I tell you what smacks of Trolleyism, linking to a site with no information on it whatsoever that wants an email address and your Twitter credentials before it'll tell you what it is!
In less than 18 months' time the police radio network will be switched off. There is no obvious replacement and the looming omnishambles is turning into a bonanza for Arqiva, the only company brave enough to offer a solution. Peter Neyroud CBE, former head of the National Policing Improvement Agency and now at the University …
Switch to 4G? Don't these people ever look beyond the UK's borders? Even in 1st world countries like the US & Japan, cell systems go down in emergencies. 911, Hurricane Katrina, Hurricane Sandy, Tōhoku earthquake tsunami (also caused the Fukashima meltdown) ... Anyone relying on the cell system was SOL. Often for days, in some places weeks or even months.
Obviously, no major disasters could ever happen in the UK, so no problem.
Probably not. Most of the time they don't look beyond Westminster's borders. If you need proof, ask yourself (and them) why they're only just thinking about Not-Spots. The fact that there's a General Election coming up is nowt to do with it of course.
That can be true, but not with all mobile carriers to my knowledge - during Katrina where the entire city was under water and winds got up to 120 mph I can see it but would any other service hold in that? Or an earthquake on the 7 richter scale where mobile towers and underground cable may be damaged? Is there a better solution I am unaware of?
We have had the 3G and 4G combination for at least 6 years now. Depending on where one lives will be dependant on which mobile service works best for you. Verizon works best over all because they have the most towers and cables (I guess) and Verizon is the opnly service that works in the Rocky Mountains areas - but some other services are starting to now because they pay "rent" to use their towers - then the customer may be billed for "roaming" charges.
Here, they advertise 4G as "faster for Internet use for videos, searching the web, etc" - but personally I haven't seen any difference with my own service speeding up because of it. The less expensive mobile carriers are always going to be a bit slower than the most expensive - until a law is passed that disallows the narrowing of bandwidth a "renter" can us.
However, for myself: who does use my mobile for Facebook, watching videos aor television, etc., I am satisfied with paying $50.00 for unlimited talk/text and 2 GB of Internet use to receive important email, use Siri to get information or direction, or to perhaps do the occasion odd bit of price comparison.
MY CONCERN is that our governments may (require) these new shut down features on phones NOT so that thieves can be traced; but so governments have a way to shut down all towers in case of rebellion. If you recall it was cell phone transmissions that let the world know the reality of what was happening in Egypt a few year ago. Now THAT is definitely something to be concerned about.
thank you. I did quite a lot of work on it, although limited to the base-stations/repeaters design/build rather than handsets..
One issue with the article - it claims Airwave used to be O2 which is not quite correct. It was actually originally a consortium of BT Cellnet and Securicor Data Systems (based in Chippenham, of all places) and somebody else that I can't remember (it was a long, long time ago).
Cellnet became mmO2 which became O2 and Securicor became Sunguard. I don't think Sunguard exist anymore either.
Why not just change the supplier. TETRA is a worldwide open standard, it doesn't have to come from any one company. And why 4G? Are the police going to be surfing youtube in their free time or something? All this system needs to do is voice, text alerts and location tracking. Thats it. That sort of digital tech has been around since the 80s.
I was thinking that. Unless you're sending photos or video 7kbit/sec should be sufficient.
If they were equipping the police with live helmet cams or drone downlinks or something like that then it could make sense to use 4G. But why would you tie a power-sucking frivolity like that to the officer's main method of communication?
Roger that. If they need fast data rates why can't that be an additional 4G/WiFi handset alongside the Tetra radio? Heck if you retrofit the Tetra with a Bluetooth modem the 4G handset can use Tetra for slow rate comms when the 4G/WiFi connection is unavailable.
They want to be able to send more information between officers, for example, someone gets stabbed on the highstreet, this is caught by CCTV, it would save a lot of confusion, time and money if a picture of the perp could be sent directly to all officers devices quickly and reliably.
The reason for 4G over 3G is that 4G will (may) have multiple layers of priority for different traffic, e.g. a stabbing would take priority over someone with a missing cat.
> Maps and building plans are useful to the police but essential to fire services.
First of all thank you for the very good article. Having been a volunteer firefighter, I don't understand the requirement for online maps or building plans for fire services however. If you are on the attacking team, you will want *many* and *highly reliable* voice channels to communicate with the standby team and the command post. The command post may have a use for maps but then they sit in a lorry in the no-danger zone: They can *reliably* have the maps/plans on an offline medium such as a rugged hard drive. And they can (and probably will) guide you as they have the time to look up plans and think about ways of attack. In my (limited) experience, you don't have that time on the ground.
IMHO, most projects in this area are much too ambitious regarding "luxury" targets and forget the basics: It needs to work no matter what the environment conditions, how many users there are and what is the nature of the chaos around you. Streaming back video to the command post might be nice, but - again IMHO - is rather useless as the team inside is going to make most tactical decisions on its own based on what it sees, hears, smells and measures. We are trained for this and mainly need the channel to the CP to ask for reinforcements, supplies etc.
I've worked on Tetra handsets, its a good standard, does all the weird stuff the emergency services want, like mini basestations, walkie-talkie etc. Given that it was replacing analogue narrowband comms it had to use a very narrow bandwidth, so would never do video streaming. Tetra+ was an attempt to increase BW by using fancy 64QAM (or somesuch), but was never really going to work outside the lab.
