Interference between DTT & Mobile services in the UHF bands

The Cush

How will viewers with Group C/D and Wideband aerials (and masthead amps) be effected by the launch of mobile services above Ch 60?

This appears to be of concern to RTÉ/RTÉNL and not to the Dept or Comreg as can be seen from a series of emails between then in the last few months, published recently by Comreg.

RTÉNL says it's a policy issue for Comreg but Comreg says any interference problems are a technical issue for RTÉNL/installers/viewers to resolve.

RTÉNL's Mick Kehoe said the following in an email

RTÉNL stand by its position and at least if/when a problem does arise we will know where to divert the phone calls.

watty

UPC cable will be affected even worse. Tests have proved loss of Broadband and TV when the Mobile Handset is used in the same house.

The so called "digital dividend" is stupidity. The spectrum being offered isn't suitable for 4G Mobile Data at decent speed as the size is too small, Comreg wants 5MHz channels and 4 operators and the range is too great to have smaller cells reliably to increase capacity.

The whole "Digital Dividend" concept was when DTT was imagined to be SD only. No HD or 3D, and also no Satellite or Cable competition.

You can use the 790MHz to 862MHz band for FIXED wireless, as then there are no omni-directional handsets or USB dongles, just an aerial on roof with wireless set feeding a cable modem. The equipment exists off the shelf and is used in several countries. But the Licence process is loaded against such a system. The Fixed Wireless would not interfere with TV or Cable.

The 1800MHz band is badly used.
The 2300MHz band is hardly used.
Big chunks of 872MHz to 1000MHz (containing GSM) are wasted.

The Digital Dividend is 2nd stupid thing since Broadcasting started in 1921, and the 2nd stupidest so far.

So called "White Space", reusing the in Use TV band channels for license-free "outdoor wifi" is the 3rd stupid idea since 1921. It wins the award of being the most stupid and will create FAR more interference than Mobile in the "Digital Dividend" band as the Database scheme can't work reliably.

We are entering an era where Broadcast is no longer protected. Even though the Broadcasters have a licence and the frequencies protected by International Treaty.

The only "right" people have for mains wiring is to get Electricity from it. But Ethernet over Mains and HDMI over Mains are really transmitters now creating interference from 1MHz to 200MHz. Each new generation of "Homeplug" type gadget goes faster and blocks more frequencies.

CE marks are not enforced or policed or properly independently verified so we have PSUs, CFL, chargers etc with filters left out to save cost which make Radio reception from 60Khz up to 20MHz or even weaker VHF-FM stations unusuable.

Sponge Bob

The reason this is of concern is that I understand the interference has started already.

Some high end multiband US LTE Phones have already appeared in Ireland hooting away between 700 and 800mhz and the situation will likely continue to worsen.

Interference with masthead amps can be caused by crap masthead amps, eg wideband ones. I blame the installers for a lot of these, and the same problem was around for some time after Tetra was launched down the bottom end of the UHF band.

Even ole Sponge Bob himself is possibly guilty, must check these in case I nuke a Radio Mike.

Mike 1972

I never thought Id ever hear myself utter these words but......

Surely COMREG are right on this one :eek:

After ASO frequenciess above Ch 60 will be out of band and masthead amps without filtering for these out of band frequencies will be obsolete ?

Its hardly reasonable for broadcasters (and ESPECIALLY cable companies) to demand protection from out of band signals on obsolete or substandard recieving equipment ?

watty wrote: »

since Broadcasting started in 1921..

1921 ???

watty wrote: »

We are entering an era where Broadcast is no longer protected. Even though the Broadcasters have a licence and the frequencies protected by International Treaty..

We have been in that era for quite some time now In most countries AM radio broadcasting has been unprotected for decades (nope that doesnt mean AM pirates are guranteed a free pass though) Its only a matter of time before the (already largely worthless*) protection is withdrawn from FM with the existance of DAB given as an excuse.

* Having being involved in an almost three year campaign to get RTE to clean up spurious signals from one of their FM relay sites. I can attest to this.

watty

Even with really professional filtering and NO mast amp the local handset / Modem dongle is a problem. If there is an attic aerial or indoor aerial the problem is worse.

If ordinary coax is used to connect the TV rather than Satellite grade with foil screen and heavy braid the problem is worse.

I'm not going to explain it here. But even when a transmitter ONLY has transmissions in it's own band it only needs to be about 40dB stronger than a nearby channel to start causing interference.


I said nothing about AM. The fact is that technologies are being allowed that disrupt AM, FM, HF, Mobile, Marine, Aeronautical and HAM. All those are licensed and protected. Any "Amateur" frequencies that are secondary, it's because the PRIMARY licensed user is protected. Besides AM broadcast still does have legal protection in every country by International treaty. Enforcement is a separate issue. Comreg are pathetic at it. They have regularly dragged their feet over Interference issues and also forbidden the victim to say to their customers who the villain was when identified. They are not fit to regulate "White Space" or "Digital Dividend" on their past record of being more interested in collecting Revenue for Dept of Finance. Which is not the stated function of a Communications Regulator. No one ever changed the law or treaties. The problem is Comreg's lack of enforcement. Hence RTE's disquiet about "Digital Dividend". I bet they are in caniptions about "White Space". The problem is Regulators like Ofcom, FCC and Comreg (unilaterally) allowing "Interference", contrary to law.

Only the ISM / Licence free band users have no protection. (CB, 49MHz, 433MHz, 446MHz, 864MHz, 2.4GHz, 5.8GHz)

NewHillel

Firstly, I agree with the COMREG position.

However, the correspondence published, shows the value of a professional aerial installation, by competent installers, with the right equipment.

This is an area where the ISAA could really shine, without any of the 'Rogue Installer' $hite.

Why not offer real
consumer protection, in two critical areas:

1. A financial guarantee on the quality of the installation, to a certain financial limit, say €300. (The CAI already do this,at least in the UK.)

2. A guarantee that any future interference issues will be resolved, or the installation cost refunded, for a 5 year period.

These are real differentiators that couldn't easily be matched by untrained or badly equipped installers.

Think about it, it would provide a real basis for an ISAA campaign, along the lines of 'Why you should choose an ISAA installer. (Put it this way, I wouldn't even bother doing work for myself, as I couldn't be bothered sourcing the necessary filters, etc., required.)

The ISAA could negotiate suitable insurance cover, for itself and members, to mitigate the financial risk.

Mike 1972

watty wrote: »

I'm not going to explain it here. But even when a transmitter ONLY has transmissions in it's own band it only needs to be about 40dB stronger than a nearby channel to start causing interference.

Im not suggesting reciever generated interference from out of band transmissions wont be a problem but is it an issue that COMREG should concern theselves with given that the onus in such cases is on the user of the reciever to resolve such issues ? International treaties concern themselves with in band signals and transmitter generated spurious emissions.

As any RF transmitter can potentially interference on inadequetly designed or screened recieving installations on widely differing frequency ranges any proposal that restrictions be imposed on such transmissions would be patently unworkable besides given that COMREG are unwilling/incapable of resolving most of the in-band interference which arises legislating for out of band issues would be rather pointless.

