Surveying the DTV landscape with GatesAir

Every continent and region has its unique needs and challenges when it comes to digital TV transmission. However, the Asia-Pacific market, including Southeast Asia, stands apart due to its embrace of different standards. Today’s digital television landscape demonstrates extraordinary diversity – while DVB-T and increasingly DVB-T2 remain the most widely adopted, such as in India, we also see ISDB-T (Japan, Philippines), DTMB (China), and even ATSC 3.0 (South Korea) supporting DTV initiatives.

All of these standards will provide broadcasters with the DTV benefits they seek:

• The delivery of more programs and media services
• Improved reception, with perfect picture and sound
• The same coverage as analog, at less power
• Let us explore each of these in more detail.

More choices, new services
First, the delivery of more programs and services is made possible through the far more efficient bandwidth of digital streams. Where broadcasters traditionally could count one analog program through a single RF channel, multiple digital programs can now be delivered using the same spectrum.

Digital encoding and multiplexing technologies in the headend play a significant role in compressing signals ahead of the RF architecture, while today’s advanced digital-modulation techniques provide integrity through the transmitter. At this stage, a GatesAir transmission system provides the headroom, signal correction, and other capabilities required to prepare the signals for over-the-air delivery.

Picture perfect
Improved reception is no mystery with digital TV – the days of fuzzy analog pictures on the edges of the coverage area are gone forever. However, the perfect picture and sound immediately drops at the edge of the coverage area. Today’s leading-edge standards – notably, DVB-T, DVB-T2, ISDB-T, and ATSC 3.0 – allow broadcasters to adopt single-frequency network, or SFN architectures that are designed primarily to solve this problem.

SFNs deploy multiple, overlapping transmitters of low-to-medium power levels, with very-low-power gap fillers to fill in the most difficult-to-reach areas. This is especially important in countries of challenging terrain or multiple islands, with Indonesia being an excellent example.

Lower operating costs
Transmitter efficiency continues to rise both in numbers and in importance to broadcasters; as an example, GatesAir’s Maxiva transmitters currently provide up to 45 percent efficiency – a staggering increase from previous generations of digital transmitters. The higher efficiency is a substantial driver in cost savings in many ways, chief among them is that broadcasters cover the same ground with less power. This is particularly important in SFN architectures with multiple transmitters on the same frequency, sending out multiple programs with less electrical energy consumption.

Broadcasters transitioning to current-generation transmitters will cut power usage by at least 40 percent, in most cases. Meanwhile, the continued migration from tube to solid-state transmitters is further lowering costs through streamlined maintenance, improved redundancy and diagnostics, and less expensive spare parts with easier availability.

With experience in digital transmissions worldwide, GatesAir is currently working with broadcasters in India and throughout Asia to help establish the right transmission system for their choice of standard and coverage requirements. From optimizing antenna-radiation patterns all the way through working with regional partners to design, install, and commission the infrastructure, GatesAir is well prepared to help broadcasters managing the most challenging DTV transitions imaginable.