SatBroadcastingSNGs New Edge
By Paul Seguin, Application Specialist, C-COM Satellite Systems, Inc.
A quick review of the Broadcast Industry and its use of Satellite technology suggest some very interesting information. Prior to the use of satellite, video images shot on site needed to be put on tape and hand delivered to a studio for editing and broadcast. While this provides a secure delivery method, it could prove to be a very lengthy process, making the event being covered less than "current". As all agencies were in the same position, the public was used to this obscene delay, and it was considered a normal course of events (e.g. during World War 1, stories were often submitted by Post).
The obvious issue with this type of delivery was the location of the event being filmed; if not sent by Mail, it would have to be carried a long way before it could be reviewed, edited and broadcast over the air. A shared system was installed in certain large cities where a video tape player would be located in a building. A hardwire communication line was installed such that a story could be uploaded to the appropriate news agency for editing. These portals provided a way for agencies to upload stories quicker than it would be to transport the tape back to the studio. This advancement meant that the time between the event and the viewing could be reduces to hours, rather than days.
The thought of using a satellite to transfer data was very intriguing to the broadcast engineers of the day. If you could use a fixed antenna system to do this job, why not use a slightly smaller antenna to broadcast images captured in the field. The real problem was: how does one move a 4.8m fixed antenna around and get it setup in reasonable time to make it quicker than driving the tape back to the studio. Studios had just begun to use C-Band antennas to upload stories filmed or composed locally to an office in different location. The studios would receive feeds from other affiliates and sources that they would then broadcast over the airwaves to their viewing audience.
Moving forward, a gentleman named Dudley Freeman, from Massachusetts, decided that there was a way to install a 4.8m antenna on a truck and drive to the required location to upload the video captured at the event. In fact, with some creative electronics, the video could be transferred live back to the studio.
Mr. Freeman found that by folding the edges of the 4.8m antenna and by locating the antenna at the right physical plane, it could just fit on the back of the truck without any overhang. As this was C-Band, and the efficiency of the satellite was not very good, high power amplifiers (BUCs) needed to be used. It was standard to use two 600 watt (or higher) amplifiers to provide enough power, plus a redundant device should a failure occur. These amplifiers were of the type TWT (Travelling Wave Tube) and required that the tube be allowed to warm up to temperature before the frequencies would stabilize and they became usable. The tubes in the amplifier required vast amounts of power to operate; so, the trucks had to be equipped with high power generators to produce the required voltage and current. It was normal for a 12.5kw generator to be installed in the truck to power the system.
These trucks were a marvel of modern broadcast electronics and typically would cost north of a half a million dollars. Due to the amount of equipment and the size of the reflector they carried, they were typically installed on a 5 ton truck chassis, with a large box body. These trucks could be used to uplink to any satellite needed in order to transfer video and audio from any event that was newsworthy.
These early broadcasts would push an analog video and audio of Standard Definition quality that required a whole transponder for one video image. If multiple camera feeds were to be used, multiple transponders needed to be available. Obviously the cost to use a whole transponder was quite high. Only the really worthy news events would warrant using these live feeds.
Once the market saw the usefulness of these trucks, some smart operators began to build such vehicles with the sole purpose of renting them out to news agencies that needed to uplink a story. These users would listen for the intelligence of the day and drive their trucks to the location of the newsworthy stories. Once on site, the operators could sell their uplink services to whichever agency had sent reporters but had no satellite truck of their own. This allowed for live feeds from these events to be picked up and carried as either a breaking story or on the next scheduled news broadcast.
The use of these large antennas and C-Band satellites continued until late 1990's when some operators began to build trucks to use Ku-Band satellites. The Ku-Band operates at a higher frequency than the C-Band; so, the antenna size can be smaller, the amplifier needed to push the same amount of data could be smaller, and the transponder had more capacity. C-Band was typically 36 MHz whereas KU-Band is typically 27 MHz or 54 MHz, so less than a whole transponder was needed to upload a story from the field. Having smaller antennas and amplifiers meant that the truck size could also be smaller. In addition, a smaller truck was more nimble getting to and from the event, and less expensive to keep on the road.
A 2.4m antenna became the choice for the new trucks that were being built. Ku-band, being a smaller wave than C-band, required lower transmission power, and thus, a smaller BUC was needed. Ku-band bandwidth was more expensive than C-band, however, more transponder space was available. That, in turn, reduced the power requirements and the size of the required generator.
The advent of encoders/decoders/modulators brought with it the ability to reduce bandwidth requirements by being able to put more data into a smaller space. This made the delivery of stories even less expensive than previously thought possible. The demand of the Television viewing audience to watch 'live' events forced broadcasters to have more trucks, pushing more live video, than ever before.
These smaller trucks equipped with smaller antennas became 'king' for many years. Broadcasters were switching to Ku-Band as the older C-Band trucks were in need of replacement. A new breed of video broker sprang up as the new trucks were less expensive and much easier to maintain and operate. During the 90's, and into the new millennium, a quick look at any newsworthy event would reveal a number of broadcast trucks, both station-owned and broker-based.
