Earth Stations: Faster, Cheaper, Better
By Peter J. Brown
Earth stations no longer fit into a neat, narrowly defined category. No, VSAT vendors are not threatened by any attempt to expand the definition of earth station, and the Standard A earth station still sits at the top of the scale. However, everything in between is subject to revision as the accelerating demand for two-way solutions via satellite is compelling the industry to redraw the map. In the process, the accepted boundaries which once separated products into distinct categories are becoming more difficult to maintain.
When it comes to earth stations, the satellite industry is addressing the needs of both the consumer and the professional or enterprise markets simultaneously. Not only is the industry willing and able to sacrifice spectral efficiency in order to reduce costs for consumer terminals, but it is also devising better ways to implement Bandwidth On Demand (BOD) in multi-user enterprise environments,” says Shaul Laufer, president of Israel-based Shiron Satellite Communications Ltd.
Internet Protocol (IP) is the dominant force. With IP come new twists to the old point-to-multipoint grid. Things such as asynchronous data delivery including faster than real- time delivery to caching stations, and strict adherence to service level agreement (SLA) parameters are becoming more commonplace. Hybrid satellite/fixed wireless access (FWA) and wireless local loop (WLL) solutions represent another noteworthy trend.
“The days when a VSAT simply had to set up and tear down 6 kbps voice circuits are not over entirely, but the emphasis now is on IP traffic which involves new traffic profiles, and the pursuit of optimization where real-time protocols in particular need special attention,” says Michael Rudeen, director of program development and systems engineering at Phoenix-based Radyne ComStream.
“Multiple access return channels, and the fact we can integrate the IP stack and routing equipment together into one piece of equipment, thereby eliminating the need for an external router, means that we can open up the market to more users,” he adds.
Whereas in the past, earth stations were large international gateways that carried a percentage of the total network traffic, earth stations today are often small VSAT terminals, whose strength is their ability to share the available satellite resources with other terminals in the same network, according to Don Osborne, senior vice president and general manager at Montreal-based EMS Technologies Inc.s’ Space and Technology Group.
“This has resulted in a trend towards lowering the emphasis put on the terminal itself, and increasing the emphasis on the network management and bandwidth sharing software,” says Osborne. “By a twist of circumstances, the new generation broadband Ka-band Satellite Interactive Terminals (SITs) are renewing the emphasis on the terminal. This is due to the need to drive down terminal costs to the consumer level. This in turn can produce networks large enough to easily amortize any sophistication in the network management or control facilities.”
Radyne ComStream is just one example of a satellite equipment vendor that has allowed its product lineup–earth stations including its DVB-compliant IPSat SCPC and TDMA solutions, broadband modems and multi-purpose DBR series IRDs–to synchronize itself seamlessly to the overall shift to IP-based services. A customer can either select the IPSat delivery system as a standalone product, or it can tap Radyne ComStream for a complete end-to-end system solution.
At the same time, this company is similar to so many others in this earth station space in terms of its multiple roles. It can be a partner, customer or a competitor, depending upon the specific circumstances in question.
So Many Choices
Let’s face it, much smaller earth stations are popping up everywhere, including new units in beta test phase at Betzdorf, Luxembourg-based SES Multimedia, for example, which are capable of receiving up to 38 Mbps, and beaming traffic back at 2 Mbps.
Despite a lengthy track record when it comes to cross-strapping satellites with C-band and Ku-band, there is a tendency in the industry these days to lock in a certain frequency limitation for the business model in question as if one is either going to proceed with Ku-band or Ka-band over the next few years.
Thankfully, SES Multimedia is one of the few industry heavyweights which has embraced the Ku-/Ka-band model with much enthusiasm. SES Multimedia’s Broadband Interactive (BBI) Group has now reached the beta testing phase of its multi-year project, and it has turned to EMS Technologies, and to Raytheon Satellite Access Systems Group in Marlborough, MA, for its SITs.
“EMS and Raytheon together represent a strong combination of two different SIT vendors. They prove that interoperability with a single EMS Ka-band hub using a full open- standards based Digital Video Broadcast-Return Channel System (DVB-RCS) is both feasible and practical,” says Robert Feierbach, BBI business director. “We currently have beta customers on our BBI system, transmitting at up to 2 Mbps on the return link to satellite, and SES is scheduled to begin commercial service by mid-year 2001.”
With the successful demonstration of Ku-band outbound data at speeds up to 38 Mbps, along with inbound or return channel speeds at 144 kbps, 384 kbps and 2 Mbps using EMS terminals, Feierbach indicates that in some instances the Ka-band return link proved to be even more sustainable than the Ku-band feed.
