Real Wireless plays crucial role in TalkTalk spectrum variation request to Ofcom

Screen Shot 2016-05-27 at 13.53.05You may have seen the recent news that Ofcom has recommended to change the licence conditions in the “DECT guard band” after TalkTalk submitted a variation request. TalkTalk submitted the request because the company wants to deploy low-powered 4G technology in the UK in the 1781.7–1785 MHz frequencies, paired with 1876.7–1880 MHz.

This band is already allocated for mobile operators to provide 4G services within the EU, however, in the UK, this spectrum forms part of a ‘guard band’ between spectrum used by mobile networks and that used by cordless home phones. Within the UK this has been left unused to prevent interference between the two groups of users.

This variation would permit TalkTalk to deploy compliant 4G apparatus in the band, which it has owned for a number of years now, enabling it to deploy new broadband routers that feature a 4G mobile femtocell — without the need for (expensive) additional filtering.

Earlier this month, Ofcom consulted on plans to vary concurrent spectrum access licences in this band, and expressing its preliminary view that allowing low power 4G devices in this band would be acceptable and the benefits of this use would outweigh any small additional interference impact. Ofcom’s preliminary view cited three Real Wireless reports that were commissioned by TalkTalk to conduct an independent technical study into the potential interference with uses in adjacent bands.

Evidence of the impact of a potential interference was based on a measurement campaign and co-existence analysis based on Real Wireless’s extensive modelling capability. The test scenarios also spanned from small cell spectrum emissions; to impact on voice quality, dropped call rate and call hold times comparisons of a dense DECT network; and interference with a DECT-based baby monitor.

Based on these results, Real Wireless was able to propose to TalkTalk the changes to the licence conditions that were likely to be considered acceptable to Ofcom, and formed the basis of Ofcom’s recommendation.

Bad neighbours? A comparison of LPWA technology options

Screen Shot 2016-05-11 at 10.24.43While the carrier community is celebrating the steady arrival of 3GPP defined cellular IoT that will enable the use of existing GSM networks with minimal impact through upgrades, there remains significant interest in alternative solutions in the unlicensed space.

Some of this interest comes from service providers who lack access to licensed spectrum, but the majority is being driven by use cases where the long range, extended battery life, and very low cost of Low Power Wide Area (LPWA) wireless technologies is a fundamental necessity. What is emerging though is a fragmented area of largely proprietary solutions, making it difficult for users to decide on which option best suits their particular use case.

The key approaches to unlicensed M2M connectivity can be split in to two groups: UltraNarrowBand (UNB) technologies; and those that employ some form of spread spectrum modulation (SSM).

Growth forecasts for the M2M market underline the need for these LPWA systems to be able to co-exist in license exempt spectrum and that any LPWA solution should be able to support  many connected devices – and this requirement is only going to become more important over time as the number of devices increases.

Real Wireless recently carried out a study that compared the levels of interference between networks using these two different physical layer architectures. This required us to model a scenario in which a UNB and a SSM network had overlapping coverage areas and various other sources of interference, including non-LPWA users, in order to study the ability of both technologies to mitigate interference.

This insight gained was that UNB and spread spectrum modulation networks can only effectively co-exist in very low capacity deployments. Shared channel operation, either between a SSM and a UNB network, or two SSM networks, would result in mutual interference and uplink blocking of both networks, except in cases of very low simultaneous user numbers.

In other words, the reality is that a SSM LPWA network architecture should be considered a ‘bad neighbour’, and multiple unlicensed IoT networks can only effectively share access to spectrum when they all also share a UNB architecture. However, given the number of use cases for these technologies, they will undoubtedly coexist in one location. As a result, this study has significant implications for technology choices in this important growth market.

To find out more about our study and approach to modelling of unlicensed IoT solutions, download our new white paper today.

There’s a lot of work to do to get acceptable connectivity on trains…

Cmglee_London_Kings_Cross_platform_6Everyone on trains has, at one point, suffered from poor connectivity on their phone, tablet or laptop when working while commuting, trying to access social media or catching up on the day’s news.

Poor on-board connectivity has become a fact of life at the moment, and consumers are becoming increasingly agitated at their inability to receive the same quality of connectivity on trains as they do at home. Nor is this frustration without justification; if the population could receive reliable connectivity onboard trains, it would likely create value for not only passengers and train operators, but the wider economy as well.

It’s therefore no surprise that the government has been vocal on this topic, calling for consumers to be able to receive a similar level of mobile voice and data access on trains as they do in urban areas — irrespective of service provider. The government has attached a specific target to this demand — Wi-Fi on 90% of journeys by 2018 — but, when you consider that just 62% of British rail routes currently have mobile coverage let alone Wi-Fi, you can see there’s still a long way to go.

What many consumers are unaware of when they complain is the sheer expense and complexity of providing reliable connectivity on trains, something we’ve blogged about before on this site.

What’s the industry doing about it?

I recently chaired the inaugural Gigabit Train event at techUK to discuss the technical and commercial challenges of providing wireless connectivity to trains by 2020. At the event were a number of rail wireless providers, including Nomad Digital and Fluidmesh; a satellite provider, Hispasat; the Department of Transport; and Ofcom.

I wrote an article for techUK on my first set of impressions from the workshop: that the technology required for wireless on the railways is starting to get better. However, I wanted to take the opportunity to follow up by considering another issue highlighted in the discussions; the amount of investment necessary to get mobile connectivity to an acceptable standard.

The crux of this problem is that the industry still needs to establish a business case for on-board connectivity. Without one, there is no commercial incentive for train companies to improve standards beyond their current level, especially when many train companies see Wi-Fi as a drain on resources.

A few years ago Real Wireless examined how such a business case could be constructed, for the RSSB. Our report found that, done correctly and efficiently, there’s actually a very clear opportunity to build such a business case — though it must look beyond Wi-Fi to mobile connectivity as a whole. The business case would need to encompass how to:

  • Get advertisers on board and set expectations for ad revenue based on the length of passenger journeys
  • Extend the benefits of connectivity to train companies themselves — as well as their customers — so they can make day-to-day train operations more efficient
  • Introduce new services and applications with a potential ‘killer’ app to improve the passenger experience — because relying on big data isn’t sufficient

With enough of a common view of the viable value propositions of these components the industry can tackle the next significant hurdle: achieving economies of scale by getting stakeholders to agree on a scalable solution and revenue model — something that will prove particularly difficult in the UK’s franchised rail network.

How to make progress? There is no doubt that the rail companies are a significant stakeholder; as part of their digital strategy they should drive the initiative and lead on establishing value chains that point to a sustainable business case. But the mobile operators also have an important role to play, establishing backhaul that is capable of supporting this solution.