Cellular repeaters: Can you hear me now?

Operating or installing an unlicensed radio transmitter can get you a year in chokey, or six months if you're lucky enough to be in Scotland, and El Reg would never condone such activity - so please enjoy the following work of speculative fiction. A cellular repeater is a base station, but one whose only connection to the rest …

[baswell]

Passive ones won't land you in jail

You can always use a passive one. Hill obscuring your reception? Take two antennas both tuned to the 900/1800 and connect them to each other. Set them up on the hill and point one at your house, the other at a cell tower.

Chances are that's all you need; no expensive equipment or law breaking required.

[Ben Park]

Surprising

...the network operators don't actively encourage this, and perhaps even send their own hired goons to install them outside on a nice long pole.

It's for their benefit after all, and they're not even paying the electricity for them.

I know Orange paid quite a lot of money to have an antenna installed at Wookey Hole Caves, and consequently it's probably the only middle-of-nowhere underground caves in the world with full signal and 3g access. No signal on any other network anywhere nearby except the car park.

Paris, because she'd look good on a pole.

[Anonymous Coward]

would look into it and let us know

Operator-speak for "we don't bloody know... go away kid, you bother us"

[Anonymous Coward]

Does not compute

I phoned Voda about a year ago to complain of the poor reception in my office building, and was told (after jumping through several hoops) by their technical guy that they could send me a "signal booster", which I could plug into a power socket, put on my desk, and it would ramp up the signal for my phone and all Voda handsets in the surrounding 100m radius. This unit was, I was told, to be sent at no cost to myself, and would resolve the problem until the area coverage was 'upgraded' by a normal transmitter.

Unsurprisingly (if they're illegal) the repeater did not ever turn up, despite me chasing for 2-3 months after this promise. It's not an issue now, as 3-4 months ago my signal popped up to 5 bars and full HSDPA, so I don't need the booster anyway.

Seems funny, though, that they'd promise a £400 device which is apparently illegal to a punter over the phone....

Paris, 'cos she likes repeaters.

[Anonymous Coward]

Think fast

Well if the network operators have any sense, if someone comes to you saying "I'd like to buy (at my own expense) a piece of equipment which means I'll get a good signal on your network and not have to move to another provider", I think you should answer YES PLEASE DO! pretty sharpish...

[fifi]

repeating repeaters?

A couple of Qs about these.

Would a repeater recognise another repeater as a "base station"?

Do the repeaters simply forward the entire signal, or is there any specific requirements for 3G signals?

[Anonymous Coward]

Repeater on not a repeater

I'm not entirely sure if this device classifies as a repeater. It does not actually extend the coverage beyond that of a provider’s base station. It just 'tunnels' the signal (both incoming and outgoing) through an obstacle.

[Jonathan Schofield]

Just what I need

I have an insatiable urge for an IPhone, sad I know but O2 does not work too well where I live and Vodafone is the only working alternative. Because of this I was first in the queue for the Blackberry Storm with which I am sorely disappointed. There seem to be too many software glitches and I have lost a few calls and called a few wrong numbers due to Fat Finger Syndrome. The IPhone is just so much more sexy.

This lust for technology is crazy, when I was at school the pocket calculator did not exist and "photocopying" was done with a hand powered Xerox machine utilising a form of carbon paper wrapped round a drum. It was a punishment duty to crank out the copies and then clean the machine; I soon became an expert.

[Anders Halling]

Illegal for a reason.

Hmm.

The ability to route other peoples data through your own equipment and perchance keep a copy for yourself.

Wonder why this is illegal...

[Anonymous Coward]

@Anders Halling

Yipes. I fear for the future of routers and mesh networks should you gain power.

[Anonymous Coward]

@AC: "Does not compute"

"Seems funny, though, that they'd promise a £400 device which is apparently illegal to a punter over the phone...."

Try reading the article properly.

[Cameron Colley]

"Installing or using..."?

