Live Field Acquisition

I hope this is the appropriate forum to post in. I did a quick search and found no results.

I've seen a few pictures from photographers and reporters from ITV and the BBC in multiple regions of OB trucks/vans used for live reports from the field. All these trucks seem to rely on satellite technology to get the images back to the station. Here in the US satellite news gathering are used but most stations prefer to use microwave technology to get their signals back to the station using vans with a mast and a dish on top. The stations here prefer using microwave technology to get signals back to the station because they own the spectrum that they use and it's free. In case you don't know what I am talking about here is link to one manufacturers product range where the vans use microwave or satellite technology or a both. I do remember seeing archived articles and photos of this technology in use but none from the past decade.

Is there any particular reason why the broadcasters seem to have stopped using this technology in favor for satellite? I imagine ITV and the BBC have satellite capacity reserved for this purpose (as do US many station group owners here) but surely is much more costly than microwave. I will say I have seen temporary point to point microwave systems set up for certain events where SNG is not the best possible option.

Microwave is line of sight. You have to have a receiver in view of your ENG van or it wont work. SNG on the other hand is much more flexible, and once you discount the cost of the fixed receiver network the running costs won't be much different.

Remember in the UK broadcasters don't own any radio spectrum they use, microwave or satellite, they only rent it off the government, so there's a cost to using microwave as well as satellite.

Also to use microwave often required a visit to the transmitter site (where the receivers were/are) to align the dish to receive the contribution. Plus if you weren't in direct line if sight you'd need anther links vehicle to act as a midpoint, with further staffing costs.

It's important to remember that in the US TV is local, and may only cover a single large town or city, so a single hop-microwave link is useful for covering a large section of the area covered by a station. In the UK our large TV operation is regional, not local, often covering lots of large towns and cities over a much wider range, and in some cases the geography is such that line-of-sight links are useless. In the UK we have bigger regions that need to cover areas far further away than a line-of-site microwave link could be used over, even with multiple, remotely steerable, receive points on the main transmitter sites (which is how BBC microwave links used to be engineered)

Microwave point-to-point links were widely used in the 80s and 90s for regional and network news coverage, but they were far less flexible than satellite, and in some cases you'd need to deploy one or two mid-point receive/transmit trucks to extend the range past what a single hope could cover.

AIUI one reason that microwave trucks are popular in the US is that one of the main cellular operators paid for equipment upgrades when they purchased the spectrum previously used for TV links and as part of the deal had to replace TV stations' gear with new stuff in a different band.

They are still used with digital broadcasting for some network programmes - particularly as you can get a high bitrate circuit for less money than satellite if you need it for hours on end, and it can work effectively as a backup for a high-profile show.

Remotely steerable dishes were fitted to many BBC receiver sites to allow for remote line-up with regional FRVs. Certainly that was the case in the Look East patch when they only had a microwave FRV in the 90s. The same links were also used for regional contributions from local radio studios - so you'd have to remember to pan the receiver dish back to the right location after an FRV hit, so down-the-lines could happen from, say, 3CR in Luton... (I think Luton and Ipswich were both microwave-linked contribution studios, whereas Cambridge was fibre)

I think I'm right in saying that the glass windowed room at the top of Emley Moor was designed to make rigging OB receive points easier - at conventional sites somebody had to climb the mast to set it up, but at Emley they could just put a dish behind the window which was made of a special glass for the purpose.

I am looking at maps of ITV now and I had no idea how big and how many masts a region has such ITV Granada'which serves about three million homes from 80 masts. I guess I figured that the region may have two or three main transmission sites to cover a region. I assume many of those translator stations are used in areas where the main signal is blocked by different topography. From a simple cost factor I now see that it would not be practical but that being said how are the smaller transmitter sites fee - are they fed via fiber or are rebroadcasters of the main masts?

Here US stations usually have multiple remotely steerable receive sites and relay links across the city which usually now seem to feed back to the station via fiber.

As to the cell company Sprint only replaced preexisting equipment during their 2GHz relocation.

That being said how are signals from a news organizations helicopter sent back to the station? Here news helicopters have directional antennas sending signals to different receive sites. Both the transmission antennas and receive sites automatically move in relation to the helicopter.

Granada is unusual in having just one main transmitter site, which prevented it from song sub regional opt outs for news news from a particular half of the region our targeted advertising.

The smaller sites which fill gaps in the coverage of the main transmitter are known as relay transmitters because the majority are off air rebroadcast, however some do use microwave/SHF for at least part of the path. Some sites right of as relays are line fed (but maybe not for all services), either where there is no line of site from another station with the correct regional variation, or upgraded where the original off air feed was found to be unsatisfactory or where a sub opt was introduced after the station opened.

All main sites are fibre fed, as are some of the smaller sites. There are facilities within DVB-T to do translation (or simple tweaked rebroadcast I believe to avoid small relays needing fibres). In some areas of Europe you can also use 'on frequency' fill-ins (as DVB-T/T2 allows for single-frequency network working due to the large guard bands that can be deployed in COFDM)



Yep - some BBC regions had remotely steerable dishes, but to cover much larger areas than a city.


Yep - but chatting to US friends, quite a lot of pre-existing gear was converted, and it did mean fewer thoughts about SNG trucks.



Helicopters are used far less than in the US, but they normally use a microwave link to a number of receive points. Helicopters are only used live by network news usually in the UK, not by regional news.

Of course with the advent of LiveU and WMT type 3G/4G/WiFi bonded back-pack links - which are delivering picture quality pretty close to HD SNG (and better than SD SNG) in good signal areas, the 'truck' is not always needed for a high quality live shot any more...

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How do you work there sounds like my type of place