In Broadcast - September 2015 - 30


30

www.inbroadcast.com | Vol: 5 - Issue 9 | September 2015

InForm

Setting Up An Independent
Wi-Fi-Over-IP Live
Broadcast Solution
Andy Smith, Lighting Cameraman at Firstsight
Communications & Owner of IP Broadcast TV,
discusses the benefits of using IP-based
transmission systems...

A

s a self-employed Lighting Cameraman since 1997 following 16
years with the BBC, I know you must
evolve with technology to be successful.
With that in mind, I had to refocus my
services last year to satisfy the changing needs of my clients, which resulted
in the establishment of my own mobile
broadcasting facility for the field.
With considerable live camera
experience and a suitable knowledge
of
satellite
communications,
I
purchased an H.264 encoder and an
entry level Ka-band satellite uplink,
constructed the antenna mounting
hardware, arranged the power supply,
and integrated the system. I also
preserved the life of my Sony PMW500 camera. That left me with one last
challenge to tackle.
In today's environment, the wireless
link between the camera and the
satellite uplink vehicle is essential.
Beyond effectiveness, there are health
and safety concerns about laying
cables across pathways and other
egress areas. I looked into traditional
COFDM (Coded Orthogonal Frequency
Division Multiplex) systems, but the
units were prohibitively expensive for
a single business owner like me.
I decided to test out an IP-based
transmission system, which encodes
your video to an H.264 IP stream
before the data is transmitted via
a Wi-Fi path to the receiver. Wi-Fi
transmission is license exempt in the
UK - a major advantage that is not
available with current COFDM systems.
RX with
Satellite Dish

After some research, the best option
was the cost-effective Teradek Beam
solution.
My first hurdle in putting together
a robust live facility had to do with
proxemics. In my day-to-day news
operations, it's more often about
where you can park to have a clear line
of site to the satellite, and where the
camera needs to be to see the action.
Distance is not such a problem. Joining
the two parts with the Teradek Beam
solved this for me. I was able to get
very similar quality images compared
to pictures out of the camera, beamed
directly to the broadcaster. Although
harsher compression on the link can
affect picture quality, it's selectable. I
choose 12mb for all my operations.
My next challenge was latency.
Obviously, low latency is quite
important in a live broadcasting
environment. You have to consider
everything from the signal chain that
might affect the delay, like when your
presenter answers a question thrown
from the studio. Teradek claimed the
Beam had a latency of two frames,
which is about 80 milliseconds. With
the complex processing that occurs
behind the scenes to get the picture
across the link, this was quite an
impressive claim. What I really wanted
to do was measure it, so I recorded a
link latency of 2.5 frames and the lip
sync was perfect. There was barely any
difference between the Beam and a
cabled link.
Granted, an IP solution is not quite
as robust as a COFDM system, but
it's much more affordable, uses
less power, and weighs less on the
camera since it's a smaller unit. With
the proven triumph of my initial
product testing, I've since committed
to the Teradek Beam system, and
incorporated it into my workflow, using
it to great success on several projects,
including two for the BBC.

Ready to roll...
Teradek Beam
Receiver

On the BBC's flagship evening news
programme, we were called out to
Harwich International Port because
suspected illegal passengers had been
discovered stowing away on a ship.
The lead story of the day covered 68
people who were apprehended trying
to get into the UK from Holland. There
was an area where we could park, but
the best view of the ship was about
30 to 40 metres away and across a
roadway. Cabling was impractical, so
we established a wireless link between
our vehicle and the best viewpoint for
the camera and, with Beam, everything
worked perfectly.
For Newsnight on BBC Two, we had
a very different situation. During
the build-up of the general election,
the programme profiled several
different families on their views
and the candidates they favoured.
Two nights before the election, we
were dispatched to a family's home
in Swansea, Wales; I parked in their
driveway and we shot inside. In this
case, I could have cabled it quite easily,
but it was much more convenient for
me - and the householder - to avoid
the wiring. It was one less thing for me
to worry about in the end.
We utilised wireless IP-transmission
in an entirely different way at
the National Exhibition Centre in

Teradek Beam
Receiver display

Birmingham. My client wanted live
pictures transmitted to a big video
wall in the enormous exhibition space.
The receiver was mounted as high
as possible on a lighting stand. My
colleague was able to go around to all
the stands - amongst all the people -
and get the images back to the screen
via a radio link.
Beam provided faultless pictures
throughout the day, mostly from about
60 metres away from the RX with
heads and exhibitions obstructing the
signal pathway.
Since they had been looking to hire
a COFDM system separately for the
event, the client was delighted. Their
hire rate would have been around
£600 to £700 (approximately $930
to $1090) for the day, and they
would have also needed an engineer.
With our system, it was completely
unnecessary.
In short, finding a reliable short-tomedium range radio camera system
has given me the flexibility and
cost savings necessary to offer live
broadcast services, in a landscape
where clients are more and more in
need of a variety of solutions. I've
replaced the fibre between my camera
and vehicle, overcome range and
latency issues, and added another
notch to my services portfolio.
http://www.inbroadcast.com http://teradek.com/collections/beam http://teradek.com/collections/beam
Table of Contents for the Digital Edition of In Broadcast - September 2015
