Cable & Satellite FAQs
Can you run past me some of the advances and major differences between DVB-T2 and its predecessor?
A subgroup of the DVB Project is currently defining the DVB-T2 standard in detail based on the compiled commercial requirements. Therefore, any statements about DVB-T2 would be preliminary at this point. From the standpoint of Rohde & Schwarz, and based on the project status as of February 2008, significant innovations to DVB-T will focus on the following topics:
- New forward error protection
- High-order modulation modes
- Variable modulation and coding of services
- Increase in the number of OFDM carriers
If MIMO were added to the mix, what would the practical implications of this move be?
Whenever either a MIMO (multiple input multiple output) or a MISO (multiple input single output) approach is used, it is reasonable to expect an improvement in robustness and a reduction in destructive interference in single frequency networks (SFN).
What do you see as the main drivers behind DVB-T2?
High-definition television (HDTV) and more programs per terrestrial transmission channel are the driving forces. These features are required of a new or at least an improved terrestrial transmission method. New technologies make it possible to meet the need for higher data rates for the terrestrial transmission of video and audio signals.
And the main challenges?
One of the biggest challenges for a successful introduction of new technologies is adding value for and being accepted by TV viewers. Only when they perceive a clear advantage will viewers be willing to accept the added expenditure. Another challenge is to fulfill country-specific regulations that specify the use of television channels in detail.
What is Rohde & Schwarz’s involvement in, and plans for, DVB-T2?
Rohde & Schwarz is a member of the “Technical Module” of the DVB Project and, as a technology leader, is also ready to support these new technologies. This applies for test and measurement solutions as well as for terrestrial transmitter solutions.
Similarly, could the use of this technology enable terrestrial broadcasters to launch in-band mobile TV services (similar to the proposals in the US)?
In principle, mobile TV reception is already possible with DVB-T, but from our standpoint, it is not a development goal for DVB-T2. The DVB-H standard is more pertinent in this regard.
Can you clarify what the role of IP is in DVB-T2, and its relationship to MPEG TS? I understand that GSE (generic stream encapsulation) to be used in DVB-T2 is just a more efficient way of putting IP into the MPEG TS?
At the moment, both MPEG-2 transport streams and GSE baseband signals are included in the DVB-T2 draft. Proposals are still being worked out as part of the discussion as to how high the efficiency gain could be due to the use of GSE signals.
Would the above point to a more deepening embrace of IP by “traditional” broadcasters?
Every new technology should bring advantages for users. From the standpoint of broadcast providers, an increased use of IP technologies can help to reduce infrastructure costs. As a result, a trend toward the use of IP is apparent already today.
What’s your understanding of DVB-T2’s patent issues and what’s happening on this front?
A number of different patents are typically involved in the introduction of new technologies. To ensure that the legal rights of patent holders are sufficiently covered, a patent pool is usually formed that represents the interests of the patent holders. This could only be answered by them.
In your opinion, what’s the best way for DTT to manage the transition to DVB-T2?
It’s too early to answer this question because the actual DVB-T2 specification hasn’t even been adopted yet. At any rate, individual local markets will ultimately decide how successful the introduction of DVB-T2 will be. In many areas, analog television has been replaced as a result of a complete switchover to DVB-T. In contrast, Rohde & Schwarz is working from the assumption that DVB-T2 will be introduced in parallel to the existing services. In this way, network operators will be able to offer additional, high-quality services for their viewers.
