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Web Exclusive: Satellite and Terrestrial Wireless: A Powerful Pairing

By | October 10, 2001

      Peter J. Brown

      Hybrid wireless/satellite (HWS) networks can be deployed anywhere. Using an antenna on a tower or a building to create a secondary terrestrial wireless footprint within a satellite footprint may seem a bit redundant. However, for a variety of reasons, service providers have found that HWS is a combined platform that can make a lot of sense in cities as large as Lagos, Nigeria, and in tiny remote villages in northern Canada and Alaska.

      Although many of the HWS vendors have their roots in the traditional VSAT / wireless local loop (WLL) sector, they have adapted quickly to a lot of new developments in terms of both local area networking (LAN) and wide area networking (WAN) options. Beyond the rural telephony models that seemed to constitute the core of the VSAT / WLL offering in the past, readers will soon see that HWS spans the entire range of wireless services from thin route telephony to the emerging line of broadband wireless Ethernet solutions including the expanding selection of Wi-Fi hardware which uses the IEEE 802.11b standard.

      Still, many in the satellite industry see this as little more than a tight niche market with a limited future. Others strongly disagree, and are pushing hard to increase awareness of the whole HWS concept.

      “This emphasis on the need for an HWS solution is bouncing back after losing a bit of momentum,” says Catherine De Peuter, manager of universal service development at Intelsat. “This is tied to the broader issue of universal access on a global basis which was considered a much higher priority about two years ago, but then it slipped down on the list. Now, it is rebounding again.”

      Rapidly dropping VSAT prices, growing demand for more than basic telephony services and a lack of uniform wireless standards have kept wireless base station unit costs high. These have all reduced the momentum behind any large scale effort to develop the HWS sector, according to Ramesh Ramaswamy, senior director of business development for the Middle East/Africa region in the International Division of Hughes Network Systems (HNS) in Germantown, MD.

      “Why worry about such things as cell planning in areas with very low subscriber density? It would be better to just put in a VSAT which is cheaper to maintain,” says Ramaswamy. “The business case for hybrid fixed wireless systems is becoming harder to justify as VSAT costs drop much quicker than expected. VSAT systems are an ideal solution to provide a broadband overlay to existing WLL systems.”

      When it comes to Global System Mobile (GSM) networks, Ramaswamy is quite enthusiastic.

      “VSAT systems provide a natural fit to extend GSM services rapidly into rural areas. You can connect a rural GSM base station to an urban base station controller with a VSAT link, while the GSM switch allows local connectivity,” Ramaswamy says. “With GSM, you see the advantages of standards along with the cost benefits of volume production for the end user equipment.”

      Fabrice Langreney, vice president of operations at VA-based SkyOnline, believes that HWS suffers because VSAT vendors are focusing on how best to spur box sales. In addition, HWS is viewed basically as a temporary solution awaiting a more robust replacement.

      “Service providers still need this type of solution, but a broader industrywide effort is required to move HWS solutions ahead. A major impediment to this sort of hybrid solution has been the lack of international coordination on wireless frequencies. For example, the 2.4 MHz ISM-Industrial, Scientific, Medical- band or the Digital European Cordless Telephone (DECT) band is available in Mexico, but not everywhere in Latin America,” Langreney says.

      The Right Mix

      How does the wireless sector view HWS networking? The Wireless Ethernet Compatibility Alliance (WECA) has been created to promote Wi-Fi, the IEEE 802.11b wireless Ethernet standard that operates in the 2.4 GHz range. Wi-Fi is one option. Another is the wireless LAN solution known as Bluetooth.

      Amer Hassan is a wireless architect at Microsoft Corp. He chairs WECA’s marketing committee and sits on the WECA board of directors. “The timing is perfect. This is all about the right mix of technologies. The success of the satellite industry might well depend upon how the industry complements its solution with a wireless LAN Ethernet platform,” Hassan says.