Im with you on the PLT/White Space/General EMC stuf though !

watty

Actually guard bands exist between different type services by International Agreement. These have to take account of:

• The typical location of Transmitter
• Type of modulation and level of out of band signal due to that
• Existing neighbour band equipment.

Harmonics of transmitters and spurious signals from Transmitter IF and L.O. harmonics on both sides of carrier are not really a problem on Modern systems. The points above are serious issues.

Even if the Receiver generates NO interference the filters will not block a local transmitter 100dB more than desired RF, only 20MHz away. It's not feasible in consumer gear. Though it's a huge problem for UPC as someone using a Tablet or phone is actually ON the Cable TV digital TV or Modem frequency at 100dB more power than Three Rock at same location. In Sth. Dublin the Analogue, DTT and DAB all interfere with cable to some extent. A nearby "Digital Dividend" Handset/Modem could be over 100dB more. The Masts are a tiny problem in comparison.


The Guard band size for "Digital Dividend" is designed unfortunately only taking the Base or Mast transmitter into account. It would be fine for Fixed Wireless. However Mobile Handsets and USB dongles and Tablets etc are likely to be used indoors. These are largely the interference problem. Though there are problems with mast Amps or larger aerials in line with a Mobile Mast. Even GSM can be a problem today on higher channels UHF if the TX is far off and a nearby mobile mast. But it's rare. GSM Mast TX frequencies are upward from about 925MHz. Top UHF TV is 862MHz.

But my argument is deeper. I do not believe this is driven by consumer need, nor required. It's just a way for Mobile operators to build giant cells with x3 fewer to x9 fewer masts (and consequent 1/3rd to 1/9th data cap or user numbers) for Rural locations. It will forever sacrifice TV band in exchange for "Midband" Mobile Data that just saves some Capex to foreign operators. It will not benefit Broadband use or local Wireless ISPs.

The so called "Digital Dividend" should be scrapped in all of Europe and the space reserved for HDTV, 3D TV, real 3D TV etc... There is plenty of other more suitable Spectrum for Mobile and Fixed Wireless. No shortage if it used efficently.

The reality is the "Digital Dividend" is not to benefit the Consumer at all, but Government coffers by sell of of spectrum to highest bidders. It's 100% driven by selfish "Depts of Finance", no other reason.

If they insist on the Stupid "cash grab" of "Digital Dividend" there is a solution. Licence should be for outdoor greater than 9dBd gain fixed aerials at chimney height only, fixed wireless. The contention should be limited to 20:1 by sufficient channels and base stations and the peak time speed no less that 90% of package speed, which should be a minimum of 2Mbps up and 16Mbps down. That would be real Broadband with range up to 40km with suitable aerials. The Technology has existed off the shelf for over 8 years.

It's Wireless DOSCIS, UPC's Cable Broadband over Wireless. It's what the Digiweb Metro uses (much more expensive band and only Line Of Sight 10km range as it's 10,600MHz not 800MHz).

Rural LTE or Mobile WiMax on 800MHz with the 4 operators and 5MHz Comreg envisage could actually be poorer than 3G in many locations. To get decent speed the LTE needs a single "RAN" operator in a band and at least 6 x 20MHz channels in both directions (up and down). That would need the Entire existing GSM band, some other bits and a slightly extended "Digital Dividend" band to have 240MHz with duplex guard in the middle and Guard at top and bottom end. The existing Licence Free unprotected 864MHz to 868MHz gadgets, walkie talkies and cordless barcode terminals can live in the duplex guard band.

But the current proposal essentially tailored to raise maximum revenue from Mobile operators (no way can Fixed Wireless ISPs compete) is a disaster for all of Europe.

Antenna

watty wrote: »

In Sth. Dublin the Analogue, DTT and DAB all interfere with cable to some extent.

There were no problems with DTT affecting cable in Dublin as it is above both analogue and digital cable in frequency there - though it did happen in Waterford city when the new transmitter for DTT there did clash with analogue cable in the low end of the UHF band.
http://www.boards.ie/vbulletin/showthread.php?t=2055767531
The solution was for UPC to duplicate the affected on another channel and get viewers to retune. Was big problem due to the close proximity of the transmitter to cabled areas!

However Dublin has DAB affecting BBC2 TV on UPC analogue cable where areas with a strong DAB signal + cable pickup/ingress a problem, posted here many times in the past.

watty

It does interfere, reducing SNR on digital carriers used for DOCSIS (Broadband) and Digital TV. But if the interference is below low enough for the FEC and SNR (BER), the user is not affected. LTE will interfere enough to affect it from User perspective.

Without Spectrum analysers and meters that display BER, it's not possible for users to see serious interference that is just below the threshold.

Antenna wrote: »

However Dublin has DAB affecting BBC2 TV on UPC analogue cable where areas with a strong DAB signal + cable pickup/ingress a problem, posted here many times in the past.

A local "digital dividend" handset / Modem upload channel will be maybe 100dB more than DAB.

Also it's normal on all Mobile systems and many fixed systems for the uplink (handset/modem) to transmit on the lower half of the band, then an empty duplex guard and then the Mast downlink transmits on top half of band. Unfortunately that is the worst way round for co-existence with DTT or Cable.

An aside
Digiweb Metro is one the few reverse systems, the downlink is 10.2GHz, uplink 10.6GHz roughly (most systems the uplink is lower band). It's DOCSIS like UPC, DOCSIS can use any channel between 110MHz and 862MHz, or even maybe 1.2GHz (Channels are from 2MHz wide to 10MHz wide, but 6MHz USA and 8MHZ Europe are the common sizes)on some for downlink with the uplink using 0.8, 1.6, 3.2 or 6.4MHz channel between 5MHz and 65MHz. UPC channels between 110MHz and 862MHz are 8MHz and can each be a DVB-C "multiplex", DOCSIS downlink or one Analogue channel. Since the Analogue channels came first they use the lower frequencies as the cable network originally was upto 450MHz, then 560MHz and now 862MHz, or exceptionally in some Countries now 1200MHz (1.2GHz). As cable is converted to HFC with fibre fed cabinets many networks can expand to 1.2GHz to have 100Mbps data at low contention, VOD, Switched video and HDTV.
So the outdoor Wireless set uses a single L.O. at about 9.7GHz to convert the 10.2GHz to 485MHz approx (in cable modem downlink band) and the Modem 21MHz uplink converted to 821MHz and then same L.O. as for receive added to give the 10.6GHz approx uplink. I suspect the choice of frequencies is to reduce cost. The Metro outdoor unit is 1/6th of cost of previous non-DOCSIS 10GHz links and about 1/5th cost of current alternate 10GHz links. The coax carries +12V power and identical signals as a UPC modem would use.

NewHillel

watty wrote: »

It does interfere, reducing SNR on digital carriers used for DOCSIS (Broadband) and Digital TV. But if the interference is below low enough for the FEC and SNR (BER), the user is not affected. LTE will interfere enough to affect it from User perspective.

Without Spectrum analysers and meters that display BER, it's not possible for users to see serious interference that is just below the threshold.

Hence my suggestion that this is a real opportunity for the ISAA. Surely, one of the means of minimising this concern, and future-proofing installations, is to have adequate shielding with the option of suitable filters, if subsequently required? (I'm not referring to 'cable' installations, here.)