“With DVB-RCS, the link margin is really quite good. We lost the Ku-band signal in heavy rain only to discover the SIT variable power controls were able to ensure that the return channel held up in the same adverse weather conditions,” says Feierbach.
“On the return channel, we can carry live MPEG-1 files in full screen with quasi-broadcast quality. Of course, while the 38 Mbps Ku-band outbound feed is suitable for most high-end servers, it far exceeds the ceiling for the average PC which can only process IP data at approximately 6 to 8 Mbps,” Feierbach adds.
Osborne indicates that in all respects, the transmission system is fully operational on an end-to-end basis. Satellite loop tests have been ongoing for over nine months in both Ku-/Ku-band in Canada, and Ka-/Ku-band in Europe. A number of prototype and pre-production terminals have been deployed and are in operation at beta customer sites in the United Kingdom and Spain. EMS has delivered its first commercial return link platform to ND Satcom facilities, where it will be integrated with broadcast (forward link) and network management facilities prior to delivery to SES in Luxembourg.
Friedrichshafen, Germany-based ND Satcom, formally Nortel DASA Satcom and now under different ownership, is responsible for the network management system, the traffic manager, the local hub manager and the integration with the return link and forward link sub-systems, according to Osborne.
Challenges that remain are the completion of the hub to its full level of functionality and capacity in 3Q 2001, and the deployment of production terminals this summer. James Rooney, director of Raytheon’s Satellite Access Systems Group, describes Raytheon’s participation in the commercial broadband satellite terminal marketplace as a natural progression for Raytheon.
“With our many years of involvement in U.S. DoD Milstar at Extra High Frequency (EHF or 20 GHz receive and 44 GHz transmit), we have developed considerable expertise in the development and manufacturing of broadband terminals which engage in very fast frequency hopping (FDMA), and time division multiplexing (TDMA),” says Rooney. “As we evolve from the military to the commercial marketplace, we are stripping away some of the robustness of the military terminals in order to focus on ultra low-cost, high-volume production.”
Raytheon is currently manufacturing 500 DVB-RCS terminals. These beta units will be field-tested this summer–with DVB-RCS under construction for SES Multimedia, according to Rooney. Among other things, the design of the Satellite Multimedia Delivery System (SMDS) with its integrated 1 to 10-watt SSPA-LNA, eliminates the possibility that someone could look directly into the feed. Service providers need to make sure their customer’s safety is adequately addressed. In addition, using a concentric dual band feed with a dual shaped offset Gregorian reflector made sense to Raytheon for performance and installation reasons, and the added safety benefit is just icing on the cake.
“Refining the product, and achieving cost-savings in the installation is also important, especially when the Ka-band beam is so narrow. We designed our Beamtrac 2100 automatic positioning system to assist installers in aligning the antenna without the need for hub interaction, and our co-boresight approach allows them to do Ka- and Ku- pointing simultaneously,” Rooney says.
Faster, Cheaper, Better And Always-On
Incorporating the right features to manage satellite resources efficiently, while allowing simultaneous multiple access with time zone shifting and application sharing is essential. For example, Shiron’s InterSKY solution is a two-way broadband Internet access via satellite system which uses a star configuration. It incorporates unique Demand Assigned Multiple Access (DAMA) and BOD with power and frequency controls, while the users at a remote LAN assume their connecting terminal is in always-on mode. InterSKY reduces the operational costs for the service providers significantly. According to Laufer, the typical saving of satellite spectrum assigned to return channels is 50 to 60 percent.
“The InterSKY BOD software measures the traffic at the remote sites, and dynamically assigns bandwidth to each remote site, according to the actual instantaneous needs,” says Laufer. “The committed information rate (CIR) and link budget are all taken into account. The BOD software manages the remote site power levels to ensure that transmissions are undertaken with the exact power level necessary to meet the terms of the designated SLA.”
Having the ability to adhere firmly to service level agreements may attract customers, but having a longer-term strategy means going the extra mile from the moment the earth station component in question begins to take shape.
“DSL and cable modems are having a profound effect on the satellite industry as a whole. As manufacturers we have to do things much more efficiently,” says John Sciberras, vice president of marketing for North Carolina-based TriPoint Global, which includes the Prodelin line of antennas, and the new modular solid state power amplifier (SSPA) known as Modumax from VertexRSI.
“New customers are popping up who do not know what they want. They see a market opportunity, but they do not know how to get there. There is a much greater emphasis on complete solutions with fixed wireless interfaces,” he adds.
