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WiMAX World 2008 was held once again at Chicago’s McCormick Place Conference Center from September 29 through October 1st. The event brought together businesses engaged in 4G network development, including component and equipment manufacturers, service providers, content and application developers, and the financial investment community. The underlying goal of the conference was to bring together these diverse yet inter-related entities to engage each other with regard to the opportunities and barriers for WiMAX technologies. Since 2004, WiMAX World has grown from 700 attendees and 14 sponsors to over 8,000 attendees and more than 250 sponsors in 2008, slightly down from the previous year. Still, with those attendance numbers, the Conference and Expo claims to be the world's largest event showcasing next-generation mobile broadband and WiMAX technology solutions.
This year the organizers expanded the conference program by incorporating a 4G Executive Summit hosted by the Yankee Group. Despite a tumultuous year in finance and the slower than expected roll-out of WiMAX, the organizers were quick to point out that this year’s event coincided with the massive Sprint/Clearwire WiMAX deployment in the US, the largest WiMAX network deployment to date.
“WiMAX is intended to provide personal broadband to consumers and enterprises over a mobilized Internet. ”, according to the conference chairman, Eliot Weinman, “The challenge will be to extract further ROI from existing networks and services by reducing the CAPEX necessary to scale and grow them”. Much of the excitement comes from the promise of WiMAX to extend the Internet (in an economically feasible way) into markets and geographies were no current infrastructure exists.
During this opening event, the organizers of this new executive summit acknowledged the disruption of existing business models and the race to 4G that exists between WiMAX and LTE. This looming battle became clear during the various talks. The Summit was a full day affair, hosted by Berge Ayvazian, the Chief strategy Officer with the Yankee Group and included a keynote speech by Hank Kafka, the VP of Architecture for AT&T on “Operator Strategies for 4G Networks” as well as a talk by Charlie Martin, Wireless Chief Technology Officier for Huawei Technologies (USA) followed by a 4G executive roundtable, networking lunch and four afternoon sessions on infrastructure strategies, 4G Device and CPE strategies, regulatory and spectrum policy; and 4G applications workshop. In all, the program was designed to deliver comprehensive thought leadership on several key topics including:
• Personal and Mobile Broadband Services
• Enabling Disruptive 4G Mobile Technologies
• Wireless Broadband and Mobile Applications Strategies
• Mobile Content and Commerce Strategies
• Mobile TV, Quad Play, and Broadband Embedded Consumer Electronics
• New Business Models for Personal Broadband and the Mobile Internet
The 4G Executive Summit Talks
According to AT&T's Vice President of Architecture Hank Kafka during his keynote, “For the U.S. wireless market to meet the soaring demands of consumers, we have got to set targets, but targets without a plan are only wishful thinking. In general, most of our operators have similar 4G targets but the difference will be in the path to those targets."
The nature of that path was the main topic of discussion. AT&T’s Kafka extolled the virtues of GSM and its long-term evolution (LTE)."Our evolution has been from GPRS to EDGE to UMTS to HSPA and soon LTE," Kafka said. "It's clear that LTE will fit neatly... This is the great advantage of the GSM evolution: We are not starting from scratch. GSM can build from the existing technologies. It takes years for new technologies to get broad coverage nationwide."
While AT&T envisioned an evolutionary path toward 4G, the summit's chair and moderator, Yankee Group's Chief Strategy Officer Berge Ayvazian, considered a more dramatic “revolutionary” It's also clear that AT&T does not see 4G as a revolutionary step, at least in terms of networking. The summit's chair and moderator, Yankee Group's Chief Strategy Officer Berge Ayvazian, however had a different take. "I went to bed last night with nightmares," Ayvazian deadpanned. "I couldn't start this session without noting that the 4G revolution is coming amidst a meltdown--a global financial crisis... The failure of Congress to pass the bailout led to unprecedented 777 points and $1.2T loss... Why am I even talking about this? Bank failures, nationalizing major companies... What does this mean? What a day to launch the 4G revolution, right? It's a perfect day. In the midst of a crisis you launch a revolution."
