UK.gov vows to purify TV with £180m from mobile networks

I thought that the point of all this digital TV stuff was to free up channels that we couldn't use at the time because they would interfere. The concept was, correct me if I'm wrong, along the lines of:

"We'll move all the TV into its own frequency band that takes up less room - then that leaves us buckets of old very sought-after analogue space that we can use willy-nilly and not worry about taking out someone's TV signal".

I will never understand Ofcom and frequency allocation at all. Either allocate something or don't. If you do allocate it, your whole JOB is to make sure it doesn't interfere with others at all. That's it. That's all you have to worry about. And you can't even do that.

£10,000 per house if your tv reception gets affected? I hope I'm one of the lucky ones!

Why don't we just plan to give up Freeview and put 4G in tellies? Surely if 4G speeds are knocking around the airwaves anyway, it's enough bandwidth to stream channels. You can then stop broadcasting Freeview and make way for 5G.

The sooner we get *everything* delivered via internet the better (mobile phones, freeview, FM).

And if you think my idea is too far fetched, you missed the bit where this current plan allows up to £10k PER HOME to upgrade to freesat.

My understanding of the £10K amount was that would only be for the tiny proportion of houses where any of the normally viable alternatives (sky, freesat, virgin, etc) wouldn't be possible.

Regardless, the whole thing is a bloody shambles, and I'm going to be well pissed if my reception (from the Angus transmitter) is affected. It uses two frequencies above 786Mhz from what I can tell.

What's the source of the story, what's their agenda?

Saw this on the BBC yesterday.

Not convinced it makes a whole lot of sense. Who published the press release, and what is their agenda?

Sure, like the case with LightSquared and GPS, strong interfering signals some way from the wanted (weaker) frequency can get through the receiver's insufficient filtering and cause problems. (And contrary to previous poster, wideband booster-amps /can/ saturate or create other intermod distortions.) Even so, bearing in mind that Freeview receivers have worked in recent years in the presence of much stronger ANALOGUE transmissions (usually from the same transmitter mast) so aerial equally aligned and on almost adjacent frequencies... I'd've thought the receivers should have pretty good off-frequency rejection. I can believe that there will be a very small minority of houses with genuine reception problems (e.g. where the 4G mast is only 50 yards from the customer house and in line with the TV transmitter, so the customers aerial is pointing straight at it), but 760000 homes affected sounds an awful lot...

Ch 60+?

By the time LTE gets going there won't be any TV signals on channels above 60. The interference will be worst in Ch 60, decreasing for 2 or 3 channels below that, and then not really a problem below that. Unfortunately OFCOM decided on skirt filter specs for LTE transmissions that mean there is still significant signal power at the top edge of Ch 60. Assume I'm beaming to my local TV transmitter on Ch 60 but there is a LTE basestation more or less on the same bearing. Even if I could put a brick-wall low-pass filter in front of my masthead preamp, I will still get significant LTE signals overlaying the DTT one. If I don't use a filter, the much stronger LTE signals just above Ch 60 will get into the preamp, perhaps overloading it, and into the receiver front-end, perhaps overloading that too.

£10k per house sounds a lot for amelioration. A Freesat installation will be much less than that. It won't work for everyone though.

A more complete explanation

There is a rather better explanation of the issues here, which are by no means limited to using channel 60 with signal boosters. It appears that if you have a signal booster near a 4G transmitter it could kill the entire Freeview service or, if you are really unlucky, even without a booster. That's due to overload of signal levels into either the booster or the receiver.

The adjacent channel 60 interference issue also applies, but it's far from the only issue.

http://www.ukfree.tv/fullstory.php?storyid=1107051834

One thing that does occur to me as that this is based on modelling the 9,000 or so 4G base station. However, what about the mobile devices themselves? No doubt they are much lower powered than the base station, but many will be a heck of a lot closer to the TV aerials, and the inverse square law applies.