While the emphasis is on standards with off-the-shelf platforms, Sciberras indicates that once you look beneath the surface, things are not so uniform or consistent. “Take DVB for example. I think DVB is still trying to sort itself out. Some customers use pure DVB including DVB-RCS, others broadcast DVB but use another return channel format, while others use no DVB whatsoever,” Sciberras says. “No single technique dominates.”
“When you take a macro perspective of the market, it is much more than some sort of a simple virtual private network (VPN) concept unfolding. As manufacturers, we have to be spun up on all these different approaches such as how customers stack their data, do modulation or what specialized return paths they employ,” Sciberras adds.
With its ModuMAX Solid State Power Amplifier (SSPA), NetMac control software and the 1.8-meter lineup of Quick Deploy antennas, the emphasis at TriPoint Global is on earth station modularity, rapid deployment and rapid servicing including hot swapability in the case of the Modumax SSPA. “Our customers are becoming more carrier-like with more data going to more ISPs in the process,” Sciberras says.
Between The Gateway And The Vsat
Hauppauge, NY-based L-3 Communications Group Corporate Vice President Stuart Mackiernan who oversees L-3 Satellite Networks Division–formerly LNR / STS–believes the demand for earth stations that sit somewhere between the gateways and the VSATs will be increasing.
According to Mackiernan, the very large earth station market is going through a slowdown as everyone awaits the next generation of domestic and international satellites, among other things. “The industry as a whole remains enthusiastic about IP transport over satellite. We see opportunities for two-stage ISP rollouts involving transportable earth stations for rapid deployment followed immediately thereafter with a permanent installation as very attractive,” says Mackiernan.
With the recent acquisition of the ISAT frame relay-based trunking system from Gilat, Satellite Networks is not only reinforcing its IP transport via satellite capabilities, but it is also setting the stage for a wireless play as Satellite Networks unites ISAT with its Prime Wave FWA platform.
In terms of what is hot in the new earth station domain, Satellite Networks is working with United Pan-Europe Communications N.V. (UPC), one of the largest cable service providers in Europe, on two major facilities in Amsterdam and Helmund in the Netherlands.
“This is the first true multimedia distribution network. It extends throughout Europe, and it is a multi-phase project. In addition to the two large facilities in the Netherlands, we have already installed three spoke terminals at cable headends, and we have been contracted to install a total of 17,” says William P. Kinsella, chief technical officer at Satellite Networks. “The network is designed for voice over IP (VoIP) and Internet traffic to flow back into Amsterdam via satellite where it is tied into UPC’s vast fiber network known as AORTA.”
UPC is the first customer for Satellite Networks’ GMACS-32 network management software. It is installed at the huge UPC Digital Media Center outside Amsterdam where digital content is layered with multiple language tracks and subtitles, and then distributed via satellite. UPC uses faster-than-real-time distribution in order to reduce the cost of satellite time on Telstar 12, and to maximize the use of video servers in UPC’s distributed caching environment. UPC’s Chello broadband unit oversees AORTA, which stands for “Always On Ready To Access.”
A Complete Ip Network Solution Is Needed
Not only is everything converging in IP format, but there is also a noticeable trend that involves the creation of new media centers that look a lot like data centers. At least that is the view from Hauppauge, NY-based Globecomm Systems Inc. where David Hershberg, chairman and CEO, believes the sun has set on the very large earth station market, at least for the foreseeable future. He uses the Thailand-based BEC Multi-Media Co. Ltd.’s multimedia data center–BEC Multi-Media recently selected GSI to design, engineer, support and install this facility–as a good example of what constitutes a state-of-the-art IP-based content management and distribution system.
“With deregulation in the marketplace, it is not a great market now for large gateways. It will take a year or two for any new customers to emerge in the Intelsat Standard ‘A’ environment,” says Hershberg. “Besides, many of the large carriers in the United States and elsewhere, for example, already own four or five large earth stations.”
The noticeable shift to IP–as well as VoIP–is driving overseas demand for smaller terminals in general in the 3.8, 4.6 and 5.5-meter range. “Transportables and IP-based terminals with data and IP on the same carrier are where the market is going. Along with wireless WLL interface capabilities, what customers want is a complete network solution,” Hershberg says.
Globecomm and its subsidiary, NetSat Express, are pursuing clients in overseas markets exclusively with numerous projects underway. The possible provision of WLL connectivity has been added to the Globecomm product and services menu recently.