      On the Microsoft campus, for example, a Wi-Fi system with over 20,000 users is currently running at a shared user rate of 7 Mbps. Hassan indicates that a next generation Wi-Fi solution will run at a rate above 20 Mbps.

      “Wireless LAN is going to be at the core of numerous businesses. At the same time, broadband Ku-band or Ka-band cannot penetrate the building. The key to the future lies in a seamless layering of satellite broadband, 3G mobile wireless, and Wi-Fi,” says Hassan. “Enterprises know that fiber only reaches so far, and that is where satellite plays such an important role on the WAN side. For multiple channel, high bandwidth networking, satellite and Wi-Fi will be hard to beat.”

      From the standpoint of flexibility and scalability, HWS can offer real advantages as well.

      “A lot will depend on the amount of customers that are connected to the existing network. If a satellite terminal has a large customer base connected to it then a second satellite terminal is then placed at a new location to provide coverage that overlaps the first terminal, thus providing a larger service area,” says Jesse Hindemith, president of San Diego-based AdvancedTech Communications Inc.

      “Now customers on the first system can be connected to the second system if the microwave signal is stronger pointing at that site. For a satellite site that has a small customer base, the cost effective approach would be to connect microwave transmitters back-to-back to increase the radius of the coverage,” he adds.

      AdvancedTech has a project under way using capacity on GE 4, and a Tachyon Access Point (TAP) consisting of a .95 meter antenna, a 2 Watt SSPA and transceiver, and an indoor unit (IDU) with an Ethernet (RJ 45) port.

      “The indoor unit is then connected to a Breezecom wireless system operating at 2.4 Ghz unlicensed frequency. The indoor Breezecom unit has several slots that occupy transceiver units which are then connected to multiple heliax cables that travel up a radio antenna tower,” says Hindemith.

      Another HWS implementation involves a Harmonic Data VSAT hub linked to a 1.2 meter VSAT antenna with 1 Watt SSPA and transceiver and an IDU with an Ethernet connection.

      “The VSAT is mounted to a mobile shelter that can be sent anywhere that Satmex 5 can radiate a signal. The shelter has Aironet wireless equipment which operates at 2.4 Ghz unlicensed frequency,” says Hindemith. “In the shelter, the Aironet hub is connected to a LAN which then connects to multiple computers within the shelter. The VSAT system and the shelter can be located miles apart, the network can be set up to handle multiple shelters over a 10 mile radius.”

      HWS Is Real And Robust

      Many service providers and vendors have embraced HWS networks as the optimal solution given all the variables with which they have to deal. In Canada’s Northwest Territories, for example, one encounters an HWS strategy in high gear using Telesat’s Anik capacity.

      “We have a ton of cases of high speed wireless LANs connected to our private satellite network in many remote northern communities,” says Jeff Philipp, president of Yellowknife-based SSI Micro. “Our network uses 4.5 meter antennas, and 80 Watt SSPA’s connected in a full mesh design with dynamic bandwidth allocation all over Frame Relay using the Comsat (now Viasat) Linkway platform. This network covers nine sites across the North. In total, it connects over four million square kilometers.”

      Philipp describes a mix of wireless infrastructures consisting of older Lucent 915 MHz gear running at 2 Mbps which was installed three or four years ago, along with newer Lucent Orinoco Wi-Fi or 2.4 GHz equipment running at 11 Mbps.

      Among the nine locations in the North where SSI Micro has deployed this HWS solution are Iqaluit on Baffin Island, which is the capital of the new Canadian province of Nunavut, Rankin Inlet, Cambridge Bay, Tuloyoak, and Hay River.

      Moe Abutaleb, president of MD-based Innovative Communications Technologies Inc. (ICTI)-a division of Advanced Remote Communications Solutions-has overseen the deployment of HWS networks in Eastern Europe and Russia since the mid-1990’s. ICTI specializes in spectrum optimization technologies and techniques, turnkey networks for startup carriers, and overlays for PTT’s.