Only a small number of installers need have a deep understanding of problematic interference identification and mitigation and the more sophisticated equipment needed for same, similar to 2nd level support. This could then be available to all installers.

watty

NewHillel wrote: »

Hence my suggestion that this is a real opportunity for the ISAA.
....
small number of installers need have a deep understanding of problematic interference identification and mitigation and the more sophisticated equipment needed for same, similar to 2nd level support. This could then be available to all installers.

Decent filters that make a difference are very expensive. Also they will only help with interference received by aerial on roof. The major problem with "digital dividend" be local modem dongle/handset getting picked up by TV, Set-box, coax or RF patch cord directly. Nothing can mitigate that.

ISAA and professional installers have always recommended TX100 / PF100 / CT100 type foil + heavy screen satellite cables, not the cobweb screen stuff installed by most builders and sold in many retail shop. UPC believes in "RG6" but you'll find that professional cable makers make many types/grades of "RG6"-something varying from Aluminium metallised plastic for screen foil, with loose aluminium braid and copper plated steel inner core wire (cheapest and to be avoided) to an "RG6"-something-else with dense copper braid you can't see through, solid copper foil and solid copper inner core wire, with identical spec to PF100. So "RG6" on its own isn't a useful spec.


Yes, from the beginning I suggested that ISAA set up a technical support panel with gear, and also gear available to hire for those qualified to use it (at a price to cover wear & tear and upgrades). This would be one of the benefits of membership. It was never ever envisaged as a "bulk purchasing club" or "trade cartel" like some groups are (I'm NOT thinking of anyone in particular, OK?).

NewHillel

watty wrote: »

Decent filters that make a difference are very expensive. Also they will only help with interference received by aerial on roof. The major problem with "digital dividend" be local modem dongle/handset getting picked up by TV, Set-box, coax or RF patch cord directly. Nothing can mitigate that.

ISAA and professional installers have always recommended TX100 / PF100 / CT100 type foil + heavy screen satellite cables, not the cobweb screen stuff installed by most builders and sold in many retail shop. UPC believes in "RG6" but you'll find that professional cable makers make many types/grades of "RG6"-something varying from Aluminium metallised plastic for screen foil, with loose aluminium braid and copper plated steel inner core wire (cheapest and to be avoided) to an "RG6"-something-else with dense copper braid you can't see through, solid copper foil and solid copper inner core wire, with identical spec to PF100. So "RG6" on its own isn't a useful spec.


Yes, from the beginning I suggested that ISAA set up a technical support panel with gear, and also gear available to hire for those qualified to use it (at a price to cover wear & tear and upgrades). This would be one of the benefits of membership. It was never ever envisaged as a "bulk purchasing club" or "trade cartel" like some groups are (I'm NOT thinking of anyone in particular, OK?).

I agree with most of the above, I do believe that a fully shielded termination, all the way to the TV, would mitigate in-Home generated interence, also. With the proposed installation inspections the ISSA should really stand out from the crowd.

(PS, There is evidence to suggest that Operators are starting to move way from Homeplug solutions, due to interference issues.)

watty

BT's own DSL people told BT Vision people not to do it, at the beginning! On occasion "Homeplug" blocks DSL or causes it to sync at much much lower speed. I'd guess when there are runs of phone and mains side by side, or outdoor overhead phone cable picking up the lights wiring. Often lights are wired with Live and negative separate cables to loop between fittings, switches etc and thus the lighting circuits make great loop aerials for Homeplug and other high speed signalling over mains solutions.

watty

NewHillel wrote: »

I do believe that a fully shielded termination, all the way to the TV, would mitigate in-Home generated interence, also.

Sadly I have found that it doesn't work as the boxes / TVs are not shielded and also may use unshielded poor design of PC track or such. Also viewers will add a box and use cheap RF patch cable.

The Belling lee connectors are rubbish design that isn't even 75 Ohms. Proper quality F-Connectors are better. Badly fitted screw on types can be worse.

I've even seen PC mice affected by 0.5W RF and systems fall over due to RF pickup on the speaker cables.

It was easier to add a filter on old Record Players to stop them picking up Taxis and Police in the "old days" than sort EMI "retro fit" problems on some modern gear.

The number of Plug Top PSUs even I've had to scrap as there was no filtering (and yet they had CE marks, no way would they have passed).

The Regulator is not doing their job. The CE mark system is broken as it's not pro-actively policed or independently verified.

This the environment Comreg wants to unleash licence Free "White Space" and also Mobile use of the "Digital Dividend" band.

I'd only just support the "Digital Dividend" if the Regulator showed competence and wrote the licence conditions to limit it only to "Fixed Wireless". It's impossible to mitigate Mobile Interference on such nearby band.

They want "White Space" in similar time scale. Madness.

NewHillel

watty wrote: »

Sadly I have found that it doesn't work as the boxes / TVs are not shielded and also may use unshielded poor design of PC track or such. Also viewers will add a box and use cheap RF patch cable.

The Belling lee connectors are rubbish design that isn't even 75 Ohms. Proper quality F-Connectors are better. Badly fitted screw on types can be worse.

I agree that the Belling Lee connectors are rubbish, but the ISAA. Could standardise on F Connectors, with a suitable adapter for the TV. The additional cost, when bought in bulk, is not much.

Crimp F connectors can also be badly fitted, and be equally bad. It really comes down to proper tools, proper materials and training.

The Conformance Testing is an entirely different matter. I suspect we are close in our thinking.

watty

NewHillel wrote: »

I agree that the Belling Lee connectors are rubbish, but the ISAA. Could standardise on F Connectors, with a suitable adapter for the TV. The additional cost, when bought in bulk, is not much.

I've tried that. Sadly the Belling Lee Socket isn't 75 Ohms either. If you have mis-match even a double screened coax radiates and picks up. On UHF repeaters I've used ferrite clamps + cable loop as UHF balun/current mode choke and third screen earthed only at the radio end to get good isolation. That was on systems with BNCs. With good isolation I was able to get 300m range with the transmitter at 100mW direct into a 50 Ohm BNC dummy load. Normal aerial on the Repeater. Audio on the 8W UHF transmitter and 5W VHF transmitter driven from the UHF receiver. All in one case with a single dual band VHF/UHF aerial. That kind of engineering isn't plausible on domestic systems. I had to UHF filter all the power and audio cables and isolate the metal cases of the three radios from metal chassis!


I've also tested domestic gear with a screened 75 Ohm dummy load on input and it's amazing how much is still received!

FREETV

watty wrote: »

UPC cable will be affected even worse. Tests have proved loss of Broadband and TV when the Mobile Handset is used in the same house.

The so called "digital dividend" is stupidity. The spectrum being offered isn't suitable for 4G Mobile Data at decent speed as the size is too small, Comreg wants 5MHz channels and 4 operators and the range is too great to have smaller cells reliably to increase capacity.

The whole "Digital Dividend" concept was when DTT was imagined to be SD only. No HD or 3D, and also no Satellite or Cable competition.