For the next few years at least, 3G networks will be under constant improvement and so one might ask (as Pat touches upon in his blog entry of September 30th), where can the 4G label be used and when is it relevant? If HSPA+ will be WiMAX's biggest competitor while LTE is in the works, where does 3G stop and 4G begin?
One possible answer to this question was suggested during the summit by Huawei USA's Wireless CTO Charlie Martin. During his keynote this morning, Mr. Martin stated, "The ITU will specify which technology is and isn't 4G, but there is no doubt that 3G is converging toward LTE. When it comes to 4G the emphasis has been on bandwidth... in our WiMAX launches we have not seen mobility as a factor. Most of our WiMAX launches are for bundled services that include VoIP and basic broadband offerings. So, for Huawei it's generally very clear to us. We don't get in many super-competitive situations [LTE vs. WiMAX deployments]. It's almost always very clear cut."
The microwave component industry was well represented by wireless backhaul equipment manufacturers, test & measurement vendors, integrated device manufacturers, cable and antenna manufacturers. Among the list of exhibitors were names such as Aeroflex, Agilent, Anritsu, Berkeley Varitronics, Huber + Suhner, M/A-Com, Nitronex, SiGe Semiconductor, Triquint and Wavesat.
Agilent Technologies showcased their fixed and mobile WiMAX test solutions at the show, offering a full complement of products for R&D, design verification, manufacturing, protocol conformance and interoperability test, as well as network deployment and maintenance/service quality.
Among the products and applications being demonstrated was the new Agilent (N5106A) PXB MIMO Receiver Tester. We (MWJ editors) had the pleasure of a personal demo of this systems in our offices, two weeks before the show. The news release was made public during the show, so attendees were among the first in the world to see this test solution. The test solution is a combination of new software and hardware, that offers a reconfigurable architecture and internal signal routing to deliver signal-creation and channel-emulation capabilities for WiMAX and LTE standards. It supports 2x2, 2x4 and 4x2 MIMO with bandwidth of 120 MHz, and features custom MIMO correlation settings (e.g., channel models, antenna pattern and correlation matrix) controlled through an easy-to-use interface that will save hours on equipment and lab set-up time. The system allows the re-use of existing equipment, such as signal generators/analyzers (Agilent MXA and MXG/ESG) and allows input from signal creation tools such as Matlab, Signal Studio and ADS.
Also being shown was the Agilent E6651A Mobile WiMAX test set, featuring end-to-end data throughput rates of more than 10Mbps (UDP). The E6651A is also at the heart of Agilent's Protocol Development and Conformance Test solutions, with 3.5GHz test case validation under way.
Berkeley Varitronics Systems deserves special recognition for their very creative exhibition stand which, playing off the name of their YellowFin WiMAX analyzer, had a fishing theme throughout. Company representatives were decked out in fishing vest and collapsible chairs were set up for their scheduled in-booth product demonstrations. Along with the various field Wi-Fi & WiMAX spectrum/packet analyzers on display throughout the stand, it was also hard to miss the only mermaid in attendance, handing out product information and wooing visitors.
MIMO testing was very much on the minds of the folks at Keithley, as they were showing off the System 2800-MIMO RF Signal Analyzer and System 2900-MIMO RF Signal Generator both now supporting up to 8x8 configurations. The new 8x8 configuration, I was told is an industry first! The test system is ideal for antenna research, 802.11n WLAN, 802.16e mobile WiMAX Wave 2, and LTE. Performance includes 40MHz bandwidth, high performance platforms, 2820 SISO EVM -40 dB (40 MHz BW, 5.8 GHz – characteristic); +/- 1 ns signal sampler synchronization and waveform ARB alignment and <1 degree peak-to-peak RF-carrier phase jitter. Each system can be initially configured as a 2x2 system and then upgraded to three, four, or up to eight channels. In this configuration, the system can analyze up to eight OFDM channels with up to 16 signals. The signal analysis software automatically detects the 802.11n modulation coding scheme and its measurement set includes SISO measurements such as Error Vector Magnitude (EVM), frequency error and MIMO measurements such as Channel Response and Cross Power.