      “In developing markets, a large percentage of people do not have simple telephony service, but they have access to local TV programs. Providing wireless connectivity to an Internet portal in these settings makes much more sense than double hopping to a VSAT,” says Abutaleb. “As the world gets more data savvy, the most efficient solution is to use inexpensive wireless technology to seamlessly connect to the local ISP.”

      For ICTI, work on HWS solutions spanned the Vostok region of southern Russia in 1996 and 1997 when ICTI deployed a solution involving the trunking via satellite of local cellular traffic to a remote cellular switch in Moscow. This network used Intelsat 602 to move Analog Mobile Phone Service (AMPS) traffic off approximately 20 cell sites.

      In Siberia, ICTI set up a network of fully redundant earth stations using Vertex 7.2-meter C-band dishes communicating with Intelsat and Intersputnik satellites to link Moscow to 25 commercial capitals. All traffic for commercial users was trunked via a combination of wireline and wireless technologies to the earth station in each city, and then interconnected with the Moscow gateway station via satellite.

      “Maintaining the stability of this ISDN satcom network in the Siberian winter was pretty tricky. In some cities, there is no fiber or copper connection readily available or accessible so we had to link our earth stations to the central offices using microwave links, point-to-multipoint trunking and other wireless technologies,” says Abutaleb. “We also had to feed call data records into a billing engine integrated with our proprietary management system in Moscow in order to generate invoices every month.”

      For Prague-based Czechnet, ICTI designed a solution that local loops traffic through a single node. The traffic is then sent via ECI Telecom DCME (Digital Circuit Multiplication Equipment) to Monaco using dual T-1’s on a Eutelsat satellite with the voice traffic compressed at 16 kbps. The Czechnet service uses a proprietary management system from ICTI along with fully redundant DCME nodes, Comstream modems, and SSE radios, according to Abutaleb.

      “Interconnecting in Prague has been a big challenge. Czechnet was initially going after big hotels and business centers,” says Abutaleb. “We created a billing interface in Monaco and ran our own network management system as well. Elsewhere, we have gone so far as to develop custom interfaces between satellite and wireless systems to achieve seamless connectivity between HWS networks when necessary.”

      Coverage of developments in a small remote community in Alaska 225 miles southeast of Anchorage with a combined total of 400 people and just 75 residential and business Internet accounts seems out of place in a Web site where the satellite companies featured often tend to count Internet users by the millions. However, in this case, the local ISP- McGrathAlaska.Net-is an HWS powerhouse.

      In McGrath, the ISP is turning a profit, the network administrator is a 16-year-old, and a community that was almost totally computer illiterate two years ago now has a PC in almost every home. A Frame Relay satellite link via AT&T Alascom provides the backhaul, while Bellevue, WA-based Spectrum Wireless provides the wireless IP router, and three wireless base stations or access points. Customers receiving the service must mount a 2-foot by 3-foot semi-parabolic grid type antenna on their homes which must have line of sight shot at the source of the 2.4 GHz signal.

      “Forty of our accounts are wireless, and they pay $32 per month for a service that runs somewhere between 80 kbps or 85 kbps on up to 256 kbps when the traffic is light,” says Ernie Baumgartner, general manager of McGrathAlaska.Net and McGrath Light and Power. “Over time, I anticipate that all of our accounts will shift to wireless. This is financially viable. No subsidy is necessary. And I could clone this system for approximately $35,000.”

      “This is really a pilot project to prove that this could work. With the launch of Telstar 7 and GE 10, there is finally more than one satellite providing good service in that state,” says Adam Sewall, CEO of Spectrum Wireless. “With our product, you eliminate the need for additional routers, switches and hubs at the edge.

      “With a wireless network, you can take satellite distribution and extend it horizontally at very low cost. This actually helps the satellite model by reducing costs well below that of the direct vertical satellite link. We offer such things as full routing, a virtual private network, and a firewall combined on a single platform,” Sewall adds.

