Comreg to investigate car keyfob interference

Altreab

It appears that there is a problem with car Keyfobs in a unnamed housing estate in Dublin. Said keyfobs will not work properly opening the cars remotely in the estate but on exiting the estate (after using the old fashioned method of inserting key in actual cardoor lock to unlock it) drivers are able to drive away with no problem. Thereafter remote working of keyfobs resumes. Cars of all ages and makes are affected.
Above problem was reported on the Gerry Ryan Show at approximately 9:35 this morning ...... He put out a call to the public and various departments to see what the problem could be. By 9:55 a Comreg spokesman had confirmed on air that if they were given the location of the interferance they would have it inspected this afternoon.
Why oh WHY cant they react this fast for anyother problems regarding communications in this country!! Further Updates tomorrow when im sure they will have tracked down the source of the problem

P.S. Wouldnt it be beautiful if it was an Eircon device that was causing the problem? ... then again if thats the case, im sure they would respond by saying that all car makers will now have to change the car keyfobs in Ireland!!

P.P.S ... Another caller rang in and said that he had a similar problem with a motorbike immobiliser when he parked next to a Garda station in a seperate part of Dublin. Orginal Caller had mentioned that there were guards in a house on the estate. Could Garda Signals be causing problems like what happened in the UK with a MOD army base there?

watty

The keyfobs are "licence free" / unlicenced, but CE approved devices. Technically they are not protected from interference of any other CE approved device on same band.

Given difficulties some LICENCED spectrum users have had, I await results with great interest.

bminish

watty wrote:

The keyfobs are "licence free" / unlicenced, but CE approved devices. Technically they are not protected from interference of any other CE approved device on same band.

They are, as license exempt devices, not entitled to protection from the licensed users of that bit of spectrum (who have been around a LOT longer than Car door remotes )

As a license holder for that bit of spectrum (amongst others) I await with great interest any developments.

.brendan

watty

There are a lot of TV video senders that use 433.085Mhz too for IR remote reverse. I wonder how well the receiver survives 400W SSB on that frequency

Altreab

watty wrote:

There are a lot of TV video senders that use 433.085Mhz too for IR remote reverse. I wonder how well the receiver survives 400W SSB on that frequency

I didnt get the full story this morning but it seems to have been a toy connected to a TV using a wireless connection. Comreg confirmed that it was the toy that was causing the problem as when they turned it off keyfobs for 2 affected cars worked, then failed when it was on.
Comreg will be following it up with the suppliers of the toy.

Slutmonkey57b

Right. So someone from Comreg went out to this housing estate and tested this did they? In person! That's what I call service from everyone's most admired civil servants.

aphex™

Slutmonkey57b wrote:

Right. So someone from Comreg went out to this housing estate and tested this did they? In person! That's what I call service from everyone's most admired civil servants.

I'm sure they got one of their contractors to check it out.

Boston

bminish wrote:

They are, as license exempt devices, not entitled to protection from the licensed users of that bit of spectrum (who have been around a LOT longer than Car door remotes )

As a license holder for that bit of spectrum (amongst others) I await with great interest any developments.

.brendan

You seem to be suggesting that licensed operators and unlicensed operators can/do use the same spectrum.

oscarBravo

More accurately, licenced amateurs and (low-powered) unlicenced devices.

aphex™

Well, maybe the car remotes interfered with the toy? Who gets precedence, and why?

watty

There are I think other bands that allow low power "approved" unlicenced / licence free devices in parallel with Licenced operators.

Microwave movement detectors
"iTrips" Band II
Radio Microphones Band III & Band IV/V ?

Then there are bands where different folk have licence at same time:
* Separation by location
* Primary & Secondary user. Secondary user has to accept interence and not cause it (7.1 to 7.2 MHz the secondary users with their 100W mustn't jam the 1MegaWatt jobbies). 10.000GHz to 10.270 and 10.300 to 10.500 has multiple users

10.000 to 10.154GHz has ONLY secondary users, no Primary user!

Of course if you buy thousands of "unlicenced" devices and interfere with a Primary Licenced user it's a bit more sticky than a single dodgy toy taken away for examination.

Then there is all the stuff on Coax (TV modulators, Cable TV, Satellite IF, sky Remote Eye) from 5MHz to 2100MHz that can leak out and cause a huge amount of interference when people insist that their cheap coax works fine for them.

Expensive double screened coax should be a legal minimum. It isn't just so your satellite receiver works, but avoids generating interference or receiving it. A mobile phone can disrupt a satellite channel or vice versa with poor coax.

Then badly designed alarms that are not wireless based at all that "go off" when a phone, licenced taxi/ambulance/police/Amateur etc is nearby. Or HiFi/TVs that pickup radio directely without a tuner.