Just prior to the show, Rohde & Schwarz and Beceem Communications Inc. announced their collaboration to provide a custom test solution for Beceem’s mobile WiMAX chipsets. Based on the award-winning R&S CMW270 WiMAX communication tester, this turnkey solution will enable Beceem’s customers to develop and test mobile WiMAX products reliably and efficiently. A live demonstration of the CMW270 WiMAX communication tester in combination with Beceem mobile WiMAX chip reference designs was presented at the show.
The custom test software developed by Rohde & Schwarz provides RF alignment and verification for a wide range of products based on Beceem WiMAX chipsets. The software has been approved by Beceem as meeting the company’s stringent calibration standards. Multi-evaluation measurements and parallel TX/RX test algorithms were implemented in order to significantly reduce chipset configuration and handling times. Internal switching between RF channels was also employed to improve RF calibration of multi antenna devices (MIMO) by eliminating external adaptation.
The company representatives at Rohde & Schwarz also wanted us to take a look at their new SMBV100a vector Signal Generator, which claims to have the highest modulation bandwidth and output power (up to 6 GHz) in its class, multi-standard support and internal baseband signal generation supporting a number of digital standards (e.g. WiMAX, HSPA+, LTE). Touting a “future-proof” hardware concept, the SMBV100A represents a carefully planned instrument concept. Through different configurations, the instrument can function as a pure I/Q upconverter, cost-effective signal generator with integrated ARB or an advanced vector signal generator with internal signal generation and real-time capabilities.
As wireless systems evolve toward higher date rates, air interfaces will require wider bandwidths and better spectral efficiency. In turn, technologies such as MIMO and beamforming will lead to the need for more accurate laboratory testing of devices, applications and networks emulating real air interface conditions using standardized radio channel models for validating basic functionality. To address this need, Elektrobit of Finland was demoing their new Propsim F8, the markets only channel emulator that is designed to support any existing 3GPP/3GPP2 WCDMA, GSM, TD_SCDMA,EV-DO/CDMA2000, TETRA, IS-54,802.11n 3GPP LTE, WiMAX and Wi-Fi radio interfaces and future wireless system air interfaces. The unit has up to 8 fading channels with up to 32 logical fading channels in a single unit, multiple units can be synchronized to work as one unit, 125 MHz bandwidth with up to bi-directional 4X4, uni-direct 4X8, 2X16 MIMO and 70 MHz bandwidth with up to multiple 2X2, 4X4, 8X8, 2X16, 4X16 MIMO.
WiMAX and 4G infrastructure clearly relies on microwave equipement such as cables, antennas, filters lightening protection and other hardware components. A number of microwave hardware manufacturers were on hand including Amphenol Antel, Inc. (high performance base station antennas); Anatech Microwave Company (Ceramic & cavity filters, duplexers/diplexers, power-dividers, dicrectional couplers, circulators, isolators, antennas and more); Conner-Winfield (timing and synchronization products, precision GPS timing solutions for WiMAX); ET Industries (Adaptive antennas); Huber + Suhner (cables, connectors, antennas); Jaybeam Wireless (Antennas); Jauch Quartz America (crystals and oscillators); Laird Technologies (antennas and power products for handsets, two-way radios, in-building wireless networks, telematics); NDK (Crystals, XOs, TCXOs, VCXOs, OCXOs, crystal and SAW filters); and Phazar Antenna Corp. (custom and omni-directional antennas).
Nitronex was showcasing new performance data on their 28V, 5 watt HEMT devices, the NPTB00004. The new performance data in the 5.1-5.2GHz and 5.7-5.8GHz ranges will help designers working with 5.2GHz WiMAX and 5.8GHz WiMAX systems with specific details about the device performance at these frequencies, including linearity (%2 EVM at 5.2 GHz and 400mW average output power or 630 mW at 5.7GHz. Design information such as s-parameters and load-pull characterization is also available. Talking with Nitronex engineer Walter Nagy, we were able to learn that many PA designers are looking into GaN in part due to its broadband performance in power amplifiers (the result of higher output impedance) and ruggedness. Still, much of the industry needs a primer on depletion-mode devices (requires a negative gate bias). For more information, go to this month’s (September 2008) Expert Advice “GaN Essentials”.
