Ka-Band: Military and Commercial Sectors Gear Up
By Peter J. Brown
The use of Ka-band is gaining momentum. Throughout the next year, the broadband over satellite sector in particular will know if the overall business model is on target. At the same time, the busy HDTV market should become even busier as HD delivery via Ka-band ramps up.
Boeing is advertising the future DirecTV 10 and DirecTV 11 satellites as among the largest and most powerful Ka-band satellites ever to be launched. At the same time, Harris Corp. is under contract to Boeing to design, build, and ultimately support the integration of the Ka-band multi-beam antennas for the DirecTV satellites in question. The multi- beam technology and extensive frequency reuse is described by Harris Government Communications Systems Division as being enabled by spotbeam antennas similar to those Harris provided to Boeing for the military Wideband Gapfiller System (WGS) satellites. For this reason, and others, we will look at WGS briefly, while exploring the status of the commercial Ka-band sector.
By late 2006, military bandwidth managers at the U.S. Department of Defense will finally get a chance to light up the first of the 5 planned WGS GEO satellites. These Boeing 702s will augment the X-band communications now provided by the Defense Satellite Communications System (DSCS), and augment the existing one-way Ka-band service provided by the Global Broadcast Service (GBS) with two-way Ka-band services using 125 MHz channels as well.
Milsatcom users are not the only ones eager to tap more bandwidth. Bruce Leichtman, president and principal analyst at Leichtman Research Group, Inc., sees an opportunity for satellite broadband in the U.S. among the approximately 20 million households and millions of small businesses that do not have any access to cable or DSL.
But the Ka-band curve continues up and down of late in terms of who is in the race and who is no longer running. In June, for example, as part of the unwinding of the Rainbow DBS VOOM HDTV venture, Cablevision Systems Corp. pulled the plug on the contract it signed with Lockheed Martin Commercial Space Systems late last year involving 5 Ka-band satellites at a total cost exceeding $700 million. Although it reserved the right to restart the contract until late November, the fact that the Rainbow-1 satellite was sold quickly to Echostar Communications Corp. for $200 million seems to suggest that Cablevision has closed the curtain on this chapter.
Here we list in assigned West Longitude (WL) slots, the Ka-band real estate profile on the Clarke Belt over North America. We mention just a few of the players. The trio of DirecTV Group Inc. dba DirecTV U.S., Hughes Network Systems (HNS) and SpaceWay, still hold Ka-band licenses for 103, 101 and 99. EchoStar already operates a Ka-band satellite, Echostar IX at 121, and has Ka-band authorizations at 97, 113 – once assigned to Visionstar – and 117. Echostar’s Ka-band license at 121 allows use of only 500 MHz of Ka-band spectrum in each direction, while its FCC authorized licenses for 97, 113 and 117 involve 1000 MHz in each direction.
SES Americom Inc. relinquished three Ka-band slots last year, but retains 85 and 105, which are used in part by Echostar. Wildblue Communications has 111.1 and 109.2. Other licensees listed last year included Cablevision and Rainbow DBS with authorizations at 129,119 ,77 ,71 and 62, and Pegasus – a DirecTV transaction not withstanding – which held authorizations for 107 and 87. DirecTV did not acquire these frequencies.
"Ka-band will be mainly used for HDTV. By 2007, DirecTV plans to implement MPEG-4 AVC via Ka-band satellites in three orbital slots so as to offer more than 1,500 local HD channels and more than 150 national HD channels and other advanced programming services," says Benoit Denis, space and communications research analyst at Frost & Sullivan in Paris.
"Europe is not yet using Ka-band for video, although Eutelsat might be pushed to it as they have absolutely no more space on their prime orbital locations. SES Astra, however, still has space for more Ku-band," he adds.
According to Roger Rusch, president of Telastra Inc., Ka-band is best suited to regions of low rainfall. Where there are tropical rainstorms, there will probably be outages when it rains.