You can use the 790MHz to 862MHz band for FIXED wireless, as then there are no omni-directional handsets or USB dongles, just an aerial on roof with wireless set feeding a cable modem. The equipment exists off the shelf and is used in several countries. But the Licence process is loaded against such a system. The Fixed Wireless would not interfere with TV or Cable.

The 1800MHz band is badly used.
The 2300MHz band is hardly used.
Big chunks of 872MHz to 1000MHz (containing GSM) are wasted.

The Digital Dividend is 2nd stupid thing since Broadcasting started in 1921, and the 2nd stupidest so far.

So called "White Space", reusing the in Use TV band channels for license-free "outdoor wifi" is the 3rd stupid idea since 1921. It wins the award of being the most stupid and will create FAR more interference than Mobile in the "Digital Dividend" band as the Database scheme can't work reliably.

We are entering an era where Broadcast is no longer protected. Even though the Broadcasters have a licence and the frequencies protected by International Treaty.

The only "right" people have for mains wiring is to get Electricity from it. But Ethernet over Mains and HDMI over Mains are really transmitters now creating interference from 1MHz to 200MHz. Each new generation of "Homeplug" type gadget goes faster and blocks more frequencies.

CE marks are not enforced or policed or properly independently verified so we have PSUs, CFL, chargers etc with filters left out to save cost which make Radio reception from 60Khz up to 20MHz or even weaker VHF-FM stations unusuable.

Watty did you air your grievance to RTE and Comreg about the stupidity of the digital Dividend? Surely as you know what you are talking about from a technical point of view that they will realise you are correct when it applies to the new technology of 4G?

watty

It's nothing to do with RTE, they would be happy to keep 790MHz to 862MHz as it's likely the future of Broadcasting needs the Spectrum.

TV3, TG3, RTE and RTENL get NOTHING from the "Digital Dividend".

Comreg listen only to their "peers" in Ofcom and FCC etc. I've met them face to face. There are good Engineers there. The Policy setting managers don't listen to them.

I've been at Comreg sponsored Conference on it and spoken to OECD attendees too.

In the past I've worked with Communications & Telecomms Engineers from USA, Switzerland, Czech Republic, Netherlands, Slovakia, Ireland, Israel, Hong Kong and South Africa.

There is a collective madness in Regulator circles and unwillingness to tackle Gadget makers and unbelievable and illogical belief in Mobile and Satellite Technologies. The Irish Government is at the forefront of the lunacy with the NBS.

Irish NBS (National Broadband Scheme) customers are ineligible to join the "Sam knows" white box scheme funded by EU to measure Broadband quality as it doesn't meet the minimum criteria for Broadband!

Nor are Satellite Terminal users eligible.

Comreg and Government are convinced the Digital Dividend is worth €250M to €500M, it's not unless the Mobile Operators are stupid. The entire value is predicated purely on the theory that there will be 4 Mobile operators in 30MHz + 30MHz roughly of spectrum delivering "Broadband". Sheer baloney. Maybe with Fixed Wireless, it's only just possible. certainly not with Mobile. Even with 120 + 120MHz of spectrum LTE might only just do entry level broadband. If there was enough base stations. But only in the very most rural areas is the minimum cell size appropriate to 800MHz band small enough. That could be better served with LTE on 1800MHz which is under used by the GSM operators.

Also 2.3GHz (2,300MHz) is held by Eircom and virtually unused for years. They are NOT a state company. By LAW they should have lost the spectrum (principle is you are forbidden to "sit" on Spectrum).

lucernarian

On a practical note I find it hard to get good quality amps that have f-connector inputs, are screened and also are grouped. In any case, there's very little that can be done until aerials and amps are finally manufactured to not specifically receive 800MHz broadcasts. I.e. Group C/D aerials and combiners etc. no longer tuned specifically to work from Ch. 61 to 69.

The Cush

To_be_confirmed wrote: »

In any case, there's very little that can be done until aerials and amps are finally manufactured to not specifically receive 800MHz broadcasts. I.e. Group C/D aerials and combiners etc. no longer tuned specifically to work from Ch. 61 to 69.

With the top end of the band lost from broadcasting throughout Europe I wonder if aerial manufacturers have plans to revise existing aerial grouping or introduce new aerial groups in the coming years, add to that a potential loss of another slice of spectrum to Digital Dividend 2 in the next 10-13 years.

watty

A second so called "Digital Dividend" may not happen. That was planned before HD and 3D.

Also if the Mobile operators have any wit they will not bid silly prices on the first one.

The Cush

watty wrote: »

A second so called "Digital Dividend" may not happen. That was planned before HD and 3D.

Digital Dividend 2 is only being planned now.

The push is coming from countries in the eastern part of Europe where Digital Dividend 1 is not fully available due to their border with Russia who I believe do not plan to release this spectrum in harmonisation with the EU.

Finland started the ball rolling in 2010. It's down for discussion at WRC2012. Legislation making its way in Europe requires a further 1200MHz of spectrum to be identified for release by 2015 which would include Ch 49-60.

Comreg plan to consult on DD2 in the middle of the year and this is what the Dept says

As 2020 approaches there will be pressure for a second digital dividend before 2025. It may even be that the TV services will loose spectrum above 694MHz by 2020. This would mean that channels 49-60 would cease to be available for DTT.

It may not happen or they may allocate a smaller slice under pressure for broadcasters etc., who knows what will happen in the next 13 years.

Sponge Bob

The Cush wrote: »

It may not happen or they may allocate a smaller slice under pressure for broadcasters etc., who knows what will happen in the next 13 years.

I have been saying we should release 700mhz+ for a DD2 for years around here.

The Finns suggest making Mobile and TV EQUAL Primary users across the entire 470-790mhz band. I think this is mad. I would allow countries to decide which of TV or Mobile is the primary user from 694mhz to 790mhz and subject to Co Ordination with a neighbour who chooses to continue to use 694-790mhz for TV as now.

Officially since WRC 2007 the Digi Divvy band from 790-864mhz is a Co Primary user with Mobile and TV is still allowed in that band but the EU has told TV to bugger off out of there by ASO time.

I do not support a blanket Primary user protection for TV between 694 and 790mhz. What about a country with only 2 TV channels and them both crap. They don't need a full 320mhz blocked off do they, they could use 50 mhz and an SFN and have plenty of wiggle room. Even without an SFN they would probably be able to do it.

So Co Primary only per country and after co - ordination and subject to the rights of neighbouring countries to remain as is. If Ireland wants the UK out of 694mhz to 790mhz...in Wales and NI...... we must pay for the work involved IN THE UK out of our spectrum licence fees...and then only if the UK agree to move in the first place.

watty

I'd support that, but ONLY if the entirety of 700MHz to 960MHz is fixed Wireless.

the 700MHz to 790MHz is pointless for Mobile.

Actually we should have Oireachtas TV as well as the other Four channels (the RTE News Now, RTE+1 and RTEjr are not real channels). We may have 7 or 8 rubbish channels, but that's no excuse to Cripple Broadcast forever to have more "midband" services.

But if the existing channels and Oireachtas TV are to be HD and maybe 3D content the 700MHz to 790MHz is needed.

It's short sighted to flog off Broadcast Spectrum for Mobile services that will be no better than existing ones, when in reality there is no genuine spectrum shortage. The Digital Dividend isn't needed.