M/A-Com did not have any products released specifically for this show, but they were exhibiting WiMAX products from their portfolio including the MASW-007921, DC-7 GHz SPDT RoHS compliant switch for applications that require low insertion loss and fast settling times over a wide frequency range in an ultra small package size. In many linear systems such as WiMAX, LTE, and Ultra Wide Band, linear benchmarks are critical for superior system performance. The MASW-007921 has an especially high initial compression point (40dBm @ 3V), well-suited for complex modulations such as OFDM, with large peak to average power level.
Ultra fast settling speed in both the receive and transmit path is a critical specification among many linear system and the switching time that is required from the software/baseband to the output power at the antenna can vary widely from application to application. The M/A-Com product development group recognized this attribute and the MASW-007921 settles to more then 99% of its final value within 10uS, whereas similar GaAs switches that do not take this into account typically need closer to 100uS to 200uS to completely settle.
Just prior to the show Fujitsu announced its WiMAX Mobile Wave-2 MAC/PHY chip, an SoC that includes a baseband processor supporting the necessary MAC and PHY functionality, plus the data converters and driver/receiver pins to attach an external RF module. The chip is intended for 2-by-2 MIMO operation, but without beam-forming functionality. It has an added feature of a GPS receiver to implement both network organization functions and whatever location-based functionality that may be imposed by network regulators.
Two special features of the device are its scalability and GPS block. The scalability is provided so that users may implement any size base station from microcells to picocells to femtocells with the chip. Driving this design is the underlying issue that at the WiMAX selected frequencies (2-3 GHz range) --almost every medium besdies free space is highly absorptive. Therefore the familiar scheme of cellular base station antennas scattered around the neighborhood on big towers is of marginal value. In this case, Mobile WiMAX will only deliver interesting bandwidth on line-of-sight connections over short distances (hundreds of meters). Clearly the sort of regular geometric cell structure used by today's cell phones will be inadequate. So the network architects have proposed a hierarchy of base stations. So here’s the thinking behind the GPS block.
This hierarchy starts with a cellular-like topology, complete with the big towers that is augmented by microcell basestations that address any identified shadow areas. These are intended to support a moderate number of clients in a rather limited area. Unfortunately, building materials absorb considerable energy at 2GHz and so even more-localized base stations known as picocells are placed inside structures in order for subscribers to have indoor coverage. Finally, service providers are considering femtocells to address home use (picocells being too powerful and expensive for this purpose).
It is highly likely that these cell sites will interfere with each other depending on weather and the locations of large moving objects such as vehicles. To mitigate this interference, the service provider will have to install the first three levels of base stations—cell through picocell and femtocells will be installed by users (similar to 802.11 hubs today.) Because transmission conditions vary so much, and because the femtocells are basically portable, the network will have to be dynamically self-organization.
Thus the need for GPS. The self-organizing network may need to know the precise location of all of its cell sites, including the femto ones. And each base station must be agile in terms of power, frequency bands, and modulation scheme. So an individual femtostation may be required to handle a compute-intensive baseband load.
This is the emerging challenge for the chip architects. Fujitsu believes it has put all of the base hardware capabilities and software scalability into the PHY/MAC chip to make such a network implementable. And it was certainly getting noticed at the show.
Last March, TriQuint Semiconductor announced a definitive agreement to acquire WJ Communications, Inc., a leading supplier of radio frequency (RF) solutions for wireless infrastructure. The move was intended to expand TriQuint's reach into this market and WiMAX World was one exhibition the company wanted to showcase their new expanded portfolio. The company did not have any new specific products released for this show, however they were present and talking about several relevant products including two relatively new amplifiers for broadband wireless access (BWA), 802.16 (WiMAX) and general S-Band high power amplifier applications.
The two new amplifiers provide a variety of performance advantages, including instantaneous bandwidth of 200 MHz across any segment of the 3.3 to 3.9 GHz band with simple PCB layout and two external components. While designed to support the stringent linearity requirements of multi-carrier applications, both devices are also capable of delivering high saturated power and PAE and the SMT-style package incorporates internal partial matching to simplify PCB design and a high thermal conductivity copper alloy base to maximize heat removal from the amplifier.