"Although there are mitigation techniques, these are probably not adequate to preserve communications in a tropical squall. It also seems apparent that the developed parts of the world have greater needs for communications service and therefore will need to exploit Ka-band sooner. In terms of business models, it is difficult to be certain, but business users are most likely to want broadband services in remote regions," says Rusch.
Overall, the most important technology impacting Ka-band operations is adaptive coding that will maintain communications while throttling back on the data rate, when needed.
"Broadband and video are completely separate businesses. The fundamental issue is two-way communications versus broadcasting (point to multipoint). Satellites are great for broadcasting, but few two-way systems have become major service providers," he adds. "There is very little Ka-band service anywhere, just a few small examples. Caution seems well founded as new services are introduced."
U.S. DBS Players Embrace Ka-Band
Along with its six Ku-band satellites, DirecTV already has Spaceway F1 at 102.8, a Ka-band Boeing 702, and DirecTV 8 at 101, a Space Systems/Loral-built Ku/Ka-band hybrid. Another Ka-band Boeing 702, Spaceway F2 will follow later this year at 99.2. Together, they will provide capacity to roll out local HD channels in 24 markets by year end and another 12 markets in early 2006, according to DirecTV spokesman Robert Mercer. In 2007, DirecTV will launch two more Ka-band satellites, DirecTV 10 and DirecTV 11, to expand its local and national HD services. Thomson, Samsung and LG Electronics will be providing set top boxes for the DirecTV Ka-band system, while Tandberg TV is providing MPEG-4 AVC compression equipment.
"It looks like MPEG-4 AVC is emerging as the preferred standard for DBS. For HD video delivery, 8PSK is the next modulation technique and turbo coding adds further efficiency," says Aditya Kishore, director, media and entertainment strategies at Boston-based Yankee Group.
"DVB-S2 technology is key to enabling us to close the Ka-band links. DirecTV and HNS were key players in the development and implementation of this new technology," says Mercer.
While throughout the past few years, there has been lots of skepticism about what might unfold with respect to Ka-band broadband services, the video dimension is a whole new ball game.
"By shifting its pair of Spaceway Ka-band satellites from broadband to video and taking a $1.4 Billion write down in the process, DirecTV has suddenly opened up what could become a huge new market for Ka-band," says Patrick French, regional director, Europe, and senior analyst at Northern Sky Research. "DirecTV actually caught the industry off guard, despite the leasing of SES Americom Fixed satellite Services (FSS) Ka-band capacity by Echostar."
"Not only has this caused North American commercial satellite operators to wonder if a shortage of Ka-band capacity looms on the horizon, but it also impacts satellite operators in Asia and Europe. In those regions, the marketing of Ka-band broadband services to date has been largely unsuccessful and there is no significant video activity thus far. Now, thanks to DirecTV, these operators are assessing their options to determine if replicating what seems to be unfolding in the North American Ka-band market is really worth their time and money," he adds.
As part of the 50 percent sale of HNS to SkyTerra, HNS owns Spaceway F3, according to Judy Blake, an HNS spokeswoman who reports that plans call for a launch in 2006, with service commencing in 2007.
"It will be used for high-speed, broadband satellite services for all market segments. Mesh connectivity will be available as well as spot beams," says Blake.
Spectrum Is What Counts
With a fleet of eight Ku-band DBS satellites – EchoStar I through EchoStar VIII – Echostar Communications Corp. is now adding Ka-band capacity via hybrid FSS Ka-/Ku-band satellites, starting with EchoStar IX at 121, according to Echostar which declined to answer our Ka-band questions and referred us instead to recently released public financial disclosure documents. Echostar has two additional Lockheed Martin A2100 Ka-band satellites on order, with completion expected during 2008. Both could allow Dish Network to offer other value-added services including two-way broadband and video – the emphasis here is on the declaration of an optional broadband application.
Echostar is leasing one entire polarity of the dual Ka-band payloads on a pair of SES Americom hybrid Ka-/Ku-band satellites, AMC-15 at 105 and AMC-16 at 85. Both of these designated Americom2Home satellites are A2100AXs built by Lockheed Martin Commercial Space Systems and equipped with twelve 125 MHz Ka-band spotbeams powered by 75-watt TWTAs, along with their Ku-band payloads.
