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Ka-Band Ka-Band IP-Over-Satellite Systems Are Becoming an Attractive Alternative to SNG

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Ka-Band Ka-Band IP-Over-Satellite Systems Are Becoming an Attractive Alternative to SNG TECHNOLOGY IN TRANSITION NEW PRODUCTS & REVIEWS Ka-band Ka-band IP-over-satellite systems are becoming an attractive alternative to SNG. BY STUART BROWN ews remains a central introduction of 4G has alleviated this 38 times the data capacity of a com- genre for broadcasters, a little, but as general uptake of 4G in- parable Ku-band satellite. The extra and as new markets and creases, the problem of network con- capacity not only reduces costs, but new delivery platforms gestion is likely to re-emerge. also it minimizes contention, the Nemerge, broadcasters are expected Another solution rapidly gaining number of people sharing access to to provide 24/7 coverage for roll- traction in Europe is the use of Ka- the system and thus competing for ing news channels and increasingly band IP-over-satellite systems. Intro- its resources. This is important when sophisticated websites. In an era of streaming video. tight budgetary control, that means controlling deployment costs while Antenna size responding ever faster. The gain of a dish antenna is pro- Traditional methods for establish- portional to the frequency being used. ing live links — such as point-to-point At the high frequencies of Ka-band, microwave and satellite newsgather- you can use a smaller dish to get an ing (SNG) — continue to dominate. equivalent power output up to the There are, though, newer methods satellite. It also means the RF ampli- based on IP delivery, and we are see- fier requirements are reduced. ing these beginning to get a foothold This all combines to significantly in the contribution market. reduce the size, weight and power Using an IP platform has a number requirements of the terminal, mean- of benefits, including: ing it can be transported in a regular • Cost: Because IP systems are used by car or flown as checked-in baggage. pretty much everyone these days, hard- Carrying the equipment rather than Power consumption of a Ka-band ware and connectivity are inexpensive system is in the range of 60W to 70W, waiting for it to be shipped makes for and getting cheaper by the day. so a journalist could carry it to a news faster deployment. • Universality: IP is a universal stan- location, rig it in a rental car and run it dard for transmitting data around the from the car battery. Line-up world, greatly simplifying operations duced to provide high-speed Internet Finding the correct satellite and from foreign countries. connectivity to remote communi- then optimizing the antenna align- • Bi-directionality: IP readily supports ties, these systems can also be used ment is traditionally a skilled job and IFB and reverse communications. to provide HD broadcast quality live requires an engineer with complex • Enhanced communications: An IP paths, plus Internet and IT facilities, and expensive equipment such as a platform can give journalists access to at a fraction of the cost of “regular” spectrum analyzer. As the latest Ka- increasingly sophisticated newsroom Ku-band SNG terminals. band systems are designed for home IT systems and the Internet. installation by unskilled personnel, Today the most common IP plat- Frequency re-use much of the alignment process has form is the range of 3G/4G bonding Ka-band operates at extremely high been considerably simplified by the systems, which use multiple cell phone frequencies — in the 30GHz range. system design. data channels to send and receive ma- This enables the satellite spot beams In Europe, Eutelsat provides a free terial. These are quick to set up, so to be much smaller than those typical iPhone app for locating its main Ka- they often work well as a first response of Ku-band. band satellite, KA-SAT; holding the solution. However, they can be unreli- In turn, this enables the frequencies phone up to the sky shows the user able, particularly at large events where for each beam to be re-used in differ- exactly where the satellite is located. the systems are competing for band- ent spot beams without risk of inter- The user simply sets the dish elevation width with the general public. Bit rates ference. This significantly increases to the displayed figure and points to are typically below those normally the capacity of the satellite. the area of sky indicated. The trans- considered for even SD quality. The The latest Ka-band satellites have ceiver then emits a tone to guide the 46 broadcastengineering.com | February 2013 TECHNOLOGY IN TRANSITION NEW PRODUCTS & REVIEWS final optimization of elevation and live to air. Major broadcasters are taking advan- azimuth. Ka-band services use circu- The antenna will be in the 0.6m to tage of the agility, flexibility and cost lar polarization, so there are no issues 1.0m range. A 0.75m dish will give savings that IP over satellite delivers. with cross-polarization associated the required performance in most One broadcaster covered the Greek with traditional Ku-band systems. conditions. Most of the major manu- general elections using a single 70cm facturers have Ka-band flyaway and Ka-band antenna clamped to a railing Bookings vehicle mount antennas of this size on the roof of the journalists’ hotel. Once the terminal is correctly in their product ranges. This links to Using the bi-directional IP platform, pointed at the satellite, it automati- the transceiver, which will probably they were able to provides imultane- cally logs on to the system and, in a be 3W to 4W. It will mount directly ous live reports for domestic and in- matter of a few minutes, is ready to be on the antenna and connect to the ternational television bulletins; off-air used. Initially, it gives a low-bit-rate data modem by L-band RF cables, al- feeds of competitor broadcasters and connection to the Internet, allowing though some systems now use a single local Greek TV; FTP transfers of ed- access to a booking portal for reserv- standard coax cable. ited packages; live radio reports; FTP ing higher bit rates. The IP-over-satellite modem will transfers of edited radio packages; full The traditional downside of Ka- depend on the choice of satellite access to the newsroom IT system; and band has always been its susceptibility system. In addition to converting IP Web browsing and e-mail. to rain fade. This is because, as a gen- data to satellite RF, it will also supply All this was accomplished using a eral rule, the higher the frequency of power to the transceiver. The video transceiver and modem combina- an RF signal, the more it is absorbed data, in turn, comes from an IP video tion, which cost $500. It makes an at- by rain. The latest systems compen- encoder, again widely established and tractive alternative to SNG! BE sate for this by running with signifi- proven technology. Stuart Brown is Broadcast Systems cant spare capacity in clear sky condi- The complete system is likely to Director of Cobham. tions. In severe rain, the system will weigh less than 44lb and pack into a automatically drop to a more robust single case, meaning it would not be modulation scheme. It means the a serious problem to take it as bag- user will notice a drop in available bit gage on a commercial flight. Power The following are available on the Broadcast Engineering website: rate, but should still remain on-air. consumption will be in the range of Let’s look, then, at a typical system 60W to 70W, so the journalist could • A tutorial on modulation designed for HD newsgathering. The carry the system to a news location, technologies, from ASTC, OFDM, minimum requirement should be for rig it in a rental car and run it from QAM to DVB data rates of around 9Mb/s upload the vehicle battery. • The cloud and connectivity and 20Mb/s download, which gives Most important, all this technology • Is the cloud really as green or comfortable headroom even when is available today and proven in use. cost-friendly as widely thought? February 2013 | broadcastengineering.com 47.
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