We all expect to have fast internet access, but what if you moved and were told there was nothing better than a 2Mbps-capable ADSL line available? The horror.
Believe it or not that's exactly the situation that faces around 3.3 million households across the UK. You don't even have to go to places as far-flung as the Shetland Islands to be cursed with a slow connection. Areas you'd consider to be highly populated, like Milton Keynes and Slough, can have sub-2Mbps connections affecting as many as 20 per cent of households.
Up to a quarter of those living in central Wales and much of Northern Ireland also struggle to hit this download rate. Even those households that do well in these localities might not get much more than a measly 5Mbps on average.
The issue for ADSL technology is the distance from the main exchange - the further away it is, the worse the signal degradation becomes and the slower the transmission speed. Move beyond a line-length of three miles and you can pretty much kiss any ADSL connection goodbye.
The original ADSL maxed out at 8Mbps, while the now widely used ADSL2+ increased this to 24Mbps - but even as you approach a line length of 2.5 miles, speeds dip under 4Mbps no matter what ADSL technology is used. So, unless you live within two miles of a phone exchange you're going to be suffering the shame of a pedestrian broadband connection. But help is at hand…
Enter satellite broadband. From the frozen outreaches of Finland to the warm shores of Spain, with a single geostationary satellite one company can provide 90Gbps bandwidth to customers across the whole of the contient. So how on Earth does it work?
Home satellite broadband isn't anything new; back in the early 2000s consumer products offered an accelerated download-only service with upload over a standard dial-up modem. Just as a Sky dish receives a digital video stream on a set channel, so that technology can also be turned to delivering digital data for web browsing, downloads and the like.
But those were ye olden days, and technology has moved on. We recently spoke to Eutelsat, one of the world's leading satellite operators, with 29 satellites providing TV and communication services across the globe. At the end of 2010 it launched Ka-Sat 9A, which was at the time the largest dedicated High Throughput Satellite (HTS) in the world.
Built in the UK and weighing 6.1 tonnes, it's the first satellite to be optimised for delivering high-speed broadband services. Using ka-band spot beam technology, it's able to offer 20Mbps download speeds and 6Mbps upload to anyone and everyone who lives within one of its 82 spot beams - with no slowdown due to geographical location within that beam. Sitting in a geostationary orbit 22,200 miles in space the satellite orbits in a fixed position above Europe.
Beam me up
From this lofty vantage point it's able to cover most of Europe with these spot-beams. Each spot-beam covers a rough diameter of around 300 miles, and that includes coverage for the entirety of the UK and Ireland. In fact it has seven beams focused on these fair isles, which ensures that everywhere from the Shetland Isles to lonley oil rigs in the North Sea can enjoy fast internet access.
The spot-beam system enables the same radio frequencies to be reused 20 times without interference - each spot-beam can handle almost 1.1Gbps of bandwidth for a total satellite capacity of 90Gbps. Interestingly, at launch the satellite was originally rated at 70Gbps with downstream speeds of 10Mbps on the original spec sheet - but as the system has been refined since coming into operation this has been uprated to a total of 90Gbps and the new 20Mbps downsteam speeds.
The ka-band radio transmission system works at 30GHz for uplinks and 20GHz for downlinks and is key to the improved throughput - older satellite systems had to cover much larger areas in a single spot. These new narrow spot-beams improve performance in a number of ways, including re-using assigned frequencies multiple times - this enables them to achieve much higher capacity than conventional broad-beam satellites. The narrow-beams enable higher, more focused power and increased receiver sensitivity for 35 times the throughput of standard ku-band satellite coverage.
At the consumer end of the equation is a 77cm satellite dish, which uses a satellite modem that demodulates and modulates the TCP-IP network information into a suitable radio signal for the dish to send and receive.
The Tooway modem offers the usual Ethernet output, so it's easy to integrate into an existing home network or build up a new one around it. Eutelsat operates eight dedicated base-stations known as gateways to which the satellite directs the appropriate signal, and the gateway - acting as the ISP - routes signals to and from the larger internet.
Interestingly, the cutting-edge ka-band system isn't as affected by adverse weather conditions. Sky and Freesat users often find that heavy rain interferes or entirely blocks satellite TV signals, an effect known as 'rain fade'. When the ka-band system was originally deployed, it was expected to handle heavy-rain conditions well, but according to Tooway, once in full service it will be largely unaffected. This is done mainly through adaptive uplink power control and an ultimately reduced bit rate to ensure a continuous service across the board.
The one weakness that remains for satellite broadband is latency, which is something that simply can't be eliminated. Being 22,236 miles away, it takes a radio signal travelling at the speed of light 250ms just to get to the satellite. Typically, latencies bounce around the 600 to 800ms range, making the system unsuitable for gaming as even dial-up modem latencies can be as low as 120ms.
Potentially, satellite broadband can offer far lower latencies by using lower orbiting satellites - at 5,000 miles this would be down to 125ms or as low as 10ms at 620 miles. However, as these lower orbiting satellites don't stay in a fixed position, a considerable net of multiple satellites would be required to maintain a connection. But this would cause additional complexities in the receiving antenna that would have to balance bit rate against ease of reception.
Despite this, gaming is about the only service that's unrealistic for geostationary satellite broadband. Using predictive caching web browsing can be made perfectly snappy as any land-based service, while Skype and voice services work as well as you would expect .