I'm not impressed with Wire-free Domestic Alarms (433MHz) needless to say. They are too easily deliberately jammed with 30 Euro of device from Hong Kong.

crawler

Slutmonkey57b wrote:

Right. So someone from Comreg went out to this housing estate and tested this did they? In person! That's what I call service from everyone's most admired civil servants.

In fairness to Comreg - if there is a device operating illegally in a frequency band they will go and investigate with spectrum analyzers and remove/turn off etc the offending object - they have to otherwise it makes a mockery of the licensed spectrum schemes and also could be a life and death thing if interference was caused to say something like Air traffic control etc.

watty

If people complain, they do turn up fairly quick.

But current EU and Ofcom spectrum proposals are much more frightning. Someone has beleived the hype surrounding Software Defined Radios. Unfortunately aerials are physical and only work for one frequency and expensive to fit. Physical filters are needed too, which are expensive, not easily changed and not programmable.

Maybe when SDR has 0.01uV to 10V dynamic range and 4000MHz sample rate we can have SDR that don't need filters. Such devices currently aren't even a dream yet. Real SDR that you can buy now or over the next 20 years will need real filters and real aerials. You can't have dynamically assigned / market forces spectrum.

For a start in Ireland it would reduce broadband availablity by nearly 50% as there would be almost no Wireless ISPs. No-one would be able to get return on equipment investment.

watty

aphex&#8482 wrote:

Well, maybe the car remotes interfered with the toy? Who gets precedence, and why?

If both devices are CE marked and approved then neither should have precedence.

However if the Toy has faked CE mark, or is outside legal limits for (licenced or licence free) device etc, all stocks will be impounded.

Boston

watty wrote:

If people complain, they do turn up fairly quick.

But current EU and Ofcom spectrum proposals are much more frightning. Someone has beleived the hype surrounding Software Defined Radios. Unfortunately aerials are physical and only work for one frequency and expensive to fit. Physical filters are needed too, which are expensive, not easily changed and not programmable.

Maybe when SDR has 0.01uV to 10V dynamic range and 4000MHz sample rate we can have SDR that don't need filters. Such devices currently aren't even a dream yet. Real SDR that you can buy now or over the next 20 years will need real filters and real aerials. You can't have dynamically assigned / market forces spectrum.

For a start in Ireland it would reduce broadband availablity by nearly 50% as there would be almost no Wireless ISPs. No-one would be able to get return on equipment investment.

Hey don't knock SDR, its the field I'll be doing my research in next year. Most people look at hardware from a very static point of view, however that is not necessarily the case. Your last statement about dynamically assigned spectrum suggests to me you're talking about cognitive radios. A SDR doesn't have to be cognitive, merely adaptive.

bminish

watty wrote:

If both devices are CE marked and approved then neither should have precedence.

However if the Toy has faked CE mark, or is outside legal limits for (licenced or licence free) device etc, all stocks will be impounded.

ISM in the 433.05 to 434.79 bit of spectrum are generally limited to and ERP of either 1mW or 10mW but subject to a less than 10% Duty Cycle

sounds like something was not working within allowable parameters.

.brendan

fatherdougalmag

Do we know what the toy was? I picked up a Lord of the Rings wireless sword game for my budding Frofo. I didn't have any MIBs knocking on my door.

watty

I have several SDR. I've studied the Black art since ****** . Cognitive radios is another hype / buzz word that means what ever you want.

Humpty Dumpty is alive and well.

But have good fun with the research. The two things that any kind of DSP based approach does well is having any arbitary "Equivalent IF*" bandwidth and any arbitary Modulation / Demodulation scheme. Also noise reduction by signal correlation or removing inband interference duplicated out of band.

But you need a real "front end" or performance is abysmal in the real world.

(* I know many DSP radios use clever Zero IF or direct conversion schemes, but they still have a some kind of bandwidth defined as if it was a real IF filter).

SDR/Cognitive radio can mean nearly whatever you want and is great fun to play with. However while I beleive handing out spectrum should be technology neutral and independent of concepts like Broadcast, Fixed, Data, Video Voice, I think certain kinds of things are best left as they are for a very very long time.
* LF MF HF bands for Broadcast. These can migrate to DRM. But can't chop & Change
* Band II FM. Lets not break it.

* Band III split between DAB and longer range low density Mobile services.

* TV. By all means migrate to DTT. But on a fixed spectrum, with enough for HDTV, but part of existing spectrum (Approx 800MHz to 860) for Mobile Internet. Technology Neutral.

Licences should be long term once a technology is adopted for a particular spectrum slot.

watty

bminish wrote:

ISM in the 433.05 to 434.79 bit of spectrum are generally limited to and ERP of either 1mW or 10mW but subject to a less than 10% Duty Cycle

sounds like something was not working within allowable parameters.