The TGA2923-SG is a 10W power amplifier optimized for 3.5GHz Broadband Wireless Access (BWA) and WiMAX (802.16-2004) applications. The TGA2923 can be matched for approximately 200MHz instantaneous bandwidth in the 3.3 - 3.9GHz frequency band with only two additional external components. The TGA2923 is suitable for both BWA base station (BTS) and subscriber station (SS) applications as well as high power, high PAE S-Band applications. In a typical 3.4 - 3.6GHz BWA application, the TGA2923 delivers 9dB power gain, 10W Pout, and an IMD3 level of -50dBc at 28dBm SCL. Typical linear power of greater than 30dBm @ 2.5 percent EVM can be achieved when tested with a multi-carrier OFDM type input waveform.
picoChip announced that Redline Communications, a leading provider of standards-based WiMAX access and broadband wireless infrastructure products, has selected their PC8532 modem to power its next generation RedMAX 4C™ Mobile WiMAX basestations. picoChip is a leading supplier of high-performance multi-core DSP, offering a powerful platform to develop products for emerging global wireless communications markets such as WiMAX, WCDMA, LTE, TD-SCDMA and 4G. picoChip’s products scale from femtocell access points and picocells to sophisticated multi-sector carrier macrocells.
The agreement gives Redline access to a software defined radio (SDR) platform with best-in-class performance/cost ratio. Redline has added its low-complexity maximum-likelihood receiver to the picoChip design in order to increase uplink system performance for coverage and capacity. The software-defined system supports upgrades to future standards, such as LTE, 802.16e Release 1.5 and 802.16m.
Redline, which is also an exhibitor here at the show, sells to carrier and enterprise level organizations in both developed and key high-growth markets around the world, and has more than 166 deployments of its WiMAX Forum Certified™ systems to date. The company has previously delivered mobile broadband to UK and Silicon Valley train networks and created North America’s largest education sector wireless network.
Speaking about the agreement, picoChip’s CEO and president, Guillaume d’Eyssautier, stated: “Our ability to offer advanced IO-MIMO capability and future support for 16m and LTE helped, but the fact that they (Redline) were persuaded by the quality our PHY is testament to the strength of the picoChip offering. We are very excited to have Redline as a key customer.” The Redline RedMAX 4C Mobile WiMAX platform, which is based on the WiMAX industry’s 802.16e-2005 standards for mobile WiMAX, supports a wide range of fixed, portable and mobile wireless services including support voice and video over IP, broadband Internet access used to support high value education, medical, transportation and municipal applications, VPNs (virtual private networks) and other advanced communications services.
The RedMAX 4C is designed to enable operators to maximize the reach and customer density required for a profitable carrier business model. It includes a modular, standardized µTCA (micro Telecommunications Computing Architecture) chassis basestation that is small, lightweight and easy to deploy. RedMAX 4C will also include a suite of indoor and outdoor fixed and portable end-user devices including laptops, mobile handsets and PDAs. Redline’s new WiMAX offering is also designed to facilitate the integration of its existing RedMAX products with its RedMAX 4C technologies, providing operators a path to true mobility.
Ceragon Networks took home the Best of WiMAX World Award for Industry Innovation for its FibeAir IP-10 platform last night at the WiMAX World USA annual awards ceremony. This award recognizes Ceragon’s position as a leader in the wireless backhaul market and the importance of its wireless Ethernet backhaul solutions to the development and promotion of WiMAX. The FibeAir IP-10 combines advanced TDM and Ethernet networking to facilitate the cost-effective, risk-free migration to IP. It can be integrated in any TDM, hybrid or pure/IP Ethernet network and features a powerful, integrated Ethernet switch for advanced networking solutions as well as advanced Service Management and Operation Administration & Maintenance (OA&M) tools.
Exalt Communications, a provider of next-generation wireless backhaul introduced the EX-r GigE series of high-capacity Gigabit Ethernet microwave radios, covering all three 5 GHz bands in a single carrier-class system. The EX-r GigE series gives wireless operators, enterprises and broadcasters a secure, reliable microwave platform with sufficient bandwidth for campus connectivity, camera backhaul, 3G or 4G backhaul, WiMAX backhaul, and high-definition video broadcast.