More intelligent use of all the Mobile bands from 872MHz to 2300MHz is needed. The 2.5GHz could be fixed or Mobile.
Mobile Nomadic on 3.6GHz should be illegal and it should be fixed only.

watty

SFN have lots of limitations. You can't do them everywhere. The delay between signals arriving can't exceed the symbol guard time. They were over hyped.

reslfj

Sponge Bob wrote: »

I have been saying we should release 700mhz+ for a DD2 for years around here.

That doesn't necessarily make it a good idea - does it?

Sponge Bob wrote: »

... They don't need a full 320mhz blocked off do they, they could use 50 mhz and an SFN and have plenty of wiggle room.

The ROI cannot use all channels - they must be shared with NI and the rest of the UK. The UK will have an even bigger sharing problem with NL, BE and FR. SFN is not a fix for all spectrum problems. Some bit-rate is also lost using SFN's due to the needed guard and the PP (pilot pattern) used.

watty wrote: »

SFN have lots of limitations. You can't do them everywhere. The delay between signals arriving can't exceed the symbol guard time. They were over hyped.

DVB-T SFN's does work nicely in most places within areas of 60-100 km in diameter. But ín addition to limits in signal arrival delays, large country-wide SFN's will often suffer from problems with network self-interference.
This is the sum of all signals received from SFN TX sites arriving outside the guard time. Each a very small signal level, but the sum of the many interference signals can be larger than allowed for reception of the multiplex.

Lars

The Cush

The Cush wrote: »

How will viewers with Group C/D and Wideband aerials (and masthead amps) be effected by the launch of mobile services above Ch 60?

This appears to be of concern to RTÉ/RTÉNL and not to the Dept or Comreg as can be seen from a series of emails between then in the last few months, published recently by Comreg.

RTÉNL says it's a policy issue for Comreg but Comreg says any interference problems are a technical issue for RTÉNL/installers/viewers to resolve.

RTÉNL have now added the following caveat to the RTÉNL -Saorview FAQ regarding aerial installations that could be subject to interference from future non-broadcast services above UHF Ch 60.

Some existing aerials, that work fine now, may require filtering at some time in the future as other, non broadcast, services move into adjacent frequency bands.

http://www.rtenl.ie/wp-content/uploads/2012/01/RTÉNL-SAORVIEW-FAQs-Jan-2012-Rev-6.0.pdf, page 13

This warning is highlighted 5 times in the FAQ

The spectrum used for wireless services is becoming more and more congested. This includes the radio spectrum used for television broadcasting which is reducing. As different services are moving closer and closer together cross service interference becomes more of an issue. If you are doing work, or having work done on your television aerial, RTÉNL recommend that you ensure that the aerial is restricted, in so far as is possible, to the television broadcast band only (UHF channel 21 to 60). To protect your television services against interference into the future frequencies / channels above and below this should be filtered out.

http://www.rtenl.ie/wp-content/uploads/2012/01/RTÉNL-SAORVIEW-FAQs-Jan-2012-Rev-6.0.pdf, pages 13,21,22,23,31

The Saorview - Your Aerial page hasn't been updated with the above information yet

There are a number of simple tests to help you determine if your aerial will receive the SAORVIEW signal:

1. If you currently receive TV3 as an analogue service through your aerial then your aerial is most likely fine and is pointing in the right direction. You should not need to do anything with your aerial.

The Cush

Information has now been added to the Dept of Communications website on interference to TV services from mobile services. A link to an LTE/GSM rejection filter is also included.

Spectrum Policies and the Digital Dividend

Spectrum Policies

The successful delivery of spectrum policies and the realisation of their potential is important for the Department, and involves balancing the competing demands of different, though converging, sectors. Priorities must be determined and a way forward identified while recognising that there could be competing cross departmental sector policies that need to be taken into account, as spectrum is a major and critical enabler for the different sector developments.

The Digital Dividend is regularly referred to when the radio spectrum is being discussed. It is the spectrum that will be released following the migration of terrestrial television broadcasting from the traditional analogue transmission to digital transmission. This will occur in the UHF band in Ireland after 2012.

Whilst the Irish TV services are now available by Digital TV to most of the country, since the number of services carried on Digital Terrestrial Television is less than had been anticpated, it will be possible to introduce other services into digital dividend sooner than had been anticpated.

As the manager of our spectrum resource, ComReg has a major role to play in ensuring that the success of this process is realised. ComReg have recently indicated (ComReg 10/59) that they intend to bundle the digital dividend spectrum with the existing 900MHz cellular telephony spectrum in a future compeition.

In order to ensure compatiblity (see EBU article) between the new "LTE" mobile telephony systems (on frequencies previously used for analogue TV) and the Digital Terrestrial Television system, it is likely that some viewers will have to have a filter installed to reduced the strength of the cellular signal at their TV or Set Top Box. Typical filters are being tested by ComReg. Such filters may be needed in cases where the DTT signals are above channel 51 and in particular in cases where channel 58 (770MHz) or 59 (778MHz) are to be used by DTT. That is installations using the "group C/D" type aerial.

Installations (for reception of Saorview DTT above channel 51) in areas at the edge of a DTT transmitter service area or which use a mast head amplifier will most likely need a filter. This is because mast head amplifiers are prone to an "overload" condition if the signal level from either DTT or other sources is very strong. Mast head amplifiers should ideally only be used where necessary for reception of DTT. Excessive amplification of a DTT signal can cause set top boxes to appear not to be able to decode the DTT service.

The Saorview coverage checker can be used to indicate whether the DTT transmissions serving an area are likely to be in channel 51 or higher.

There is a lot to be done between now and the cessation of analogue television services in the UHF band. The Department will fully engage with ComReg and the other stakeholders involved in order to deliver the best results for Ireland.

Last Updated:30/01/2012

http://www.dcenr.gov.ie/Communications/Business+and+Technology/Digital+Dividend/

The Cush

The Cush wrote: »

Information has now been added to the Dept of Communications website on interference to TV services from mobile services. A link to an LTE/GSM rejection filter is also included.

Webpage updated 7th Feb

Spectrum Policies and the Digital Dividend

Spectrum Policies

The successful delivery of spectrum policies and the realisation of their potential is important for the Department, and involves balancing the competing demands of different, though converging, sectors. Priorities must be determined and a way forward identified while recognising that there could be competing cross departmental sector policies that need to be taken into account, as spectrum is a major and critical enabler for the different sector developments.

The Digital Dividend is regularly referred to when the radio spectrum is being discussed. It is the spectrum (790-862MHz) that will be released following the migration of terrestrial television broadcasting from the traditional analogue transmission to digital transmission. This will occur in the UHF band in Ireland after 2012.

Whilst the Irish TV services are now available by Digital TV to most of the country, since the number of services carried on Digital Terrestrial Television is less than had been anticipated, it will be possible to introduce other services into digital dividend sooner than had been anticipated.

As the manager of our spectrum resource, ComReg has a major role to play in ensuring that the success of this process is realised. ComReg has recently indicated (ComReg 10/59) that it intends to bundle the digital dividend spectrum with the existing 900MHz cellular telephony spectrum in a future competition.