      HWS: Definitely In A Growth Phase In Africa And Elsewhere

      In Africa, there seems to be quite a lot of HWS activity under way, according to Drew Darby, director of international sales for Sarasota, FL-based Wave Wireless Networking, a division of SpeedCom Wireless Corp.

      “We are doing it all over Africa. I estimate that 10 percent of the wireless units we ship internationally each month are being used in an HWS environment,” says Darby.

      Darby indicates that a recent project in the Congo for the United Nations is a good example of what is unfolding for countless enterprises, ISP’s and governmental agencies all across the continent.

      “We are connecting all the UN agency buildings at eight sites in Brazzaville using some repeaters. The satellite link was already in place when we got there. We installed a Multitech VoIP platform as part of this 2.4 GHz and 5.7 GHz wireless network,” says Darby, adding that Lagos, Nigeria, is perhaps the place where the largest concentration of HWS networks can be found.

      Darby describes Lagos as, “the most densely populated spread spectrum transmission field in Africa.” There, ISP’s such as are deploying HWS platforms for multiple customers. Creating an integrated metropolitan network is often the objective, even when the customer might be another ISP with its own VSAT. Mod Engineering is the Nigerian partner of Wave Wireless.

      Wave Wireless has been actively deploying HWS networks in the Caribbean, too. Earlier this year, Fujitsu Ltd. contracted Wave Wireless to equip and install a HWS network stretching over 30 islands in the Bahamas. The project is scheduled for completion in 2003, and it will link 45,000 students and teachers when it is done.

      San Diego-based Titan Wireless has two subsidiaries actively pursuing HWS customers in Africa. Its New Jersey-based subsidiary, Sakon, currently has two HWS implementations under way in Africa, while another, Ivoire Telecom, has deployed 13 HWS networks. For example, according to Gene O’Rourke, CEO of Titan Wireless, Ivoire Telecom is using satellite capacity from Intelsat, a Titan Wireless SCPC gateway, Viasat Linkway satellite gear, and AirSpan wireless gear in the Ivory Coast. Other HWS systems are in place in Cameroon and Ghana as well, to name just two other countries.

      “We prefer to use either the licensed 3.5 MHz or 10.5 MHz frequencies. In the Ivory Coast, our first implementation at 64 kbps and 128 kbps was sold out completely,” O’Rourke says. “We are still learning about the market. It takes people a while to understand how they are going to use this, and move to 128 kbps.”

      In Benin, where parent company Titan Corp. operates a standalone GSM system with 60,000 subscribers, a satellite link is used to backhaul traffic from rural GSM sites.

      “This HWS phenomenon is not in its infancy, but definitely in a growth phase,” O’Rourke says. “Thus far, we have remained flexible. We are looking closely at trends and capabilities, and watching exactly what customers are going to do as this unfolds.”

      In India, Titan Wireless is working with Sakon, which has just acquired Gateway Systems on a similar series of HWS implementations.

      Alcatel is apparently making substantial headway in this arena, keeping capital expenditures and operating expenditures as low as possible in the process. It has developed its own line of broadband wireless IP terminals and wireless IP platforms, and it has successfully conducted an HWS trial in Mali.

      “This system is based on an Alcatel end-to-end broadband IP solution which is able to offer simultaneously Internet access and voice over IP services to subscribers equipped with very low cost broadband wireless IP terminals,” says an Alcatel spokesperson. ” This system has encountered a large interest from the end-users that were really able to enjoy broadband Internet access, and, VoIP via satellite and wireless.”

      “Following this successful trial in Mali, and the positive market feedback Alcatel has received for such solutions, Alcatel widely markets today end-to-end broadband IP hybrid solutions for low to medium densities areas that are expected to generate substantial revenues in the coming years,” he adds.

      As more deregulation takes place throughout the Caribbean, Mississauga, Ontario-based Primal Technologies is also seeking to use satellite, wireless and prepaid services technology to meet a variety of needs for emerging telcos and CLEC’s, both there and elsewhere in Latin America. Thus far, the company has completed projects in Guyana and Antigua.