In August 2004, the FCC International Bureau authorized SES Americom to launch and operate AMC-15 in the 11.7-12.2 GHz, 14.0-14.5 GHz, 18.6-18.8 GHz, 19.7-20.2 GHz, 28.4-28.6 GHz, and 29.5-30.0 GHz frequency bands.
The FCC wrote, among other things, that "The AMC-15 satellite is authorized to operate its service links in the following Ka-band frequencies: 18.6-18.8 GHz and 19.7-20.2 GHz downlinks (right-hand circular polarization) and 28.4-28.6 GHz and 29.5-30.0 GHz uplinks (left-hand circular polarization). This amounts to an overall reduction of 600 MHz in bandwidth from what the Commission previously authorized for SES Americom’s Ka-band service links."
We include the specific FCC language to underscore how dynamic the process of planning for, assigning and ultimately deploying Ka-band spectrum can be.
WildBlue: The Curtain Goes Up
For Tom Moore and the team at Wildblue Communications, entering the broadband market in North America is a dream come true. But now, Wildblue has to deliver and Moore has a lot more to think about these days than simply whether or not in the end he can offer a bundled services package with either DirecTV or Echostar, or perhaps even terrestrial wireless service providers.
"When we signed up our first customer in June, we had activated and tested all 31 spot-beams and had service available in 48 U.S. states. Manufacture of subscriber equipment is going well and the supply chain from the various manufacturers all the way to the installers is now fully established and working well. More than 1,000 installers have been trained," says Erwin Hudson, executive vice president and chief technology officer at Wildblue.
Wildblue has finally launched its Ka-band DOCSIS-based, rich-media-capable service offering in the United States on Anik F2, a Boeing 702 at 111.1. Plans call for a possible second Ka-band satellite, Wildblue-1, which could occupy the 109.2 WL slot, but there is no timetable for this satellite yet.
Anik F2, a Boeing 702 at 111, weighing 5910 kg, carries 45 Ka-band circular spot-beams with 30 licensed to Wildblue and 15 dedicated to Telesat’s Canadian customers. The power levels on Anik F2 are 55-58 dBW at saturation and total throughput ranges between 3 and 4 Gbs.
Anik F2 uses a half dozen wideband 492-MHz transponders to beam traffic to six gateways – three each in the United States and Canada – relaying multiple MF-TDMA return carriers from users grouped into six to eight beams in the process. The F2 gateways also use a series of 56-MHz transponders powered by 31X90-watt TWTAs to access users in each spotbeam. Because spotbeam coverage must always address the ever present possibility of rain fade, which requires variable uplink power at both the terminal and the hub, 17 spotbeams are designated as heavy rain beams for customers in the eastern half of North America with a single 90-watt TWTA assigned to each beam. The other 14 TWTAs support a pair of beams each.
According to Hudson, the network management system for Wildblue is based on commercially available products and enhanced with Wildblue-unique features.
"Our network management engineers monitor key performance parameters – signal strength, signal quality and error status, for example, both in real time and historical – of each subscriber terminal, both in aggregate and on a subscriber-by-subscriber basis. Each terminal is an SNMP-enabled node in our network," says Hudson. "We do a network-level quality check of each new install and we continue to monitor performance throughout time. The Wildblue system is designed for automatic acquisition and automatic provisioning of new terminals and our installs are comparable in complexity to the satellite television ones that our installers have done in the past." Wildblue subscriber terminals are also designed for over-the-air software upgrades, allowing for continuous improvements to network performance and easy feature enhancements. Wildblue has five unmanned gateways scattered across the United States, operated entirely by remote control from Wildblue’s Network Operations Center in Denver. "Our gateways include a number of commercially available Internet appliances which have been adapted by Wildblue to effectively perform latency mitigation, load balancing, caching, HTTP acceleration, DNS and proxy functions in a satellite environment," says Hudson.
