Wireless Systems Design

On The Wireless Front

Syracuse, New York
Anaren, Inc. recently announced that its Breakthrough 2003 launch represents a major improvement in balun transformers. This launch takes the form of a minuscule, surface-mount Xinger-brand component called a Femto balun (FB). At 0.12 × 0.12 × 0.035 in. (3.05 × 3.05 × 0.89 mm), it is by far the smallest Xinger-brand component ever introduced by the company. The Femto balun is ideal for next-generation 802.11 Wireless Local Area Network (WLAN) chip sets and Bluetooth platforms. In such applications, it elegantly replaces lesser-performing ceramic and lumped-element solutions. In addition to the obvious cost savings, the FB offers a 0.5-dB insertion loss, outstanding phase and amplitude balance, and a reduction in system power consumption. Plus, its return loss makes the unit "mismatch" tolerant.

The FB comes in two versions: the FB650 and FB850. Each version has a 2.4-to-2.5-GHz (narrowband), 5.15-to-5.35-GHz (narrowband), and 4.8-to-5.8-GHz (broadband) frequency range, respectively. Each device boasts a 17-dB return loss, a 180° ±5° (maximum) phase balance, and a power handling of 4 W.

These products mark the company's new foothold in consumer end products, such as WLAN, Bluetooth-equipped laptops, and wireless headsets. Traditionally, the company has been known as a component and subassembly supplier. Basically, it served large-scale wireless-infrastructure equipment OEMs in the base-station and space/defense arenas.

Like all Anaren off-the-shelf components, the new FB transformers are backed by the Anaren exclusive 100% OnSpec guarantee. In addition, the company's B-There service commitment ensures on-time delivery. Samples and application notes are available within 24 hrs. for qualified prototype work. For further details, go to www.anaren.com.

Santa Clara, California
Recently, National Semiconductor Corp. announced the LM4906 Boomer audio amplifier. This amplifier eliminates the bypass capacitor that is typically connected to the reference-voltage pin. This architecture improves the power-supply rejection ratio (PSRR) while providing very fast turn-on times. Both features are ideal for applications in small, portable devices, such as mobile phones and notebook computers.

The LM4906 Boomer product features a patent-pending architecture that does away with the need for the reference-voltage bypass capacitor. The result is a reduction in system cost and board-space savings. For customers, it offers savings in terms of manufacturing time. The product's fast turn-on and turn-off times also are very important for power consumption. They enable aggressive power management and longer talk time in cellular applications.

This audio amplifier is designed to improve overall system performance. It was created for demanding applications in mobile phones and other portable communication devices. It is capable of delivering 1 W of continuous average power to an 8-Ω bridge-tied load (BTL) with less than 1% total harmonic distortion plus noise (THD+N) from a 5-V DC power supply. The LM4906 has an internal selectable gain of either 6 or 12 dB. It does not require output-coupling or bootstrap capacitors.

The device contains advanced pop-and-click circuitry, which eliminates the noise that would otherwise occur during turn-on and turn-off transitions. The LM4906 also houses a low-power-consumption shutdown mode. This part is enabled by pulling the shutdown pin high. In addition, the product boasts an internal-thermal-shutdown protection mechanism.

The LM4906 is available now in either LLP chip-scale or MINI SOIC packaging. It is priced at $0.60 in 1000-unit quantities. More information on the LM4906 is available at www.national.com.

Mitchel Field, New York
Since its inception, Frequency Electronics, Inc. has worked to provide the most advanced control of frequency and time. Both of these factors are essential for communication and data transfer in electronic spacecraft systems, telecommunications networks, and certain military applications. Time and frequency also are used to synchronize voice, data, and video transmissions in wireless communications systems. These systems are found in both ground-based stations and on-board commercial satellites. Frequency Electronics' family of GPS clocks was created with all of these uses in mind.

Featured in this family are clocks characterized by 1 PPS operating at 10 MHz, 13 MHz, 15 MHz, or any other desired output frequency that is derived via DDS. The clocks are available in various disciplining hierarchies, including GPS > Rb > Rb, GPS > Rb > Quartz, Rb > Quartz, and GPS > Quartz. Various packages allow the company to satisfy customer requirements. For further information on the GPS clock family of products, point your browser to www.freqelec.com.