In order to ensure compatiblity (see EBU article) between the new "LTE" mobile telephony systems (on frequencies previously used for analogue TV) and the Digital Terrestrial Television system, it is likely that some viewers will have to have a filter installed to reduced the strength of the cellular signal at their TV or Set Top Box.

Filters may be needed in cases where the DTT signals are above channel 51 (due to potential so called image channel “N+9” sensitivity of some receivers) and in cases where channel 58 (770MHz) or 59 (778MHz) are to be used by DTT. That is installations using the "group C/D" type aerial. It is stressed that difficulties may only arise at locations close to LTE base stations. Typical filters are being tested by ComReg, though for reception of channel 59 the filter will need to provide signal reductions above 790MHz whilst having a low loss in ch 59 (778MHz). ComReg has planned that ch 60 (786MHz) will not need to be used by the DTT services for which they are required to make spectrum available.

The Saorview coverage checker can be used to indicate whether the DTT transmissions serving an area are likely to be in channel 51 or higher.


Mast Head Amplifiers

Installations which use a mast head amplifier for TV reception (irrespective of the frequencies to be received) will most likely need a filter. This is because mast head amplifiers are prone to an "overload" condition if the signal level from either DTT or other sources (on frequencies either above or below the TV signal) is very strong. In these overload conditions unintended signals called “intermodulation products” can be radiated causing interference to other users of the spectrum.

Mast head amplifiers should only be used for reception of DTT where there is a clear need to do so. Excessive amplification of a DTT signal can cause set top boxes to appear not to be able to decode the DTT service.

There is a lot to be done between now and the cessation of analogue television services in the UHF band. The Department will fully engage with ComReg and the other stakeholders involved in order to deliver the best results for Ireland.

Last Updated:07/02/2012

http://www.dcenr.gov.ie/Communications/Business+and+Technology/Digital+Dividend/

Ronnie Raygun

This is a good read, even taking into account the fact the UK have far more low powered relays.

zg3409

From:

http://www.bbc.co.uk/news/technology-17125468

4G TV interference: Up to a million homes 'need filters'
The 4G signal will be used by the next generation of smartphones and tablets Continue reading the main story
Related Stories
Ofcom extends 4G coverage plans
Will 4G be faster than home broadband?
Almost a million UK homes will need to have filters installed to prevent TV interference from 4G mobile signals - at a cost of £108m.

A smaller number of homes - about 10,000 - will need to switch to satellite or cable TV services in order to avoid degraded picture quality.

Homes that cannot receive these alternative platforms will receive up to £10,000 each to "find a solution".

Costs will be met by the winner of a spectrum auction later this year.

Consultations are currently being held into how spectrum - which is used by analogue television - will be offered to mobile operators once airwaves are freed up by the switch to digital.

These airwaves are crucial to mobile operators to create next-generation mobile services.

The winning bidder, or bidders, will be required to pay for the costs of making sure viewers of digital terrestrial television (DTT) will not be affected by the changes.

Unwanted noise

In a consultation document released in August last year, media regulator Ofcom estimated that about 760,000 homes could be affected.

However, the Department for Culture, Media and Sport (DCMS) told the BBC that further research had suggested that number was likely to be closer to 900,000.

Homes falling within a certain range of transmitter towers will automatically have a filter issued, while a helpline will be set up to deal with interference cases outside of the predicted areas.

The filter, which is fitted to a digital TV box, blocks out unwanted noise from the 4G signal.

Continue reading the main story
“
Start Quote
If you give £10,000 to a lady in Cumbria and say: 'You need to fix it' - I don't think it's enough”
End Quote
Saverio Romeo

Industry analyst
It can be fitted without the help of an engineer - but over-75s and disabled people will be given assistance if needed.

The DCMS said that in a very small number of homes, the filters would not be sufficient. A platform change - to satellite or cable - will be required, the cost of which will also be covered by the mobile operator.

It is estimated that about 10,000 homes may need to take this measure.

It is also predicted that about 500 homes affected by interference will be unable to receive satellite or cable services.

In these cases, expected to be in rural areas, up to £10,000 per household will be provided to fund alternative solutions to receiving television - such as having fibre cabling installed.

The DCMS said it predicted that small groups of affected houses would be able to pool their funding in order to pay for bigger investments like additional relay transmitters.

'Disruptive'

Without the preventative measures, television picture would become unclear and fragmented, warned Saverio Romeo, an industry analyst from Frost & Sullivan.

"The LTE [Long Term Evolution] spectrum, particularly on 800Mhz, overlaps part of the DTT spectrum," he said.


Culture Minister Ed Vaizey said 4G technology would give the UK an economic boost "The closer you are to a base station, the more disruptive the interference."

He said that in addition to the £10,000 fund for the severely disrupted homes, education should be provided in order to help people understand what options were available.

"If you give £10,000 to a lady in Cumbria and say: 'You need to fix it' - I don't think it's enough.

"You need to help people understand new technologies. It's not enough to give subsidies."

A spokesman for the DCMS said additional advice would be given to those receiving the financial help.

Culture Minister Ed Vaizey said adoption of 4G would provide a boost to the UK's digital economy.

"Next-generation mobile services are essential for economic growth. They will bring an estimated benefit of £2-3bn to the UK economy.

"There will be some interference when 4G services are rolled out but we will have the solutions in place to eliminate the disruption to television viewers."

The Cush

The Cush wrote: »

With the top end of the band lost from broadcasting throughout Europe I wonder if aerial manufacturers have plans to revise existing aerial grouping or introduce new aerial groups in the coming years, add to that a potential loss of another slice of spectrum to Digital Dividend 2 in the next 10-13 years.

Article from this month's What Satellite & Digital TV magazine (#315, Summer2012)

At a recent CAI seminar they outlined proposals for new revised aerial groups.

- The 3 main aerial groups A, B, C/D would be reduced to 2 groups L, H.
- Aerial groups K, E would disappear
- The wideband group W would be replaced with a reduced wideband (21-60) group T (Triax has 4 "reduced-band" wideband aerials in its 2012 catalogue)

Existing Aerial Groups
Group|Channels| Bandwidth| Colour| Code
A |21 – 37| 470 – 606 MHz| █ |Red
B| 35 – 53| 582 – 734 MHz| █ |Yellow
C/D| 48 – 68| 686 – 860 MHz| █ | Green
W| 21 – 68| 470 – 860 MHz| █ |Black
K| 21 – 48| 470 – 694 MHz| █ | Silver
E| 35 – 68| 582 – 860 MHz| █ |Brown


Proposed Aerial Groups
Option1 (no broadcast use of channels 31 – 38)
Group|Channels| Bandwidth| Colour| Code
L |21 – 30| 470 – 550 MHz| █ |Orange
H |39 – 60| 614 – 790 MHz| █ |Blue
T| 21 – 60| 470 – 790 MHz| █ |White


Option2 (broadcast use of channels 31 – 38)
Group|Channels| Bandwidth| Colour| Code|
L |21 – 38| 470 – 614 MHz| █ |Orange|Note1
H |31 – 60| 550 – 790 MHz| █ |Blue|
T| 21 – 60| 470 – 790 MHz| █ |White|


Note1 - New Group L not required if Ch 38 isn't used for DTT, Group A (21-37) will remain

reslfj

The Cush wrote: »

....
Option2 (broadcast use of channels 31 – 38)
Group|Channels| Bandwidth| Colour| Code|
L |21 – 38| 470 – 614 MHz| █ |Orange|Note1
H |31 – 60| 550 – 790 MHz| █ |Blue|
T| 21 – 60| 470 – 790 MHz| █ |White|

Note1 - New Group L not required if Ch 38 isn't used for DTT, Group A (21-37) will remain

New group L must include ch39 as the NImux uses ch39+

Lars

The Cush

Now that the spectrum auction is complete and the rollout of 4g services will be happening in the coming months the issue of interference to DTT from 4g will become an issue.

