellists discussed how it could positively affect various verticals.

For instance, SES has invested $1bn in three satellites, namely SES-12, SES-14 and SES-15. The forecast for now projects about 600Gbits of excess traffic from consumers, and by 2017 that figure is expected to rise to 1800Gbits. The satellite operator is looking to provide more flexibility by providing open architecture solutions, but also continue selling closed architectures, so customers could buy megabits.

Gez Draycott, Senior Manager, Sales Engineering at SES says: “The drivers we are seeing boosting the need for high throughput are because of a massive increase in the 3G market. Aeronautical services too are already asking for about 10-15Mbits, compared to 3Mbits of capacity a few years ago. Applications are driving this. Gone are the days of just texting, now consumers want video, Facetime and gaming.

“The HTS perspective that we are looking at is that with SES 12, 14 and 15, we can cover the entire globe with high throughput capacity. Also included in this is O3b; with O3b the latency is actually halved, so that quarter of a second that you see with geo-satellites is halved. As mentioned with backhaul, gaming and videoconferencing this is a very important factor,” says Draycott.

SES-14 has 40 Ku spots and SES-15 has 55. These are the broadcast beams as well which will allow the satellite operator to deliver live video content to aircraft, and Draycott thinks this would probably be a differentiator for SES.

“These beams are also fed by Ka teleports, saving us valuable Ku capacity, but also as an example with SES-12 we have a Ka beam over the Middle East, which would mean we could offer Ka for broadband solutions, and also very high powered Ku for solutions between two or three beams. Another valuable feature of this is multicasting. We can provide flexibility, where you can come up on a Ku beam from one of the small Ku spots, and we have digital processors on board that allow us to multicast that content to all of the beams,” says Draycott.

With O3b completing its constellation with 12 satellites, it can provide very high throughput on a per beam basis. Draycott says this can be used for maritime, where the beams follow the routes for the vessels and provide very high throughput to them.

From the perspective of an equipment manufacturer, Mark Lambert, MD Europe and VP Sales and Marketing at Advantech Wireless says that manufacturers need to rethink their strategies, when it comes to HTS.

“We need to think about what solutions we can offer. Advantech’s point of view is that simply putting up a huge amount of capability into orbit, is not the final position in terms of improving costs and bringing down solutions to the end users. We believe there are many innovations that can happen on the equipment side of things that can be brought into the market,” says Lambert.

Advantech Wireless is addressing the forward and return links to see where maximum efficiency can be found.

“These High Throughput Satellites have much broader bandwidth than satellites we’ve known in the past. A typical Ka-band satellite can have up to 500MHz of transponder space, per transponder. Our analysis shows that you can be much more efficient at transmitting over the satellite, if you are completely saturating that transponder, with a single carrier, rather than sprinkling many smaller carriers across it that need to operate at lower power in order to lower interference between them,” adds Lambert.

Advantech Wireless is deploying technology that will allow terminals take in a single 500MHz carrier, which in itself can deliver 2Gbits of data to subscribers on the forward link, as well as transmit in the return direction up to 40Mbits of information. What the manufacturer has done to develop this is to build the modem into the transceiver, hence not requiring the need for separate outdoor and indoor units.

Lambert says: “The other thing that we’ve looked at in the return link is that for many years we were looking SCPC connections. Then there was TDMA, and chopping the bandwidth and multiplexing the data across individual channels. This is great for internet connection, but not so good for streaming of data. So Advantech Wireless have taken that further and we dynamically change the technology that we’re using for return links from the remote subscribers according to the type of data that they have.

“For bursting data, VoIP or web traffic, then we use TDMA. For streaming like video and file transfers SCPC is more relevant. So our terminals dynamically switch between SCPC and TDMA according to the demands of the application and the instantaneously demands of the data that’s being transferred. This guarantees the most efficient use of the satellite bandwidth.”

Patrick Wong, MD, Asia Pacific and MEA for Sales at Comtech EF Data agrees and saying innovation is key to drive HTS to its ambitious rollout.

“We need to see what product innovations need to be made so users can fully utilise the power of HTS. High Throughput Satellite has allowed service providers to address the record growth in demand for connectivity, and also expand the scale and scope of satellite communications. With HTS I think there is a chance because the dollar per bit delivered to the customer is going to be a lot lower. There is a lot more bandwidth available and lot more data can be delivered to the end users. This also will have some characteristics, as there will be more spot beam usage for consumers, and that creates challenges for equipment manufacturers like us.”

He thinks the question to be asked is how to deliver the maximum that HTS has promised to the world?

Wong says: “HTS is coming around the corner. Some will be operational by 2016, O3b have theirs now, so when a customer buys equipment they will be looking for something that will satisfy today’s requirement and yet, when HTS comes around they need to be able to take advantage of the bandwidth available. That really is key for any equipment manufacturers today.

“The equipment has to be able to adapt to various kinds of HTS systems. Thus innovation in the brand equipment design is what the market will focus on. Quality of service, quality of experience and affordable price is what every customer is looking for. In order to do that transmission efficiency is absolutely essential. You need to use the least amount of bandwidth to transmit the maximum amount of bits. We as an equipment manufacturer should allow the user to understand more about the traffic being carried on a network, and how it can be optimised further,” adds Wong.

Nicolas Bravalle, VP, Global Data Sales and Commercial Development at Eutelsat sees HTS being invaluable for rural connectivity.

He says: “An interesting aspect of rural connectivity is that it is driving new traffic, mostly in Ku-band and Ka-band, and this is where high powered Ku-band beams with HTS will probably deliver these services. We’re also looking at smaller and lighter antennas and as we are moving along to these new services we can see the evolution of the equipment, to always cheaper, lighter and lesser in terms of consumption. This is a growth area for HTS.”

A lot of applications today are delivered through standard high power Ku-band beams, but very soon Bravalle thinks we will see these on Ka-band beams or Ku-band HTS, with an increase of traffic. In these cases one of the leading factors would be the energy consumption on the satellite, with the availability of solar panels. This is technology that is evolving quickly too.

“Continuing on from rural connectivity, we are seeing a trend where a lot of mobile operators are now letting us know that they’d like to move some of the C-band capacity, traditionally used for GSM backhaul, onto Ku-band, so that they don’t use two networks. This is also where we see a shift in the industry, where we are taking advantage of high-powered Ku-band HTS and also using technology such as adaptive coding modulation. We do have traditional internet over satellite services. As we develop the orbital position, people can expect that all this traffic will move on to HTS. This is the evolution in today’s market.”

In conclusion Bravalle says: “In mobility, there is a dramatic increase of traffic. The shipping industry, government and military mobility, yachting and fishing industry and the cruise industry is also where HTS will make a difference. Similarly we are also active in aeronautical mobility, with large commercial aircraft and also private jets.”