DVB-S2 compatibility is now commonplace in satellite receivers designed to receive HD TV services. Almost all HD channels use the DVB-S2 standard. However, not all viewers have DVB-S2 compatible receivers in their homes, such as those Sky subscribers with old Sky digiboxes.
But this situation is stopping broadcasters wanting to make use of the bandwidth-saving properties of DVB-S2 and those wanting to stop broadcasting in standard definition. And it seems, this current state of affairs is putting some broadcasters off launching UHD services.
On Wednesday 18th November, while all eyes will be on the launch of Sky's new receiver in the UK, Sky's German arm is expected to complete the transition of all of its services to the newer DVB-S2 broadcast standard, which will free up satellite capacity for other purposes, such as the eventual launch of UHD services.
Fortunately, Sky's receivers for the German and Austrian market are all DVB-S2 compatible, meaning the final changes made this week should go unnoticed for the majority of viewers.
In the UK and Ireland, a legacy of older Sky boxes that don't support DVB-S2 means that broadcasters cannot realistically start switching satellite broadcasts to DVB-S2 without risking the loss of viewers who don't have compatible equipment. To date, Sky has not made any announcements indicating it's going to stop supporting older receivers or start a mandatory swap-over of equipment.
And this is a problem for broadcasters who want to make better use of their satellite capacity. A broadcaster with many regional variants to cater for, such as the BBC and ITV, could use a switch to DVB-S2 to maximise efficiency: the same number of channels using less bandwidth.
Realistically, by the time all households have DVB-S2 compatible receivers, the BBC will be wanting to cease broadcasting in standard definition altogether, after it has completed its planned roll-out of HD regions and nations, due to start in the next BBC Charter period. Commercial broadcasters may want to follow Channel 5 in abolishing linear regions, and allowing Sky's AdSmart technology to push targeted adverts to viewers instead, although for ITV this would mean going to Ofcom and pleading for a further reduction in its regional commitments.
While it would be easy for Sky to order a swap-out of its older SD-only receivers for DVB-S2 compliant ones, there will be a small number of perhaps not very tech-savvy households who have a basic Freesat SD box, perhaps received as part of the digital switchover help scheme, with the aim of providing basic access to TV services, that may need assistance.
SD TV stopping UHD TV?
There are signs that viewers watching in standard definition on non-DVB-S2 compatible devices is stopping broadcasters from offering more in Ultra HD.
Last month, Andreas Bereczky, from German public broadcaster ZDF indicated that ending SD/HD simulcasting would be a requirement for his channel to start broadcasting in UHD. While Sky is switching to DVB-S2 in Germany, theoretically meaning there's no need to broadcast in standard definition, there is a much higher percentage of viewers using free-to-air satellite receivers in the country than in the UK, where Sky dominates the scene. This means that German broadcasters expect that they'll have to wait until 80 - 90% of viewers have made the switch to DVB-S2 before they look at closing SD services. ZDF isn't the only broadcaster that feels that the HD transition needs to be sorted out first before making UHD a priority.
How programmes are shown via satellite may become less of an issue in the future, of course. Sky's new receiver looks set to harness the power of internet-delivered services, although its core linear channels will always be received via satellite, especially when Sky chooses to launch Ultra HD versions of its channels. Distributing these services via satellite will give Sky an edge over BT, who can only offer UHD to viewers who live in an area with sufficient broadband speeds and who can also afford the premium of both fibre broadband (beyond the initial discounts) on top of a UHD subscription.
UHD, in turn, opens up the possibility of the adoption of DVB-S2X, an extension of DVB-S2, which promises to offer efficiency gains of around 50%, giving broadcasters more space for bandwidth-hungry UHD channels.
With Sky's new receiver look set to become part of its new top-range service, there might be scope to push older Sky+HD receivers to standard definition subscribers in order to encourage change and efficiency for broadcasters, not least Sky, who would be able to launch UHD services using former standard definition channel capacity and keeping a lid on satellite capacity costs.
It seems just three years after the last analogue services were switched off, first generation digital TV services have taken analogue TV's place in being a hurdle for future advancement.
Perhaps now is the time to refurbish and redistribute Sky+HD boxes from those who upgrade to SkyQ to help the transition along a bit...
SD/HD DVB-S/DVB-S2 explained
- Most HD channels use the DVB-S2 broadcast standard, as it allows broadcasters and satellite TV operators to make the most of their available satellite bandwidth.
- All HD satellite receivers are DVB-S2 compliant.
- If DVB-S2 was made mandatory and standard definition broadcasts ceased, viewers with older non-HD TVs would be able to watch a downscaled version of the HD channels. There wouldn't be a need to retain a separate standard definition version of the channel.
- However, standard definition channels could continue to exist using DVB-S2. Each standard definition channel would use less bandwidth than now, meaning that it could cost less to distribute a channel via satellite. That might be of interest to smaller, niche broadcasters.
- In the UK, the extra charges for HD levied by Sky have put some cost-conscious subscribers off from upgrading to to HD, although the main channels such as BBC One HD and ITV HD are free-to-air. Most Freesat boxes in circulation now also support free-to-air HD TV channels.
- Similar moves are pending for terrestrial TV. Non-HD Freeview boxes may become redundant around the end of the decade.