“Our value proposition is a complete solution. We provide everything including routers and servers, and we integrate them into the network,” Hershberg says. “The money is just not in RF terminals any more. In an end-to-end satcom service solution, the earth station portion might account for as little as 20 percent of the total price tag.”
For Telefonica Data S.A.’s Para Network in Latin America, for example, where IP traffic flows as two 45 Mbps streams via twin 16-QAM carriers combined in a single 36 MHz Hispasat transponder, Globecomm tapped five different teleport operators along with a team of vendors including Cisco Systems, Vertex/RSI, Andrew, CPI, Xicom, Miteq and Newtec.
“This international Internet distribution and access network operates off a 9-meter Ku-band dish here in New York. We put all of this in place in just four months, using up to 9-meter Ku-band dishes at the remote sites to provide lots of margin. When I say end-to-end solution here, I mean everything,” Hershberg says. That list includes the entire regulatory and licensing apparatus, network and earth station design and implementation, operations and maintenance of the network from their Long Island Network Operations Center (NOC), logistics support and, legal and tariff framework.
Turnkey Gateway Systems: Taking Full Advantage of Automation
With CO-based WildBlue Communications Inc. rushing to fill the Ka-band broadband gap over North America starting in the United States early next year with low-cost two-way satellite systems, the goal is to install twin Ka-band antennas in six gateways nationwide by the end of this year. WildBlue is turning to Orland Park, IL-based Andrew Corp. to design and install these modular, unmanned facilities.
The primary site consists of a 20 x 30-foot concrete shelter which is linked to a 5.6-meter antenna. It contains approximately 21 racks of equipment including ViaSat modems. Approximately 20 or 30 kilometers away sits the “diversity” site–providing spatial diversity–which provides redundancy in the event of adverse weather conditions at the primary site.
“We are taking advantage of automation with all the SNMP-based monitoring and control (M&C) equipment tied back to operators at the NOC who are using an advanced graphical user interface (GUI),” says Joe Ducey, WildBlue’s director of gateway development. “System wide network management will occur at the NOC, while each gateway will also be capable of monitoring all of its own local operations automatically.”
“In the area of control systems, Ethernet interfaces and SNMP protocols are pretty widely accepted as part of the trend involving open architecture systems. The antenna control systems and the new generation of IRDs tend to be Open System Interface (OSI)-controlled) instead of serial RS-232. This represents a vast improvement over the situation in the past where you had to look up the interface for each device in the manual,” says Anthony Campbell, business unit manager at Andrew Corp.’s satellite products/systems.
Campbell sees an automated environment for broadband satellite services requiring two additional distinct control elements in the network architecture on top of satellite control. These involve M&C of the hardware and traffic including Quality of Service (QoS) monitoring synchronized to M&C of the remote sites where temporal and frequency channel assignments are in play.
“These control elements may or may not collocate in a single layer,” says Campbell. Campbell is making the point that the issue of how to best address the control of the uplink, network and subscriber terminals in a dynamic environment is just one of many complex issues that lends itself to the sort of turnkey solution that WildBlue has embraced.
“There is a temptation to bite off bits and pieces. With critical data and two-way traffic flowing over a network sustained by automated or unmanned gateways–similar to the model that WildBlue is adopting–it is important for operators to actually achieve the full range of cost advantages and not to do so simply on paper,” Campbell says.
Pushing Hybrid Satellite / Wireless Earth Stations
Along with a few other companies mentioned earlier, Greenwich, CT-based Alpha- Star International is also pursuing a hybrid satellite/wireless Internet access strategy. It launched SkyCrossing.net. last August. The SkyCrossing.net service comes in three flavors. One is a hybrid architecture integrating satellite broadband for IP backbone connectivity, and local wireless access–both fixed and mobile–for the last mile solution. SkyCrossing also offers a direct two-way satellite service for the multi-dwelling unit (MDU) and SOHO markets. It is currently using space segment on GE Americom GE 5 and GE 6 to cover all of North America, the Caribbean and parts of Latin America.
“Our hybrid model integrates the best of satellite broadband with the best of local wireless. The signal is delivered by satellite to a two-way satellite dish at a local wireless gateway mounted at a wireless tower or on a rooftop. From the wireless gateway, the signal is transmitted back and fourth via radio waves to a radio antenna at the subscribers residence,” says AlphaStar International CEO Mahmoud Wahba. “Wireless gateways also allow insertion of local content cheaply and quickly unlike DTH.”