The series addresses what Amir Zoufounoun, president and CEO of Exalt Communications claims is “a severe bandwidth crunch in their transport networks that cannot be economically solved with leased lines or fiber". The EX-5r GigE and EX-5r-c GigE tri-band 5 GHz all-outdoor radios are designed to address a variety of capacity-intensive applications that previously could be served only with short-range radios such as 60 GHz and E-band radios, or optical fiber. The GigE series delivers 440 Mbps aggregate throughput at link ranges of up to 15 miles with guaranteed five 9s (99.999 percent) availability. By contrast, weather sensitive radios operating in the 60 to 80 GHz bands are typically limited to a range of one to three miles.
Hypres - On Wednesday we met with Richard Hitt, President & CEO of Hypres along with Dr. Steve Gray, Sr. VP and General Manager of their Commercial Division. While Hypres was not an exhibitor, Hitt and Gray were at the show to meet the press and other technologists while attending several talks. Their New York-based company is known for working with superconducting microelectronics and has had some impressive government contracts and development projects of late. They have applied their superconducting technology toward Digital-RF (TM) receiver systems which recently (press release - 08/19/09) resulted in two systems being delivered to Office of Naval Research (ONR).
The Digital-RF (TM) receiver systems delivered to the ONR features a pre-characterized low-pass single-chip digital-RF receiver, a cryocooler with two temperature stages and appropriate cryopackaging, temperature controller, interface amplifiers, dc bias current source, FPGA-based data acquisition hardware, data acquisition software and graphical user interface, and operating manual. Of note, these systems include an additional temperature-controlled stage to permit integration of a high-temperature superconductor analog filter with Hypres’ low-temperature digital superconducting electronics.
The company is now aggressively commercializing this unique technology by targeting a multi-channel WiMAX base station with all digital signal processing up to the final power amplifier as a first project. Definitely looking ahead into the future, both make the case that the RF and economics of 4G are fundamentally different than previous generations and that multi-carrier OFDM is the tipping point where, due to macro-cell complexity, scaling the current hardware approach is prohibitively expensive.
Their solution calls for direct conversion between the RF and baseband signals by way of their cryogenically cooled digital radio housed in the base station performing the tasks of many conventional protocol-and frequency-specific base station radios. Hypres technology will conceivably expand base station range coverage, enabling a significant reduction of the total number of base station sites required, thereby reducing total network capitalization and operating costs. In effect, Hypres technology enables wideband 4G performance with GSM-type base station range.
For an SDR configuration, significantly reduced longer-term network capitalization is also accrued due to much longer life cycles via the introduction of new and expanded services that take advantage of programmable RF components, minimizing future hardware changes.
Hypres claims their technology approach will reduce by at least 1/3 the number of cell sites needed per service area, reduce by at least 1/3 the RF equipment per cell site, and increase the system performance by more than +3dB.p>
Trango Systems, developer of high-capacity licensed and unlicensed fixed wireless microwave communication systems, exhibited their microwave systems for a wide range of telecommunications applications including WiMAX backhaul, 2G/3G/4G mobile/cellular backhaul, carrier Ethernet networks, rural broadband access municipal/government networks, and enterprise wireless network extensions, including leased line DS1/DS3/OC-3 replacement. Among the products highlighted were the licensed all-outdoor Ethernet-native RF microwave radio, TrangoLINK(TM) Apex; the licensed split-architecture Ethernet/TDM native RF microwave link system, TrangoLINK Giga(TM); and the unlicensed 5 GHz multi-band OFDM wireless Ethernet bridge, TrangoLINK-45(TM). The TrangoLINK Giga(TM) that is currently shipping in frequencies 6, 11, 18, and 23 GHz, will soon be available in ETSI standard versions, including 15 GHz. TrangoLINK(TM) Apex will be available in the same licensed frequencies and is now shipping the 18 GHz model. Company spokesmen told us that beginning this fall, both TrangoLINK Giga(TM) and TrangoLINK(TM) Apex will be available in ETSI European standard versions, starting with 23 GHz and 11 GHz models. TrangoLINK-45(TM) is ETSI certified and operates in multiple unlicensed bands: 5.2, 5.3, 5.4, and 5.8 GHz.