This has been an issue for RTÉ as we can see from the correspondence between them and Comreg/Dept during the consultation process on the multi-band spectrum auction (e.g. in the first post of this thread).

An article in today's Irish Indo says they have just learnt of this potential problem - http://www.independent.ie/business/technology/thousands-may-lose-tv-signal-at-home-in-rollout-of-superfast-4g-mobile-3350762.html

A Dept of Comms working group has been setup with RTÉ and Comreg to look at the issue according to the article.

Existing Dept of Comms/Comreg information on interference - http://www.dcenr.gov.ie/Communications/Business+and+Technology/Digital+Dividend/, http://www.comreg.ie/radio_spectrum/tv_reception_disruption.543.418.html

watty

Comreg are ONLY interested in raising revenue. Not protecting Spectrum or the Consumer.

EU should slap our Government REALLY hard for all the ***** they, DCENR and Comreg have fed EU and Public and failure to meet their mandate. Comreg daily break their own mission statement.

FREETV

watty wrote: »

Comreg are ONLY interested in raising revenue. Not protecting Spectrum or the Consumer.

EU should slap our Government REALLY hard for all the ***** they, DCENR and Comreg have fed EU and Public and failure to meet their mandate. Comreg daily break their own mission statement.

Watty you should contact Irish members of the EU Parliament and inform them of the ***** as you say that Comreg and Co are up to and state your expertise and that you once worked as an Engineer for the BBC. Hopefully they will listen to you?

watty

Various organisations have highlighted the shenanigans here. Such as NBS.

The Cush

The Cush wrote: »

An article in today's Irish Indo says they have just learnt of this potential problem - http://www.independent.ie/business/technology/thousands-may-lose-tv-signal-at-home-in-rollout-of-superfast-4g-mobile-3350762.html

Saorview replied to a comment on this on their facebook page

John Kilbride 15 January at 22:26
Is there any truth in the report in yesterdays newspaper stating that the rollout of 4g will affect Saorview reception

Saorview As things currently stand SAORVIEW are not aware of any planned activity which could affect reception quality. Representatives from RTÉ will be attending a working group, held at the request of the Department of Communications to discuss what television reception implications, if any, may arise from the rollout of the 4G services.
17 January at 16:19

http://www.facebook.com/#!/saorview/posts/445368302199861

They don't appear to be as concerned about potential interference as they were during the consultation process as we saw from the published correspondence between them and Comreg/Dept of Communications.

From: Kehoe, Mick [RTE]
Sent: 23 November 2011 12:28
To: Susan Fleming
Cc: DCENR’s Digital Switchover Group (DSG)
Subject: RE: interference between services in UHF bands

Susan,
I hope ComReg are right. RTÉNL stand by its position and at least if/when a problem does arise we will know where to divert the phone calls.

Regards,
Mick....

winston_1

To_be_confirmed wrote: »

In any case, there's very little that can be done until aerials and amps are finally manufactured to not specifically receive 800MHz broadcasts. I.e. Group C/D aerials and combiners etc. no longer tuned specifically to work from Ch. 61 to 69.

Aerials are not filters and won't sharply cut off at ch 60.

I have a 12 element ch 21 to 60 aerial made by Triax, a reputable manufacturer. It's from the days when German analogue TV only used up to ch 60. But its performance above ch 60 was better than than an 18 element Antiference C/D aerial.

The Cush

The Cush wrote: »

Article from this month's What Satellite & Digital TV magazine (#315, Summer2012)

At a recent CAI seminar they outlined proposals for new revised aerial groups.

- The 3 main aerial groups A, B, C/D would be reduced to 2 groups L, H.
- Aerial groups K, E would disappear
- The wideband group W would be replaced with a reduced wideband (21-60) group T (Triax has 4 "reduced-band" wideband aerials in its 2012 catalogue)

According to a news report in the latest issue of What Sat the CAI has started work on a new post DSO aerial benchmark standard which will reflect changes to broadcast spectrum such as the loss of the 800MHz frequencies.

A large meeting was held at the CAI HQ with the BBC, DTG, aerial manufacturers and distributors present.

"The CAI's executive has now begun a work stream to transform the parameters that define UHF TV aerials for the next few years."

What Satellite Feb 2013

lucernarian

winston_1 wrote: »

Aerials are not filters and won't sharply cut off at ch 60.

I have a 12 element ch 21 to 60 aerial made by Triax, a reputable manufacturer. It's from the days when German analogue TV only used up to ch 60. But its performance above ch 60 was better than than an 18 element Antiference C/D aerial.

That is just one example, its significance is negligible. And why would I or anyone else describe aerials as low-pass filters or anything approximating such?

There is enormous precedent for the merits of higher-gain aerials with narrower bandwidth. The various grouped aerials were produced for a reason. In a worst case scenario, the redefined-bandwidth aerials may offer gain at Ch. 61 of only 3 or 4 dB less than the highest gain the aerial offers, e.g. at Ch. 53. This should still be lower than would be received on Ch. 61 by a current Group C/D aerial and the supplied data with various aerials all show a drop in gain at the upper end of their design bandwidth. This may not make much of a difference but nonetheless an improvement in the "digital dividend" era.

It would be madness to propose making no changes to the bandwidth of UHF aerials when 4G transmission in 800 MHz has been identified as a serious problem.

The Cush

The Cush wrote: »

http://www.independent.ie/business/technology/thousands-may-lose-tv-signal-at-home-in-rollout-of-superfast-4g-mobile-3350762.html

A Dept of Comms working group has been setup with RTÉ and Comreg to look at the issue according to the article.

A Dáil question on this last week

Tuesday, 22 January 2013

418. Deputy Jack Wall
asked the Minister for Communications, Energy and Natural Resources his views regarding ComReg (details supplied); if his attention has been drawn to such problems and the actions to be taken to overcome same; and if he will make a statement on the matter. [2469/13]

Minister for Communications, Energy and Natural Resources (Deputy Pat Rabbitte): I am aware of the press article referred to by the Deputy.

This is an issue that will arise right across the EU as 4G services are rolled out and I can confirm that a group has been established by my Department to examine the degree to which this issue may arise in Ireland when the roll-out of 4G services commences later in 2013.

This group comprises officials from my Department, as well as representatives from ComReg, the Broadcasting Authority of Ireland, RTÉ and the mobile industry and its focus will be on assessing the potential for any interference in regard to households that use “free to air” television and to identify any possible remedial measures that may be required.