As the world's demand for more and more coverage to breaking news events continued to increase, the pressure to provide the live feeds created a situation where Ku- bandwidth was becoming a scarce commodity. Without long-term contracts in place, 'occasional use' bandwidth was in limited supply in many locations across the globe. Satellite operators were reticent to leave empty transponders in their inventory to handle the rush of requests that would occur when a major event happened.
Large agencies had the availability to purchase contracts for bandwidth that they could then share amongst their various locations. Smaller operators were at a disadvantage when it came to buying bandwidth. They needed to be able to acquire the bandwidth they needed, when they needed it and not have to worry that the bigger players had taken all of the available bandwidth. Satellite operators were looking for a way to offer additional bandwidth and meet these demands.
Hughes Network Systems launched Spaceway 3, a Ka-band satellite in 2007. This satellite provided 10 Gbit/s of bandwidth and covered the North America market, which is equivalent to approximately 8 Ku-band Satellites. In 2010, Avanti launched HYLAS 1 over Europe and now offers services to the Middle East, Russia and Australia.Yahsat has taken up the Hughes model and has rolled out Ka offerings in the Middle East & Africa.
October 2011 marked the date of the launch of ViaSat-1, their first Ka-Band satellite. The new satellite was activated in January 2012 and has a total capacity of over 140 Gbit/s. This is more capacity than all the satellites currently serving North America. With its spot beam technology, these Ka satellites are capable of tremendous speed and bandwidth simultaneously.
New dedicated SNG service plans were developed to offer the market an alternative to the standard C-Band and Ku-Band programs. Viasat named their new offering 'Exede' and has actively pursued the video media markets in North America. In the Viasat model, each spot beam is approximately 300km in size and each beam has 450 Mbps of throughput. In Europe, Eutelsat, in partnership with Viasat, offers their Newspotter service to agencies that need 'occasional use' bandwidth.
The Newspotter Ka service can be roughly one-third the cost of similar Ku-Band service. This service is offered on a 'contracted committed volume' basis, where total volume for the year can be contracted, and the actual usage is deducted from the total. The more volume contracted, the less expensive the bandwidth. This allows smaller operators to participate and not just the larger players.
Of course, availability of all of this bandwidth is great, but if you do not have the equipment to access it, you are not benefitting from these advances. C-COM Satellite Systems Inc., the manufacturer of the iNetVu® line of portable and mobile auto deployable satellite antenna systems, was contacted to produce a series of antennas that would operate on these new Ka-Band services. As the beam for the Ka service is so much tighter than the C-Band or Ku-Band services, the antennas are also expected to be smaller. This leaner antenna, given the strict requirements of this new service, demanded extremely accurate and exact pointing requirements.
C-COM's first Ka product was the Ka-75V. This was a unit built specifically for the Viasat Ka offering. It was certified by Eutelsat as the first, fully approved Ka mobile antenna system to meet their stringent requirements. It is configurable to handle all of the transceivers and modems offered by Viasat and Eutelsat. The iNetVu® 7024 ACU has the geo-tables built-in, allowing the operator to simply press one button and the controller sets all of the internal parameters needed to locate and lock onto the satellite. This feature works not only in North America but in Europe as well.
Another unit, the iNetVu 7024 ACU, has the geo-tables built-in. This allows the operator to press a single buttonthe controller sets all of the internal parameters that are needed to locate and lock onto the satellite. This feature works in North America and Europe, as well.
The next offering was a Ka-98H to address the Hughes Ka service. This product was designed specifically to support the HNS supplied Ka service. This antenna system has been designed to work in North America on the Hughes Ka offering, in Europe on the Avanti service and in the Middle East and Africa on the Yahsat service. All models of the transceiver and modem have been tested and are fully operational.
To address a request for a new iDirect Ka offering, C-COM developed the Ka-98G. This unit not only handles the iDirect Ka but also the Gilat Ka service. The Ka-98G has been tested by Avanti in Europe and is in use in the UK and other countries.
A Viasat/Eutelsat version of the 98cm antenna, the Ka-98V has also been developed and is in full certification testing with Eutelsat at the time of the printing of this article. This product will provide better RF performance on the fringe areas of spot beams, and offer better margin for higher bandwidths.
A Fixed Motorized Ka-band antenna (iNetVu FMA-120Ka) has been designed and tested, offering a pole mounted Ka-band antenna solution that provides enough mobility to be moved to a new satellite when needed, by program control. This unit is perfect for remote locations where sending a technician to perform a re-point is simply too expensive. By using remote access to the Controller, the operator can program the new satellite, issue the find command remotely, and the antenna will locate and lock on to the new satellite with no additional intervention required.
C-COM is developing a number of additional new products for the Ka market place. Some are going to be released at Satellite 2013 in Washington DC, while others will be introduced at a later date.
With the roll out of new Ka-Band solutions, companies deploying iNetVu antennas have begun performing their own acceptance tests. At the present time, iNetVu equipped SNG units are deployed in the USA, UK, Germany, Belgium, Netherlands, Poland, Italy, Romania, Spain, Russia, Finland and France. Several other service providers are also in the process of completing testing of these small, extremely powerful mobile antenna systems.