Next generation satellites with higher power and larger payloads are being scrutinized by Wildblue.
"We also have a technology road map that will enable significant cost reductions on the subscriber terminals with time and volume. Emerging microwave integrated circuit technologies such as GaN may be 10 times less expensive than the GaAs power devices we currently use in the transmit electronics on our outdoor unit," says Hudson. "Use of next generation cable modem chip sets, which are evolving rapidly for non-satellite applications, may allow us to reduced the cost of our indoor unit by two to four times."
"We intend to maintain the competitive advantages we have today in both performance and cost, and although we do not target customers with access to DSL and cable modem service, we believe we can continue to provide our customers with satellite broadband services that are comparable to wired offerings in both price and performance as price points and performance expectations change throughout time," he adds.
Telesat Canada’s Ka-band services in Canada are available from Barrett Xplore Inc., the national ISP, and the NetKaster division of Northwestel Cable Inc., which serves as the ISP for Northern Canada.
"All of the Ka-band capacity is now in use and we are offering a national service. There are subscriber terminals operating in every beam in Canada on Anik F2 today. High volumes of terminals are now being delivered from the manufacturers and the rollout of service is ramping up," says David Lahey, vice president of business development at Telesat, a wholly owned subsidiary of BCE Inc. "Telesat’s Ka-band services are being offered to the consumer market only at this time."
"We expect that VoIP will drive demand of the Ka-band service considerably. The Ka-band platform is being enhanced to allow us to effectively provide this service and Telesat’s service providers are in the process of developing a VoIP service they could offer their customers," he adds.
Ka-Band: Challenging Network Management
The Ka-band satellite broadband to the home market requires a state of the art network management system (NMS) to efficiently and effectively manage network operation centers (NOCs), hubs or gateways, and remote sites. The teleport NMS model does not fit well here.
"Each application represents unique challenges. The NOC system must act as a manager of managers (MOM). The hub system must perform the functions of a classic monitoring and control (M&C) system, a MOM and a Simple Network Management Protocol (SNMP) manager," says Dan Ostrouch, director of business development at NH-based Newpoint Technologies, Inc.
"Some minimal management of the customer terminal must also be available. To keep costs low, the user terminal employs integrated management capabilities using the same carrier that is transporting internet traffic," he adds. "If a circuit fails, the terminal NMS can not talk to the remote site to determine corrective action and the NOC has no method of determining local conditions including power levels, and the presence of rain, for example."
To solve this problem, Newpoint Technologies provides low cost remote site managers to monitor the condition of terminals. Should a communications failure occur in this unit, the Newpoint Mercury communicates conditions back to the NOC via PSTN or Iridium satellite connection, while Newpoint Mercury Remote Site Manager provides additional capability including graceful start up, and shutdown, notifying a user community of satellite communication difficulties and automatic restoration of communications. The Newpoint Compass system has been developed as both an M&C solution and a MOM, with the ability to develop SNMP interfaces on the fly.
Newpoint Technologies joined with four other companies including SAT Corp. to form the SAT Alliance, which offers satellite operators and service providers plug and play software applications. Frequency planners depend upon sophisticated model – "the plan" – as they try to maximize use of the spectrum and power without causing unwanted interference due to intermodulation, for example. Balancing link budgets based on the uplink capability of the satellite users and any expected rain fade is a delicate process, according to Bob Potter, president of SAT Corp.
"When the plan is automatically passed to the traffic monitoring and interference detection system, we know what is supposed to be on the satellite and the traffic link budget parameters. We can automatically determine if the plan is being met and detect if there is any interference," says Potter. "If interference is detected, the parameters of the interference can be used to search a database to find the user causing the interference or pass the parameters to a geolocation location system, which finds the location of the transmitter."
Having the means and technical know how to create and refine the plan is just one small part of an overall Ka-band NMS solution. Pilot generation – generating a test signal on the ground and transmitting it to the satellite for power level and frequency stability control purposes – is another important concern.
