Internet Wi-Fi is becoming the latest must-have service when airborne. Ben Ash, Special Projects Business Development at ip.access, argues that there is equally a strong case for cellular service onboard. He explains how small cell technology has evolved to deliver cellular service in the sky and highlights key differences between Wi-Fi and cellular service experience.
A major player in the sky
A substantial portion of our business comes from outside of mobile service providers. My focus is on solutions which are all bespoke and not always ground based. These range from a portable “network in a box” for disaster relief or defence applications to test and measurement and academic research.
ip.access has been closely involved with enabling GSM cellular service onboard airliners for almost 10 years, serving a significant portion of the global aviation market. Wherever you spark up a smartphone on an aircraft, it’s almost certainly using one of our products. There are two leading aviation service providers – SITAOnAir and Panasonic Aviation/Aeromobile – with over a thousand mostly wide-body long-haul aircraft fully equipped to date. Services operate seamlessly in the same way that you would use your phone when roaming abroad. This has led to quite a high take-up with Aeromobile recording that slightly more users connect through cellular than Wi-Fi as shown in the chart below. They find that these two wireless technologies complement each other, depending on type of device, needs and payment preferences.
While today this is still mostly GSM/GPRS based using global frequency Band 2 or 3, there’s no regulatory restriction on the choice of 2G, 3G or 4G. We’ve been installing 3G since 2015 and expect this to be widely deployed alongside either 2G or 4G in the medium term. Factors involved in the choice include handset compatibility and support for VoLTE – there needs to be some way to fall back to 2G or 3G for voice calls should the 4G service or handset not support it. The S60 (4G) small cells we ship today have VoLTE capability designed in from day one, even if not enabled from the outset. Several small cells are typically co-located in the aircraft equipment bay with the RF signals distributed throughout the aircraft by remote antennas.
Cellular service is enabled once the aircraft is above 10,000 feet. Voice calls can be selectivdly disabled, such as during quiet periods on night time long haul flights. Currently the US is one of the few countries that does not permit cellular service onboard, something we expect to change because there is no good technical reason preventing it.
Demand for wireless service onboard continues to grow. A recent survey by Inmarsat found that 77% of customers would pay for in-flight connectivity (up from 64% in 2016). However, as many as 60% wouldn’t bother connecting to a service that was of poor quality.
Connecting the aircraft back into networks on the ground has been a difficult and expensive operation. Satellites are generally used, delivering very wide area coverage. More recent satellite technology using the Ka frequency band has dramatically boosted available bandwidth at reduced cost. Inmarsat’s entire satellite network has over 50Gbps throughput, currently delivering up to 50Mbps per aircraft.
Terrestrial based backhaul is also coming onstream. In Europe, the European Aviation Network (EAN) complements satellite service by using ground based LTE as a backhaul. The service will guarantee a minimum data rate per aircraft and should enhance dataspeeds at reduced cost.
Free or paid service
Some airlines charge for access to Wi-Fi, which can be awkward to register and pay for. There may be security issues including spoofed Wi-Fi hotspots onboard.
Cellular not only provides secure, seamless access but also a standardised mechanism to pay for it. This operates exactly as when roaming in another country, with clear notification by text message of the charges and limits to maximum authorised spend to avoid bill shock.
Although roaming costs within Europe have now been abolished, a small premium applies for airborne use. This isn’t the penal rate from long ago and is now quite competitive with Wi-Fi or other premium services.
Inherently high quality
The quality of a Wi-Fi service can be variable depending on the number and variety of Wi-Fi devices connected. All are supported, including full backward compatibility with the very oldest, but these can significantly reduce overall radio capacity.
Cellular network design inherently provides a better experience, with all transmissions being orchestrated by a radio resource scheduler within each small cell. It can even seamlessly handover between radios should you walk along the aircraft. Quality of service at the RF link is ensured.
We also see significant opportunities to increase the brand value of major mobile networks, highlighting the extent of their connectivity by being present in the aircraft and simplifying secure access in the sky.
This could include sponsored or discounted rates, branding in the onboard magazines, introductory offers and more. It’s a relatively easy way to differentiate to a higher value captive audience for a relatively constrained timescale.
Finally, will we see 5G onboard next?
Today’s backhaul constraints make 5G less relevant. I’d expect more take-up of LTE over the coming years, retaining either 2G or 3G for backward and voice compatibility with the widest range of handsets and roaming networks.
For further insights, read ip.access latest whitepaper on the topic, available to download from here.