Cassidian’s broadband path for public safety

Europe is struggling to find a way to bring broadband to TETRA and TETRAPOL networks. But Cassidian and Alcatel-Lucent have come up with a solution that could provide access to broadband services in the short-term

Cassidian’s broadband path for public safety

Mobile broadband data services are now widely available to consumers in the developed world through their laptops, smartphones and now tablets.

The problem for most public safety organisations is that their dedicated mission critical narrowband networks, be they TETRA, TETRAPOL or P25, can only handle voice and a limited, albeit useful, amount of short data.

While Cassidian offers TEDS to boost the capacity of TETRA networks, streaming videos of an incident to police, ambulance and fire crews requires a broadband solution.

The need has been recognised in the US, where the federal administration is providing dedicated spectrum and funding for a separate broadband network to overlay the existing P25 voice network.

Funding two separate networks is an expensive option and cash-strapped European nations are highly unlikely to be able to afford this option in the near or even medium-term future.

Political mandate

Philippe Devos, VP market and technology, secure communications at Cassidian, asks: ‘So, how do we bring new efficiencies to public safety? If you look at the political mandate there are not very many options. More police on the street? That’s difficult with the existing budgets and there are only a limited number of cameras you can put in the street. That leaves you with technology.’

Devos points to the huge growth in mobile connectivity over the last five years. ‘The challenge is to lift up mission critical networks to this level of connectivity. But for European markets, can you have two parallel networks for a while and merge them later? I don’t think we can afford it, unlike the Americans. We need to upgrade existing systems.’

Broadband trials

He points to a conundrum where Cassidian together with others have lobbied European regulators to get dedicated spectrum for public safety customers. Regulators point out that there is no broadband technology in the 400MHz band. Cassidian’s response is that while this is true, unless spectrum is made available, there is no business case to develop broadband in the 400MHz spectrum.

Cassidian decided to tackle the problem by forming a partnership with Alcatel-Lucent to provide a broadband solution within the existing PMR spectrum band, which was announced at the TETRA World Congress in Budapest in May this year. Trials are due to begin in 2012.

The tricky bit is that spectrum has to be refarmed to allow the Cassidian/Alcatel-Lucent solution to work and provide the new efficiencies that will keep policemen on the street.

Devos acknowledges that a European survey into the requirements of the Public Protection and Disaster Relief (PPDR) community defined a need for 2 x 10MHz of spectrum for broadband, in addition to the spectrum they have today.

‘This is the goal, but our customers would like to start using broadband now. And they can start with 2 x 1.4MHz or 2 x 3MHz. It opens new possibilities for customers to boost capacity for public safety mission critical infrastructure,’ he says.

New spectrum

Devos argues that Cassidian is being pragmatic and that the search for dedicated new spectrum should go on, but warns it is unlikely to happen quickly. ‘The US has broadband available in 700MHz, but that decision was made in 1996 by Al Gore, so it has been a 15-year journey to allocate and get this spectrum and they are not quite there yet.’

The PPDR community in Europe missed the first digital dividend, which went to the powerful TV and mobile operator lobby. There may be a second round after 2016, with frequencies available perhaps by 2025 and some military spectrum may also come available, but it could be a long wait.

‘The technology allows you to start with a narrower channel. People confuse the need to find 2 x 10MHz for broadband in the future, but we can start now with 1.4MHz. Will it be enough?’ asks Devos. ‘No, of course not, but it will provide flexibility for a refarming.

‘To get the benefits spectrum needs to be reorganised. We are not saying stop using the narrowband, just reorganise the existing spectrum to allow for some broadband,’ he says.

Naturally, refarming spectrum is a touchy and controversial subject, as existing users don’t like to be moved onto different spectrum. But Devos points out that the current management of spectrum is not necessarily the most efficient way of allocating this national asset. ‘So, before anyone asks for new spectrum they need to justify what they are doing with existing spectrum. We need to optimise every bit and herz we have.’

He observes that the military owns spectrum in 400MHz, but says this need not be a hindrance to Cassidian’s refarming case. It might even be an asset.

‘The military’s software-defined radio programmes are very expensive and they too have less and less money to play with. So, all the security organisations and the military will be encouraged to look
at commercial technology,’ he points out.

He argues that Cassidian’s technical investment in 400MHz might be relevant for the military too, because if they use it that will help widen the ecosystem, which makes it more cost-effective.


It might also make the military more amenable to sharing their 400MHz spectrum with the PPDR community. After all, the military often has to work with the PPDR community, so ease of interoperability between the two is vital.

Devos also believes that by investing in broadband technology now, in however limited a way, will help prepare both manufacturers and end users for the time when broadband technology becomes much more widely available.

‘We have to prepare for the evolution of TETRA and TETRAPOL,’ says Devos firmly. ‘It will be based on this type of technology, although it will keep the functionalities of TETRA systems that are not available on current LTE systems, such as fall back modes that are a must for mission critical networks.’

The US’s 700MHz LTE broadband option has some drawbacks, according to Devos. ‘What is important here is that LTE is low power. You can overlay P25 for vehicles because they have good antennas and you’ll get good coverage outdoors. But if you want to provide coverage to pedestrians then you have to multiply the number of sites by three or four times to provide the same amount of coverage to reach mission critical levels. That is fine if you get the money from the federal administration!’

In contrast, Cassidian’s proposal for 400MHz in Europe is a high power solution, ‘so we can get a one-to-one site reuse: the same site for TETRA and broadband with the same coverage,’ says Devos.

‘Look at the economics of a network,’ he says, ‘a lot of money is put into building the backbone, getting the sites and making them secure, air conditioned and protected. Those sites can last forever, so let’s reuse the sites and share networks. We can use the same teams to upgrade and maintain the sites – it’s more efficient.’

Devos acknowledges there is not yet a consensus on the solution going forward and that other technologies such as DMR and dPMR are vying with TETRA and TETRAPOL. For a consensus to happen, some spectrum for narrowband users will have to be secured.

‘But we have opportunities in the 400MHz spectrum now,’ argues Devos. ‘Do we just wait 15 years and hope to get some of the next digital dividend spectrum and increase the cost of corresponding networks?’

Devos is clear about the function of broadband technology. ‘The purpose is not to bring internet access to the police – that will not solve anything. The purpose is to manage the information within the context of an incident. It is a challenge to manage CCTV feeds, passport information, medical information on a casualty and so on. Who is going to do this?’ ask Devos. ‘Suppliers can help, but it is a change management issue too. Someone has to select the right information and send it to the right people at the right time.’

This is where an LTE system, especially one reliant on a commercial carrier, is problematic for mission critical purposes. Yes, LTE can do voice, but it cannot provide direct mode or prioritise what information takes precedent and to whom it should go first.

‘LTE feature prioritisation at 3GPP is done for mobile carriers,’ says Devos. ‘With the PMR industry we will work on broadband and respond together to the requirements of public safety. Then we will collectively manage the broadband evolution for the professional markets.’

Written by Wireless magazine
Wireless magazine

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