The leap into Ka-band expands the available bandwidth enormously via DVB/ATM-based carriers designed for MF TDMA traffic, for example. Whereas the individual transponders for normal Ku-band are 27, 36, 54 or 72 MHz, Ka-band transponders ranging as high as 500 MHz are not unusual, although the trend appears to involve 100, 125 and 200 MHz increments.
"Typically right now, each signal is only 72 MHz wide (making six or seven signals per transponder), but the system can be expanded once the ground hardware is available," says Potter.
SAT Corp. provides Ka-band spotbeam monitoring, pilot generation and TDMA peak power measurements to companies like SES Americom, SES Astra and iPstar, among others.
"Besides interfacing with the NMS for alarm detection and alerting, end point monitoring devices need to be smarter, smaller and cheaper than any other conventional system, because the beams are smaller and there are many more of them," says Potter. "The system needs to be driven by distributed intelligence, so that any site is independent when the network goes down, but is then a slave to the master once the network is reconnected."
The Anik F2 NMS was provided to Telesat Canada by ViaSat as part of the overall system delivery. Products from Cisco, Mentat, Solar Winds and others, that were developed for the broadband cable market, were modified to allow them to manage the Ka-band DOCSIS platform, according to Lahey from Telesat.
"These systems provide the same level of management as can be delivered on a cable network, allowing visibility, control and quality of service down to the application layer on any particular remote terminal device," says Tom Eidenschink, director, consumer broadband at ViaSat, Inc. "In the NMS area for our Surfbeam system, this means tapping into the Operational Support Systems and Business Support Systems (OSS/BSS) that have been successfully developed and deployed for terrestrial broadband networks. These OSS/BSS solutions have been field proven to support large networks, on the scale of millions of subscribers, as well has having the proper functionality to cost effectively support these larger networks."
"Other modified VSAT systems have been challenged to demonstrate that they truly can scale and be a cost effective solution for the service provider at the same time," he adds.
The fact that the newer generation of Ka-band satellites have been designed to support a larger subscriber base than their predecessors makes scalability even more important.
"This is a combination of better engineering the payload to the application, as well as delivering a more powerful payload that can support the more efficient satellite waveforms available today. 8PSK turbo-coded technology can easily be deployed on these newer Ka-band satellites, offering more bits per Hertz than could be done before," says Eidenschink .
He agrees that it is most likely that Ka-band hub/spoke system versus mesh ground systems will end up relying on different NMS than their Ku-band counterparts.
"The Ka-band hub/spoke system lends itself to integration with existing NMS solutions developed for the terrestrial market. The mesh systems tend to be more custom, making it very difficult to leverage existing NMS solutions developed in terrestrial/wireless markets," says Eidenschink. "So, I see the mesh NMS market remaining proprietary or custom in nature, while the Ka-band hub/spoke continues to push towards open standards-based solutions."
The U.S. Military Awaits More Ka-band Capacity
Today, the U.S. military relies on the Ka-band Global Broadcast Service from three of the Boeing-built fleet of eight operational UHF Follow-On satellites, F8 through F10. Each is equipped with 4X130-watt, 24 Mbps Ka-band transponders and three steerable downlink spotbeam antennas as well as one steerable and one fixed uplink antenna.
When the first of five WGS satellite activates late next year, WGS controllers will be required to dynamically and simultaneously focus required satellite coverage and capacity when and wherever needed by deployed forces. The decision to include Ka-band along with X-band on WGS opens the door to the many perceived advantages of Ka-band including greater bandwidth, increased data throughput and smaller receive antennas.
WGS involves conventional transponded (bent-pipe) satellites with all NMS on the ground. ViaSat is supplying the Enhanced Bandwidth Efficient Modem, while Titan Corp., which was recently acquired by L-3 Communications, is providing the U.S. Army with Ka-band Satcom Augmentation Terminals.
According to Mark Hayes, vice president and director of communications systems at ITT Industries, systems division, WGS network controllers located at the Wideband Satellite Operations Centers (WSOCs) must have immediate access to the status, performance and usage of all satellite, terminal and link resources. Using the Integrated Network Monitoring and Control Subsystem (IMPCS), controllers can exert positive control over all terminals accessing the WGS by interacting directly with the terminals through automated control circuits and secure voice order wires provided by the IMPCS.