      “The TDM satellite channel serves as the long distance link back to North America. Local voice is handled by either TDMA or GSM technology,” says Vice President Michael Conway. “To assist in the deployment, we monitor and track the Primal Service Nodes remotely. You cannot simply set the customer up and then let him go. It is also easier to get them operational by providing some vendor financing.”

      Conway sees a defined sequence consisting of four distinct phases, which works to the advantage of the vendor and the service provider. After the voice-only wireless network goes up, and billing for voice traffic is under way, revenue is generated and a decision can be made as to whether a VSAT should be deployed or any long distance traffic should be handed back to the local PTT. Finally, the HWS link is shifted from voice-only to include data that enables the service provider to market higher revenue IP services with a VSAT linking directly to a North American gateway.

      “You want the CLEC to have a method to get into the game, while avoiding huge start-up costs. It means dropping the business model from a 7-figure to a 6-figure solution so that it begins to make sense,” Conway says.

      Non Profits And The 2002 Winter Olympics Zero In On HWS

      Non-profit organizations such as the World Resources Institute, and, The Bill and Melinda Gates Foundation are looking hard at HWS as a way to bring IP services to otherwise unserved areas of the world. It is seen as a vehicle for social change that goes beyond creative community building, adding value to what can often be a highly impersonal global economic development agenda in the 21st century.

      “The challenge is to find funding sources for customers,” says Emil Youssefzadeh, chairman and CEO of STM Wireless in Irvine, CA. “The demand is there. It is a question of affordability.”

      STM Wireless was recently awarded a patent for its SpaceLoop, a VSAT with a built-in wireless base station which serves as a turnkey local exchange that interfaces with DECT handset or wall unit. Each SpaceLoop can serve as a switch capable of serving up to 256 subscribers. Another product, known as SpaceWeb, is used for broadband access.

      “We backhaul on the network side, and use the satellite as a switch in the sky to provide links between VSATs. We provide interconnectivy to the gateway as well. It is seen primarily as a way to supplement an existing phone network,” says Youssefzadeh.

      Salt Lake City-based OnSat Network Communications Inc. is using SpaceLoop and SpaceWeb, among other things, as part of its “Solar.Net Villages” initiative which is a huge HWS project getting under way in Panama and Honduras with backing from the World Bank and the OAS/IICA.

      “Over the next few years, we have a contract to [connect] 2000 villages in Honduras, and they will all be a combination of HWS. The emphasis is on what we call solar-powered CSAT technology or extremely reliable C-band VSATs with wireless local loop to multiple villages,” says David Stephens, president of OnSat. “We are forging a community-based multi-user solution, and not a series of single user solutions. By combining CSAT with local loop wireless, the cost of the satellite is shared among many users.”

      In the United States, 110 Navajo Chapter houses are going to be equipped with OnSat’s HWS CSAT platforms using 2.4 GHz and 5.8 GHz for the last mile wireless connectivity. This is all thanks to a grant from The Bill and Melinda Gates Foundation. According to Stephens, the first systems have already been installed in New Mexico and Arizona. Some will have to be solar-powered.

      In Park City, UT, which is the home of the 2002 Winter Olympics, an HWS network will be installed to encompass all the ski resorts, various hotels, businesses and homes. As video moves in and out via satellite, OnSat will use the wireless local loop to collect and distribute all kinds of data, voice and video. This HWS network will remain after the Olympics are over.

      “The locals are making sure that there will not be a bunch of satellite trucks and antennas parked in and around the city during the Olympics”, Stephens said. “So, in addition to the miles of fiber they buried all over, we are bringing in one 3.7 meter C-band antenna, and going local loop wireless everywhere in town and on the ski resort.”

      HWS Not Intended To Displace Standalone VSATS

      Readers who walk away from this article with the idea that this is an endorsement of HWS at the expense of VSAT sales are missing the point entirely.