.brendan

A lot of the Video senders use a Super Regenerative Receiver for 433MHz in the 2.4GHz Video TV. These radiate 100% duty cycle. Though i'd assume less than 1mW, but I havn't the gear to measure other than comparative field strength.

bminish

crawler wrote:

In fairness to Comreg - if there is a device operating illegally in a frequency band they will go and investigate with spectrum analyzers and remove/turn off etc the offending object - they have to otherwise it makes a mockery of the licensed spectrum schemes and also could be a life and death thing if interference was caused to say something like Air traffic control etc.

Ho Hum..
I know of an instance of intermittent interference to ATC that did not get tracked down quickly (admittedly intermittent issues are harder to pin down) however the information required to ID the source of the interference was sitting in the public domain on Comreg's web site in the Non-Ionizing reports section.
http://www.comreg.ie/sector/default.asp?stv4=TSG&s=4&navid=179

The first few rounds of Non Ionizing Audit reports included spectrum analyser sweeps
Some sites showed the presence of considerable Spurs and IMD products from Co sited FM broadcast transmitters, Low band PMR etc in the Airband and other bits of spectrum that would have had no license holders on site

I find it suprising that no one in Comreg appears to have payed any attention to these site survey results. basically they mean either (or both) of the following are true

1/ Some sites are Filthy and have a number of engineering issues placing various operators in comprising positions regarding meeting their license conditions.
(Yes some sites are filthy and many shared sites have some issues)

2/ The spectrum analyzer was overloaded in the presence of strong signals and is showing stuff that is not actually there. In this case the entire basis for the accuracy of the NIR report for that site is highly questionable and the consultant tasked with the site survey needs to be asked to do it again with more care.

.brendan

Boston

Watty your a funny guy, I liked you rant, mainly because I understood it. When I say SDR maybe I should say Reconfigurable radio. I'll be looking into FPGA's as a platform, so there will be a real front end. I agree theres allot of buzz and bul**** surrounding this area and even more issues about the actual technolodgy, but sure, I'm not complaining it's going to keep me employed for the next three years.

watty

Don't misunderstand me. I think the technology is great. The traditional RF -> Mixer-> high IF to reject image ->Mixer-> low IF for selectivity --> demodulator all in HW is history. A DSP (SDR or Cognitive) radio is much more fun and flexible. OK you spend more time with PC screen and DSP algorithims than analogue filter design , spice analysis and soldering iron.

Maybe I'l get one of these FPGA evaluationj thingys some are only kind of PC price levels. Cheaper than a mid 1980s In Circuit Emulator or any Year Professional Communications Receiver.

You can play with the ideas cheap too. I got a Softrock V5 7MHz band kit for about 20 Euro. Plugs into sound card but with right software and right sound card you can get 200kHz Spectrum Display and build what ever kind of filters and radio you want in SW.

Of course the more serious stuff uses 12 bit A/D ( or up to 24bit better) convertor running maybe 60MHz samples from an I Q mixer...
Same architecture of SW on PC or FPGA at end of day, difference is the direct frequency and bandwidth and data rate.

Have fun,

bminish

Whilst we are remaining so far off topic!

I have been playing around for the last while with a SDR-14
It's a decent performer, especially when sitting behind a proper Pre-selector.
The windows software is good for monitoring and detailed spectrum analysis but down and dirty signal digging Linrad is the way to go.

There are two other very interesting SDR projects
One is the GNU Radio project along with some versatile hardware http://www.ettus.com/

TAPR are backing the HPSDR project which is a very nice modular approach to a SDR

I think the SDR is here to stay however much of the 'Cognitive' radio is in the same class of wishful but potentially very damaging crap that economists are prone to dream up in 'think tanks' when they get left alone for too long.

.brendan

Solair

You don't have to worry too much about wire free alarms. You can jam them but it will activate the alarm. They constantly scan each sensor and if they don't get a response, they'll detect jamming and an alarm call will go in immediately + the sirons will go off.

They're not as dumb as you might think at first glance

bminish

Solair wrote:

You don't have to worry too much about wire free alarms. You can jam them but it will activate the alarm. They constantly scan each sensor and if they don't get a response, they'll detect jamming and an alarm call will go in immediately + the sirons will go off.

They're not as dumb as you might think at first glance

Now that is Dumb!
One licened user operating entirely within the parameters of his/her license is now likely to trigger all the burglar alarms in the area. Bet these things do not have decent front end filtering on the receivers either.
This type of application really should not be using shared spectrum

.brendan

bushy...

Solair wrote:

You don't have to worry too much about wire free alarms. You can jam them but it will activate the alarm. They constantly scan each sensor and if they don't get a response, they'll detect jamming and an alarm call will go in immediately + the sirons will go off.

They're not as dumb as you might think at first glance

Which leaves them wide open to another type of "attack" ..... keep triggering it and after a while it will be left turned off. The fact its "wire-free" ( wow look what we can do etc) makes it even easier .

watty

Yep you keep doing drive bys till the alarms you noted before don't go off...

I've tested them extensively. They are inherently worthless security against anybody with a few days patience.