"As the complexity of the satellites increases, so must the monitoring and control systems employed to manage these critical communications assets. The IMPCS is designed to provide integrated spectrum monitoring, signal characterization and link power control capable of sustaining communications through severe rain fades given one-way rain fade of 30 dB per minute at Ka-band frequencies," says Hayes.
When combined, X- and Ka-bands on each WGS satellite represent about 1500 MHz of bandwidth. However, the actual bandwidth supported by the WGS payload is much greater as portions of each frequency band will be reused in different coverage areas illuminating different portions of the earth.
"Circular polarization and spatial reuse of frequency results in a total of about 1800 MHz of X-band bandwidth and more than 2700 MHz of Ka-band bandwidth per satellite. This combination of antennas coupled with the WGS’s ability to digitally route spectrum in 2.6 MHz sub-channels provides virtually unlimited flexibility," Hayes says.
The Spectrum Monitoring Subsystem, an integral component of IMPCS, enables controllers to continuously monitor the entire WGS spectrum or controller-selected portions of the satellite’s X- and Ka-band coverage areas. It alerts the WSOC controllers to interference, unauthorized users and out-of-tolerance conditions.
"Since the WSOC will not be illuminated by all of the WGS spacecraft’s separate downlink coverage areas, the WGS provides a spectrum tapping capability to sequentially sample the spectrum in 10-20 MHz bandwidth increments and downlink these samples to IMPCS," says Hayes. "IMPCS features a WGS synchronization receiver to reassemble the downlink at the WSOC for effective monitoring of the entire X- and Ka-band spectrum. IMPCS also provides C- and Ku-band interfaces to provide advanced monitor and control of all satellites operating in any of the four satellite communications bands."
No Turning Back
As for Ka-band developments in Europe and Asia, there is some confusion about what is really happening. Look at iPstar, for example. Anik F2, weighing in at 5200 kg, was the largest commercial satellite in the sky until the successful recent launch by Thailand-based Shin Satellite Plc. of iPstar-1 (Thaicom 4) – topping the scales at 6775 kg – with its Ka-/Ku-band payload at 120 degrees East.
An industry press release declared, among other things, that, "Thaicom 4 (iPstar) will use its seven on-board antennas to create 112 spot and regional beams in the Ku and Ka frequency bands."
We turned to Shin Satellite spokesman Richard Jones in Bangkok for help.
"It looks like there is a problem from the start as iPstar does not use Ka-band for connections to customers. We have minimal capacity for the uplink from the control centre to the satellite only. All our spot beams are Ku-band. I don’t know how this misunderstanding came about, but iPstar is essentially a Ku-band satellite," says Jones.
As for New Skies Satellite NV’s NSS 6, this uses Ka-band uplinks only, too. With Digital Multimedia Broadcasting via satellite now making headway in Japan and South Korea, thanks to MBsat, and with satellites with partial Ka-band payloads in the region including Koreasat-3, and, the SCC Superbird and Jsat Nstar satellites serving broadband markets in Japan, there is much to discuss. But it must wait.
Here in the United States, things like the Universal Service for the 21st Century Act (or S. 1583) and the recent decision by the Texas legislature to grant telcos a one-stop, statewide franchise will alter the Ka-band landscape again. On Capitol Hill, powerful senators with increasingly vocal and unserved rural constituents are saying enough is enough. Tired of waiting for an affordable broadband solution to penetrate the rural heartland, they introduced S. 1583 to amend the Telecommunications Act of 1996 and create a subsidized base of support for rural broadband service provider with an annual outlay that could amount to as much as $500 million.
Ka-band is maturing and now redefined as a video solution rather than a broadband vehicle only. This proves that the process of finding new revenue streams for Ka-band is just getting underway and the potential out there is enormous.
Peter Brown is Via Satellite’s Senior Multimedia & Homeland Security Editor.