Installing, owning, deploying, whatever... I can understand -- but are you implying that these are illegal to use even if your operator gains approval from any necessary regulatory bodies and has it installed?

[Nick]

@Ben Park

You're probably right - Tora Bora probably have to make do with Satellite Phones or Camels.

[Marc-Oliver Kalis]

Operators need to keep taps on them

Itś quite simple, eve nthough there is a good coverage, since it only repeats, you can potentially onnect more phones onto a single basestation.

if the repeater is too strong, a multitude of phones will connect to it and thereby reduce the service quality (typical symptom: ¨Network Busy¨.

so I can understand, when there is a reluctance to push out too many repeaters, since it can negatively affect your network

[Steve]

@Ben Park

When I got a tour of the LHC a few months before they started looking for God I was very surprised to find no fewer than 6 networks appearing on my phone, despite being a looong way underground. I could even connect to some of them ...

[Anonymous Coward]

Technicality

It's a bit of a technicality that they are illegal really. In-car iPod FM transmitters were illegal until their use was specifically legislated but I doubt anyone was every prosecuted using one? I believe they were only made legal because there were so many of them. Hopefully these will go the same route - but I think I'll wait until type approval. Not sure I would want a high power 2.4Ghz transmitter in my house apart from the Microwave Oven.

[Anonymous Coward]

Congratulations....

to all you Mobile Phone FanBois...

Ur all gonna get Cancer!

oh-oh-oh i wanna base station in my house!....

yeah and looks like u need some ready made boxes for the wife n kids, cos ur all gonna need them...

oops its Xmass!, well looks like ur gonna get the boxes all round, at least ;p

grrrrr.....

gimme a 5W Jammer and a nice inconspicuos mast, hidden on the side of the block of flats amongst the numerous sky/VM black cables....

so. thats 920, 1.7-1.9, 2.2-2.5, 5-6Ghz all nicely damped......

now...

wheres me TinFiol........

[Anonymous Coward]

@Operators need to keep taps on them

There is another good reason as well, in addition to the potential to connect more phones to a cell than it's dimensioned for.

A lot of work goes into ensuring that adjacent cells do not use the same or overlapping channels as the resulting interference would be a 'bad thing' - extending the range of a cell with ad hoc repeaters has the potential to undo this RF engineering work in a city environment and cause interference to other cells.

[Charles Smith]

Even more useful

An even more useful device, but equally illegal in this country are mobile 'phone jammers. They work well and would be ideal in theatres/restaurants.

Ah well off to Qinetiq for some of their passive mobile phone signal suppressing wallpaper.

[Dave]

Arrests and charges are not prosecutions

I wonder how many people have been prosecuted though, as opposed to arrested or charged, both of which are only used when there's some necessity, to prevent further offences, or take someone dangerous away from the public.

There's not many people arrested or charged for speeding either but thousands of prosecutions for it.

I say that as an interested party by the way, I would gladly pay £300 for perfect reception at my house which is just a bit too far to get decent signal quality anywhere but the kitchen.

If <insert mobile operator here> would give me permission I'd snap it up. After all 250 sqm is only a 9m radius so unless the cows complain it wouldn't bother any of the neighbours.

[Pete "oranges" B.]

Being in The States...

I have always wondered how it would work out strapping one of these to the car and mounting the antenna on the roof.

Better coverage every where you go! Though I don't know how the unit would respond to having the power cut and comeback so often. Some kind of protection circuit maybe?

[Anonymous Coward]

I work for a network operator

You're sweet, go for it.

Merry Xmas!

[Anonymous Coward]

Vodafone?? BAH!!!

The only place in my house that an "Avoidaphone" will work is when you are sat in the bath!!

So I switched back to Orange, GREAT coverage ( for mobile phones, if not internet, their internet service is CARP!!!!).

Mines the "Shower" proof one.