ComReg has already confirmed its view that any disruption that may arise to TV signals would be capable of being addressed by filters which are available.

It is my intention that an agreed joint strategy, as necessary, that fully addresses the issue should be put in place in advance of 4G roll-out.

http://oireachtasdebates.oireachtas.ie/debates%20authoring/debateswebpack.nsf/takes/dail2013012200070?opendocument#WRS00525

The Cush

Another Dáil question yesterday on potential interference that may be caused by the new 4G networks.

Thursday, 31 January 2013

33. Deputy Mick Wallace
asked the Minister for Communications, Energy and Natural Resources the outcome of the research initiated by him in relation to potential interference that may be caused by the new 4G network; and if he will make a statement on the matter. [4764/13]

Minister for Communications, Energy and Natural Resources (Deputy Pat Rabbitte): The issue raised in the Deputy’s Question may arise right across the EU as 4G services are rolled out. I can confirm that a group has been established by my Department to examine the degree to which this issue may arise in Ireland when the roll out of 4G services commences later in 2013. The group comprises officials from my Department, as well as representatives from ComReg, the BAI, RTÉ and the mobile industry and its focus will be on assessing the potential for any disruption to TV signals in households that use “free to air” television and to identify any possible remedial measures that may be required. The approaches being developed in other countries, including the UK, will be studied by the group and will help inform the approach that we will take in Ireland. ComReg has already confirmed its view that any disruption that may arise to TV signals would be capable of being addressed by filters which are available. It is my intention that an agreed joint strategy should be put in place in advance of 4G roll-out that fully addresses the issues around any potential disruption to consumers’ television service.

http://oireachtasdebates.oireachtas.ie/debates%20authoring/debateswebpack.nsf/takes/dail2013013100050?opendocument#WRD00750

The Cush

Digital Mobile Spectrum Limited (DMSL), originally called MitCo, the jointly controlled company formed by the 4 UK mobile network operators (EE, Telefónica O2, Three and Vodafone) with responsibility for ensuring that consumers continue to receive clear Freeview TV signals following the roll out of 4G mobile services is now up and running with the appointment of a Chief Executive and a new website.

DMSL website - Let's be clear at 800MHz

http://www.ft.com/cms/s/0/67e3ffdc-7394-11e2-9e92-00144feabdc0.html#ixzz2KjpLZNsV

Simon Beresford-Wylie, a telecoms industry veteran, will this week be named chief executive of Digital Mobile Spectrum Limited, the group charged with ensuring Britain’s terrestrial TV will not be knocked out by 4G mobile services.

“The 4G networks will likely be running from this summer,” Mr Beresford-Wylie said. “We need to be fully operational by March to be in place to mitigate any interference issues.”

The government has raised £180m from the mobile groups who will use 4G spectrum (an amount separate from the £3.5bn the Treasury is expected to raise from auctioning the spectrum) to pay for the filters as well as a nationwide advertising campaign to alert home owners to potential problems.

Engineers will be employed to make home visits to fit the devices where necessary, although the filters are designed to be fitted by home owners in most cases.

Mr Beresford-Wylie said DMSL would work closely with broadcasters and mobile network operators to build a “sophisticated model” to predict where interference might occur, and to provide filters accordingly.

Before the 4G launch, DMSL will conduct pilots to ensure that solutions work and to help find problem areas.

“We expect to be able to identify affected households,” Mr Beresford-Wylie said. “We will need to procure millions [of filters] in the first instance.”

jjf1974

Can we expect the same problems in this country ?

The Cush

jjf1974 wrote: »

Can we expect the same problems in this country ?

Probably.

Households prone to interference from mobile masts will include those close to mobile transmitter sites, aerials with masthead amps, reception from transmitters that use UHF Ch.52 upwards, indoor aerials etc.

Hotblack Desiato

Hmm. We live less than 1km away from a mobile/Digiweb Metro site, which is the highest point in the area, almost exactly in line between our house and Kippure, and we have a wideband aerial. Sounds like the ideal recipe for interference if that site is used for 800MHz and chances are it will be...

The Cush

ninja900 wrote: »

We live less than 1km away from a mobile/Digiweb Metro site, which is the highest point in the area, almost exactly in line between our house and Kippure, and we have a wideband aerial. Sounds like the ideal recipe for interference if that site is used for 800MHz and chances are it will be...

That could be the case, a quote here from the ukfree.tv website

Interpreting the aerial and mast locations

Once the proposed mast locations for 4G services are known, it will then be possible to predict which homes will need to fit the special filters in areas where Freeview uses the higher channel numbers (the C52 to C60 range).

If you then have a rooftop aerial without a signal amplifier, to get an overload you will need the 4G mast to be in the line-of-sight between your Freeview transmitter and the aerial, or possibly "directly behind" the aerial.

If you then have a rooftop aerial and an amplifier, or perhaps have lower-grade cables, you are likely to need to protect from a 4G overload if the phone mast is close to your rooftop aerial.

http://www.ukfree.tv/fullstory.php?storyid=1107052059

Maybe the Dept of Comms or Comreg or RTÉ or the MNOs with 800MHz spectrum will provide the necessary filters to those household affected by LTE interference, then again maybe not :rolleyes:

The Cush

Irish authorities to investigate if 4G will disrupt TV signals in homes - siliconrepublic.com

...

So, will TV in Ireland be affected when 4G goes live?

In response to queries from Siliconrepublic.com, Ireland’s Department of Communications, Energy and Natural Resources confirmed it is evaluating the issue arising in Ireland.

“A group has been established by the department to examine the degree to which this issue may arise in Ireland when the roll out of 4G services commences later in 2013.

“This group comprises officials from the department, as well as representatives from ComReg, the Broadcasting Authority of Ireland, RTÉ and the mobile industry, and its focus is on assessing the potential for any interference in regard to households that use ‘free to air’television and to identify any possible remedial measures that may be required. It is the intention that an agreed strategy, as necessary, that addresses the issue should be put in place in advance of 4G roll out,” the department spokesman said.

When we contacted telecoms regulator ComReg on the issue we were directed to an FAQ that confirmed that homes in weak signal areas that previously had to install a masthead amplifier – a small plastic box – on their rooftop aerials to get a decent signal might be affected.

Homes using the free digital television service Saorview are unlikely to be affected, the FAQ says, because Saorview factored its service in for use without the need for amplifiers.

However, amplifiers are likely to be still in use in homes located in areas of weak signal or coverage blackspots. These homes or homes that use amplifiers to boost a TV signal to a number of other TVs in the household are likely to experience radio frequency (RF) overload when 4G is switched on alongside the new digital terrestrial TV services.

ComReg says: “If you receive off air reception of the national services (RTÉ, TG4, TV3) by means of a roof top aerial which is fitted with a mast head amplifier, you may suffer degradation or even loss of television reception when LTE services come on stream from early 2013 onwards. This loss is likely to be as a result of the amplifier on your roof amplifying an unwanted signal and suffering overload.”

...

Comreg FAQ - What is Radio Frequency (RF) Overload and how might it impact me?

byte

Interestingly, the Johansson wideband amps now have Lte logo on them and only cover E21-60, which is handy. Do other amp brands do similar? Triax don't seem to, though not a fan of their stuff anyway.