Cory Edwards
Global Sales Manager of Dielectric
Where high-power transmission has long been the favoured
platform for over-the-air (OTA) TV delivery in North America, much of the remaining
world has long favoured lower-power systems. Low-power transmission systems, notably
single-frequency networks (SFNs), help broadcasters effectively reach local
populations and manage challenging terrains.
That is especially viable
throughout the Asia-Pacific region, where countries such as Indonesia and the
Philippines manage TV delivery over thousands of islands. Today’s advanced
digital TV standards, including ATSC 3.0, DVB-T2 and ISDB-Tb, are all used in
various Asia-Pacific countries — and often leverage SFN architectures and
low-power systems.
The Philippine market has been
especially active for Dielectric. Many broadcasters are in the early stages of the
DTV transition, which is slated for completion by 2023. Our local partner 90
Degrees North has seen brisk business, including a deal with Broadcast
Enterprises and Affiliated Media (BEAM) covering RF filters, combiners and
transmission line.
All of these matter when planning
an SFN.
Each network site foremost requires
the appropriately defined directional antenna patterns, power levels, network
timings, and heights above ground level, for example, to ensure proper
synchronization, coverage, and removal of overlapping signals that cause
interference. Beyond antennas, these sites also require properly matched
filters, combiners, switches and transmission line to optimise SFN
functionality.
Dielectric’s Powerlite Series was
initially developed to address low-power TV and FM radio budgets. As these
systems combine antennas, transmission line, tunable filters and other RF
components into all-inclusive packages, they have also proven valuable for
broadcasters transitioning to low-power DTV systems.
The most recent Dielectric
innovation in this space is the Powerlite TFU-WB-LP Series, which is the first
to specifically target ATSC 3.0 systems. We have added support for nearly 20
additional antenna patterns that apply not only to ATSC 3.0 SFN systems, but low-power
TV systems worldwide.
The big question remains: How does
a network operator efficiently manage all of the requirements that bring the RF
ecosystem together? For example, the challenge of designing an RF mask filter
for each site that customised for power and tunable channel at each site.
It comes down to software and
planning. Over the past year, Dielectric has released online tools that allow
broadcasters to develop
advanced, software-based antenna and RF designs over the web. This includes
Dielectric’s Proposal Generator software to streamline low-power antenna
technical proposals. With this software, users can clearly see how design
choices impact the antenna performance. The software also removes the “back and forth” process of review
iterations to perfect the design. Users can directly enter values for the
following information:
- Location, channel and frequency
- Antenna model, azimuth and elevation
patterns with polarization selection - Evaluate wind loading and other
mechanical specifications - Inputs to automatically calculate
antenna gain and transmission line losses
As broadcasters shift to
next-generation TV standards and systems, these advanced RF systems and
software design tools will allow for quicker fulfilment of TV orders in the
Asia-Pacific region, which largely operate lower power systems, and at a lower
overall cost to the end customer.
Powerlite antenna technical
proposal software is readily available for download for free from the software
section of Dielectric’s website.