      As noted above, a huge demand exists for basic voice connectivity. In unserved areas, rural telephony projects based on a mix of self-contained VSAT-based call boxes using prepaid cards can move forward in the same area as an HWS network. In addition, both can provide a pair of dynamic and affordable pathways to broadband service options.

      The key here is affordability, reliability and ease of deployment. As for the two-way broadband VSAT that has emerged from the teams at Starband, Direcway and Tachyon, to name a few-this is a high performance product category intended for a far more affluent market segment where cost is not necessarily an obstacle.

      In addition to the companies mentioned above, others such as Frankfurt, Germany-based Cross Atlantic Networks and Israel-based Shiron Satellite Communications Ltd. are showing considerable enthusiasm for HWS, although Shaul Laufer, co-founder and president of Shiron, believes there is reason for varying degrees of support for or interest in HWS solutions among different VSAT vendors.

      “The demand for broadband access and hybrid solutions is a fairly new trend in the industry,” says Laufer. “Once this demand was realized, it took VSAT manufacturers a few years to develop the technology to meet the new needs. Previously, companies were more focused on providing traditional solutions for applications such as lottery, gas station and rural telephony.”

      “The development of hybrid solutions has also been held back by the fact that most VSAT manufacturers are focused on providing direct access via the satellite solutions using single-user satellite terminals, which has not proved to be cost effective,” he adds. “In the hybrid solution, with a single satellite terminal providing service to multiple wireless consumers, and, with user access handled at the WLL level, there is a considerable saving of space segment spectrum. The deployment of a remote cache server beyond the remote satellite terminal further reduces the space segment costs.”

      CA-based eSat is using Shiron’s InterSKY which is easily configured as an HWS solution. This has a standard RJ45 Ethernet connection between the remote gateway and the WLL base station. Asymmetric inbound and outbound paths make the system ideal for Internet access with FTP download speeds of over 1 Mbps, according to Laufer. A WLL base station is co- located with an InterSKY Remote Gateway and can share outdoor infrastructure.

      And yet, while standalone VSAT’s are both quite easy to deploy and easy explain to customers, some Internet service providers in developing markets are still waiting for satellite and wireless vendors to present a compelling package before they broaden their offering to include HWS.

      “We are doing VSAT uplink, DVB downlink. It is the only dependable solution in our market,” says Mark Davies, CEO of which is actively pursuing opportunities for the provision of Internet connectivity in Africa. “I am not sure that I understand the wireless grid. But yes, performance and a direct connection to international bandwidth were the reasons for going with a VSAT.”

      Finally, despite the appeal of HWS, any sense of harmony is often hard to detect when it comes to relations between the satellite and terrestrial wireless sectors. The efforts by Northpoint Technology Ltd. and MDS America to use the same Ku-band frequencies on the ground as the DBS sector has triggered howls of protest from DirecTV Inc., and Echostar Communications Corp., for example.

      At the same time, the wireless industry is upset by the proposed installation of hundreds of wireless repeaters by companies such as New ICO as part of its planned 2 GHz Mobile Satellite Services (MSS). While the new Satellite Digital Audio Radio Service (SDARS) providers, Sirius Satellite Radio and XM Satellite Radio Inc. are encountering the same resistance as they go about creating a terrestrial gap filler network, the FCC okay’d this move, issuing these two SDARS companies a special temporary authority in September with an eye out for any future reports of interference.

      In late September, the FCC denied a petition for reconsideration filed by the Satellite Industry Association which requested that the agency reconsider a decision not to allocate the 2500-2520 MHz and 2670-2690 MHz bands for MSS. It decided that reallocation of the band for MSS use is unwarranted since sharing between terrestrial and satellite systems would present substantial technical challenges. The agency also said MSS already has access to a significant amount of spectrum to meet its future needs.

      Despite these conflicts, HWS moves on. It may not be the hottest game in town, but for many remote sites as well as densely settled urban centers, HWS may well be the most suitable and affordable solution for a long time to come.

      Peter J. Brown is Via Satellite’s Senior Multimedia Editor.

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