[Francis Vaughan]

Legality

These repeaters are most definately radio transmitters. So they most certainly come under the approriate leglislation. The legislation has a very long history and is pretty severe for a lot of reasons. Essentially, in most countries, unless you have an approriate license you can't operate a radio transmitter. Certain frequency bands have been opened up, and certain certified devices may be operated by ordinary punters in those specific bands, 2.4 GHz is a well known example, but the devices that may be operated must adhere to specific design constraints. Even though 2.4 GHz is available without a license, if you try to fire up a non compliant device in that band you will be quite illegal.

A lot of this legislation is to stop idiots messing things up. And just buying a celluar repeater and installing it could easily involve an idiot messing things up. Whilst the idea seems obvious and easy, the devil is in the details. One of these repeaters could quite easily take a cell down, or at least degrade performance of the cell. For instance the cell handover protocol is rather dependant upon knowing that cells that are not adjacent are not going to try to hand a handset to one another. Willy nilly installation of repeaters could easily violate this assumption, leading to instability in the handover algorithms. Unlikely, especially just boosting signal inside an office space, but quite possible.

The idea that an operator could be involved in the private purchase and instalation is good. But by doing this the operator takes on legal responsibility for any problems that the repeater causes, including interference with other operator's services or any other interference. That is part of what getting a license for a transmitter is about. It isn't just a revenue raiser. It is the licensee warranting that they are competent enough not to mess things up, and taking on legal responsibility for the mess if they do.

[Anonymous Coward]

pay peanuts get monkeys

Having worked at an operator in the department who dealt with this sort of thing I know why some mobile operators don't like them and that's because they use idiots who don't understand how to deploy them. Like putting a microphone in front of a speaker with the volume turned up, lots of noise and lots of dropped calls (money). So if your own staff can't understand how to use them, would you let Joe public loose with one?

[Anonymous Coward]

There are two ends to a stick...

Maybe, just maybe, there may be some of us that welcome poor signal strength during a working day ;)

[Anonymous Coward]

Mobile Provider Approval

Approval from your mobile operator would almost certainly make it legal. You mobile operator holds a licence for that particular frequency, if they were to approve your use of a repeater then you would be covered by their licence.

However, there is a possibility that the use of a repeater could cause interference. It might be a pile of cheap sh*t that causes interference outside it's stated frequency. Even if it is a quality device that operates as it should, it would be hard to tell what effects it may have on the surrounding area without a full survey. Imagine your home is in a dead spot, but homes a short distance away are not. Installing a repeater in your home could potentially cause problems with their reception. Would the solution be for them to install a repeater too? So you can see why mobile operators may be cagey about people installing repeaters without proper planning.

When we were looking into a contract with a new mobile provider we stated that we were concerned that coverage may be poor in some of our buildings. Some of the bidding operators stated that they would install repeaters at no extra charge in any building where we had problems. So the mobile companies have no problems with repeaters, as long as they are the right repeaters and they know about them and their effects.

[Andus McCoatover]

Legal alternative...

May I direct you to the Internet Engineering Task Force's RFC1149 ?

Link at http://tools.ietf.org/html/rfc1149

Data rate a bit slow, but might solve a 'lofty' problem.

[Andus McCoatover]

Repeaters

When I worked at Nokia, we had to do seriously stringent tests on the (GSM) basestations I was involved in designing. European (ETSI) regulations were more stringent than American (ANSI) standards, but I spent many night hours and weekends in an accoustic/EMC measuring room, getting the kit's unwanted - out-of-band- radiation down to acceptable limits. I wanted to acheive ETSI, even tho' the kit was for the Americas' markets

GSM 11.05, 11.21 and 07.01 standards spring to mind, but now it's all under the 3G Partnership Programme - (3gpp)

So, I can't see how a couple of screwed-together fag-packet-sized tin boxes probably made in Taiwan can come close to the requirements.

Bugger me, the standards were strict!