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Showing posts with label TETRA. Show all posts
Showing posts with label TETRA. Show all posts

Friday, 7 June 2013

3GPP Public Safety focus in Rel-12


Public Safety is still a hot topic in the standards discussion and on this blog as well. Two recent posts containing presentations have been viewed and downloaded like hotcakes. See here and here.

3GPP presented on this topic in the Critical Communications World that took place last month. The following is from the 3GPP press release:

The ’Critical Communications World’ conference, held recently in Paris, has focused largely on the case for LTE standardized equipment to bring broadband access to professional users, by meeting their high demands for reliability and resilience.
Balazs Bertenyi, the 3GPP SA Chair, reported on the latest status of the first 3GPP features for public safety, in particular those covering Proximity services (Direct mode) and Group call. He spoke of the need to strike a balance between more or less customisation, to make use of commercial products while meeting the specific requirements for Public Protection and Disaster Relief (PPDR).
To ensure that these needs are met, Balazs Bertenyi called for the wholehearted participation of the critical communications community in 3GPP groups, by sending the right people to address the technical questions and obstacles that arise during the creation of work items.

A presentation and video from that event is embedded below:




For more details see here.

Wednesday, 16 March 2011

Direct Communication between devices in case of disasters

Yesterday, a discussion started after I read this article on RCR Wireless News:

As in every major disaster, communications networks quickly showed their inherent weakness in times of greatest need. Japan's NTT Communications reported outages affecting Internet voice data that relies on IP-VPN technology.

In a brief statement, the operator apologized for the "trouble and inconvenience," following the string of earthquakes and significant aftershocks that rattled nerves and buildings throughout much of Japan. Some communication services are no longer available, NTT said, and telephone service, particularly long-distance service, is showing strain as well.

Service disruptions have been reported by all three of the major mobile operators in Japan, according to BusinessWeek.

This prompted me to ask on Twitter about which technologies are available that can help the mobile network cope with these problem.

Here are few approaches:

I blogged earlier about Multihop Cellular Networks (MCN) and ODMA. These technologies have their own limitations and problems and I have not heard of anything more about them being standardised or adopted.

Another post was on Ad-Hoc Networks that can be formed in case of failures resulting in Mobile devices being able to communicate directly without the need for network or base stations. The slight problem is that this approach replies on WiFi being available which may not always be the case.

A colleague suggested that in Tetra, Direct Mode of operation is available that is intended for situations like these. A presentation is embedded below:



Steven Crowley on twitter suggested that 802.16m has already started working in this direction. I got a related presentation on that which is embedded below:

Finally, Kit Kilgour mentioned about DSAC (Domain Specific Access Control) whose intention is to discontinue the voice service in emergency (to avoid congestion) but continue the packet domain normally. I have not looked at DSAC on this blog but in LTE instead Service Specific Access Control (SSAC) is used since LTE is PS only. See the blog entry here.

Please feel free to add any more information on this topic in the comments.

Tuesday, 20 January 2009

Emergency Phone Network enabled on the London Underground


Airwave has completed its deployment to all 125 below ground London Underground stations - within budget and ahead of schedule.

The complete roll out of the terrestrial trunked radio (TETRA) network on the Tube means that British Transport Police, Metropolitan Police Service and the City of London Police will now be able to use the same radios underground.

Police Minister Vernon Coaker welcomed the completion, saying the system was now fully functioning ahead of schedule, and would help frontline officers carry out the work they already do in tackling crime.

Tim O’Toole, managing director of London Underground, said the roll out was achieved five months ahead of schedule.

Airwave, a Macquarie investment fund venture, won the contract to provide access to its TETRA network in January 2007. The National Policing Improvement Agency managed the roll out, linking the emergency services to London Underground’s Connect digital radio system.

The Connect system forms part of a £10-billion investment programme by Transport for London. And the TETRA Tube roll out was initiated after the London Assembly called for improved public safety communications underground in its report into the 2005 London bombings.