So why not simply couple it to a GSM/3G/4G whatever phone, which duplicates the comms both for archiving and for diversity (fail-over to non-Tetra) - and allows SMS and multimedia when available.
Indeed, why not use 2 batteries 2 mics 2 speakers, like sellotaping together a Nokia and an existing Tetra handset.
Unfortunately the TETRA standard only covers the interface between the TETRA network and the TETRA handsets/devices. Internally (i.e. in between the TETRA switches) the TETRA network uses vendor-specific, proprietary interfaces. So you'll need to rip out all your TETRA switches and replace them with new gear supporting the required functionality. Nicely played by the TETRA vendors!
@Ben Liddicott: I second that. The common sense route would be to have reliable voice plus secondary potentially flakey data transmission rather than make both shite. The last thing you want in an emergency like an armed incident is a PC calling for backup like something out of a Dom Jolly sketch.
As why change the system said, nothing wrong with TETRA, but of course the buyers know nothing and the sellers are bullsh#tting.....typical civil service contract negotiation...the blind being led by the crooked. Glad I am out of it all now.
I certainly wouldn't want to be the Senior Responsible Officer (SRO) of the ESN project/network the first time a policeman dies because he couldn't get backup on his radio!!! I'm not sure the 4G radio network operator would want the reputational damage either!
There's a maybe brief latency before your selcall channel is established but once it's open the latency is basically zero in an analogue setup.
There's a world of difference between that and a whatever-over-IP cellular technology where stuff is coded, packetised, transmitted, received, routed, transmitted again, received again, error-corrected, decoded and eventually heard by the recipient.
"What's wrong with putting an audible tone in the software when the thing is ready to transmit on the network? "
Because of unintended consequences.
If the tone is long people will wait before it finishes before speaking.
If the tone is short people will miss it and not speak at all.
It requires the user to hold the device to their ear when they're planning on transmitting.
It creates an opportunity for audio feedback.
If the 'ready' tone is picked up by the mic and transmitted another party may hear it and presume they're good to speak.
A red light would be a better option that trying to signal transmission readiness through audio.
Conventional analogue radios can also miss all or part of a transmission when it is "stepped on" by another transmitter. Something happens suddenly and unexpectedly (e.g. a gunshot), and 10 people all press their PTT at once, for example, resulting in none of the messages being heard. The example of "Don't shoot" being heard as "Shoot" can happen pretty much regardless of the system in use, and is best overcome by the use of formalised words and phrases chosen to greatly minimise the chance of wrong message interpretation due to indistinct or intermittent communication. The aviation sector as well as the military makes extensive use of such standard phraseology, as an example. Long words are less likely to get lost or misunderstood than short words - hence "negative" and "affirmative" instead of "yes" and "no"
What's wrong with putting an audible tone in the software when the thing is ready to transmit on the network?
You've got it backwards according to how most people would react - the tone should be there until communication is established so that when it goes quiet, they're free to speak, just as happens in normal conversation.
The first 1920s police radio technology needed a second or so to start up, so the meaningless number "10" was prefixed to the actual message code number as wasted space
Perhaps all we need is for copies of Smokey and the Bandit to be issued to all police officers?
10-4 good buddy .....
Motorola's had that in the trunked radios in the US for a while now. Push the button and either get a long tone saying its not connected or a short chirp that it is and you can talk. Also, why put everything on one device? Radio for talking and communicating, phone or tablet with 4G for data. Spread out the points of failure and such...
"You mean like this?"
Funnily enough, exactly like that ;)
"IIRC, aviation types actually use the shorter "affirm" for yes, precisely so that it can't be confused with "negative" if the start gets truncated and all you hear is "...ative"."
If all you hear is "...ative" and you make no attempt to ask for the message to be repeated you almost deserve to be at the Hague.
Not for nothing but last time I used good old analog military radio frequencies "rodger" or the ever popular "wilco" was still in fashion which sounds nothing like negative. I really do hope our radio comms haven't been replaced with Americanisations in the name of lets all work together because it's the yankees who have this wrong, much like their salutes :)
"There's a maybe brief latency before your selcall channel is established"
Unless the CTCSS/Selcall tones are bounced through a number of base stations.
I was involved in a lot of design/rollout stuff in rural areas in the mid 80s and it got discovered the hard way that passing through more than 2 repeaters often led to entire sentences being lost (There wasn't enough tech at the time to capture/delay the audio path at each hop). Dealing with firms who wanted to run a 2-way system across hundreds of miles in rough terrain and shared channels posed all sorts of challenges in delivering reliable end-to-end comms
This was one of the drivers towards the development of tetra systems in the first place.
"Conventional analogue radios can also miss all or part of a transmission when it is "stepped on" by another transmitter."
Indeed - and for a real world example of this, air tragedy at Tenerife would have been avoided if the PanAm flight's "We're still on the runway!!!" transmission had been heard by the KLM flight or the tower.
'is still regarded with suspicion by anyone making strategic Telco decisions and has been described Michael Hayden, a former head of the CIA and the NSA as an “unambiguous national security threat”'
We only took this slightly seriously *before* we found out the *real* "unambiguous national security threat" is the NSA. Now it's some sort of funny joke. There's strong evidence against the NSA and *none* against Huawei, we in the UK should take their investments with open arms. Cautious, evidence-based open arms, but open arms all the same.
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