Wahba emphasizes that although this entails a direct line-of-sight delivery platform, this is not an MMDS solution. As far as the components at the local remote station or gateway, Wahba is not prepared to divulge all the details about what lies between the two-way satellite dish and the wireless base antenna. However, he does describe a 4RU modular solution that includes Cisco Systems routers, and a caching engine from Infolibria.
Wahba sees this as the ideal answer for unserved areas, and under-served Internet users. Not only is it designed for self-installation, but the subscriber does not interact directly with the satellite as one would with DTH; rather interaction is with the local wireless gateway, which includes a cache that is constantly updated via satellite.
“With the most popular 1,000 Web sites cached at the local wireless gateway, this greatly reduces the need for any direct interaction with the satellite by 50 percent or better. The hybrid model also allows for the use of shared BOD among local wireless gateways, which can save an additional 25 percent of the cost of space segment,” says Wahba. “In short, the hybrid model offers substantial savings in the cost of the space segment when compared to the DTH model.”
Dish Sizes Shrinking And Growing
Antennas are going through a rather odd metamorphosis. Much has been said about the shrinking dish size, but the antenna experts we spoke with tell a slightly different story. “Antenna sizes are actually growing with the advent of digital carriers. The size is increasing not for gain reasons, but in order to ensure selectivity–to reject unwanted signals from adjacent satellites,” says Tom Christy, president of St. Cloud, FL-based Comtech Antenna Systems Inc. “Due to this more hostile digital environment, we have seen an increased demand for our 3.8-meter antenna.”
With more and more carriers being squeezed into the same amount of satellite bandwidth, Christy does not expect to see this trend soon ending. Comtech has addressed the need for lower-cost mobile antenna systems by providing quick deployables in addition to its standard flyaway and transportable products.
“Quick deployables and flyaways have seen the most dramatic growth in the past couple of years. Not everyone needs a flyaway that is air checkable, so the quick deployables are ideal for a lot of rapid response scenarios. They are also less expensive than flyaways,” Christy says.
Steve Pokornicki, account manager at Satellite Export & Engineering Inc. (SEE) in Albion, MI, does not see the digital carrier-related side lobe issue adversely impacting on the demand for multi-feed antennas. He estimates that perhaps 15 percent of his company’s Patriot brand antenna sales involve multi-feed antennas which are given away by satellite operators such as PanAmSat, GE Americom, and Loral, to name a few.
Pokornicki indicates that demand for Patriot 3.8-meter and 4.5-meter antennas, with multi-beam feedhorns and phase stable LNBs, is quite strong. The same is true for the company’s line of small aperture units in the .76-meter, .9-meter, 1-meter and 1.2-meter offsets.
“These are not flyaways, but receive-only units for customers such as DBS service providers, and for music distribution networks such as DMX, and Musix. Our focus is now on Ka- band, and on obtaining Intelsat uplink approval for our two-way antennas,” Pokornicki says. “It can take up to six months for us to obtain this Intelsat certification which ensures that when private networks are installed for large enterprise customers in particular, all the antennas in the network can talk to each other.”
The export market for VSAT antennas is growing, and SEE is responding by opening offices in Argentina and Portugal, and it plans to open a pan-Asian distribution center in Australia. While the international market is expanding, it is not outpacing the domestic market, according to Pokornicki.
In addition, signal degradation research involving so-called wet antenna effects in the Ka-band environment is ongoing. This phenomenon only compounds the challenge for the network design team. For example, Beatriz Soares at Andrew Corp. has been evaluating the performance of 1-meter aluminum and composite reflectors with an emphasis on the exploring the application of hydrophobic treatments to aluminum reflectors.
Using Finite Bandwidth To Do The Job Right
As our economy cools and as the telecom industry is nervously bracing for further consolidation, there is talk of restructuring and the presence of fiber overcapacity on the ground. Will it unwind a few business plans? You can bet on that.
Meanwhile, the ground segment in the satellite industry is rapidly evolving, and preparing its earth stations to meet a variety of needs, while constantly stressing the use of bandwidth in the most efficient way possible. This is in striking contrast to the terrestrial side of the equation where bandwidth in abundance gets thrown at a particular business model, and where bandwidth seems to exist in infinite supply.
The lean and mean IP-driven strategy employed by most earth station companies today will no doubt woo enterprise customers in particular who want affordability, flexibility, reliability and scalability all in one robust platform. The satellite-based content and data distribution model is quite attractive, and you can be sure that many satellite professionals are going to devote considerable energy to make sure it stays that way.
Peter J. Brown is Via Satellite’s Senior Multimedia Editor. He lives on Mount Desert Island, ME