Milpitas, California
Linear Technology Corp. now offers the LTC3441—a true buck-boost DC/DC converter. This converter can deliver up to 1 A of output current at efficiencies as high as 95%. The LTC3441, a synchronous, fixed-frequency converter, is designed to optimize battery run time for single-cell Li-Ion, multi-cell alkaline, or NiMH battery-powered applications. It operates from an input voltage range of 2.4 to 5.5 V. The LTC3441 can provide up to 1 A of output current at a fixed output voltage falling between 2.4 to 5.25 V.

This converter's buck-boost topology allows it to operate above, below, and equal to the output voltage with a single inductor. This capability provides a continuous transfer function through all of the operating modes as the battery voltage declines. The operating frequency is set internally to 1 MHz. It can be synchronized up to 2 MHz, at which point tiny surface-mount components may be used.

As an added benefit of the LTC3441, the switching noise can be maintained well above the pass-band of most communication systems. The small implementation footprint makes it ideal for space-constrained environments, such as cellular phones, PDAs, wireless and DSL modems, and digital cameras.

The LTC3441 uses two 0.10-Ω n-channel and two 0.11-Ω p-channel switches in a constant-frequency, synchronous switching topology. As a result, it can obtain efficiencies as high as 95%. Its selectable burst-mode operation allows the internal power MOSFETs to operate intermittently based on load demand. It also reduces the quiescent current to a low 25 µA when there is no load (less than 1 µA in shutdown). Furthermore, the selectable burst-mode operation is inhibited during synchronization or when the SYNC/MODE pin is pulled low. This prevents low-frequency ripple from interfering with audio circuitry.

The LTC3441 features anti-ringing control to minimize EMI, soft-start control, and thermal shutdown. It is available now from stock in a 4-×-3-mm, DFN-12 package. Pricing starts at $3.55 each in 1000-piece quantities. For further details go to www.linear.com.

Basel, Switzerland
At the recent Ineltec conference and exhibition in Basel, Switzerland, HUBER+SUHNER presented several advances in antenna design. Included in these announcements were new solar connectors and the intelligent fiber-optic distribution system known as LISA. The company also went public with an ultra-broadband indoor SENCITY ART antenna.

According to HUBER+SUHNER, these advances are being driven by a number of different factors. Perhaps most significant is the market need for an antenna design that will allow the transmission of nearly all currently used wireless frequencies. This ambitious requirement is achieved through the company's SENCITY ART product. It covers all frequency ranges from 800 MHz to 6 GHz (UMTS, GSM, and WLAN). Specific antenna solutions also are available for indoors and tunnels as well as Fiber-to-the-Antenna. These antennas complete the company's product portfolio.

The problematic nature of cable management also plays into these product releases. To deal with this issue, HUBER+SUHNER has created its Leading Interconnect Systems Approach (LISA). This intelligent, passive fiber-optic distribution system is designed for telecom and LAN applications. It is complemented by the company's comprehensive distribution solutions, including main distributors, cable ductings, outer housings, closures, and distribution wall boxes.

For further information on any of these specific product announcements or for details on the company's ongoing developments, go to www.hubersuhner.com.

Calgary, Alberta, Canada
The Institute of Navigation (ION) and the National Aeronautic Association (NAA) have selected NovAtel, Inc. to develop a global positioning system differential system. This system will be used by the NAA in establishing straight-course speed records for aircraft in flight. The GPS Flight Recorder system is expected to be complete by May 2004. The use of space-based satellite systems and carrier phase processing, like the system being developed by NovAtel, is expected to provide microsecond course-time-measurement precision.

One of the primary functions of the NAA is to encourage, coordinate, document, and promote competition and record-making aviation and space events. The NAA performs these functions in accordance with the rules prescribed by the Federation Aeronautique Internationale (FAI), for which it is the official U.S. representative. The FAI Sporting Code requires a 0.25% overall system accuracy in the measurement of record speed over a 3-km course. As speeds increase, the time needed to traverse the 3-km course decreases. It then becomes impossible to assure the required 0.25% system accuracy using hand-timing techniques. Overall, as aircraft performance improves, the measurement of these types of records becomes equipment and manpower intensive. A GPS system, such as the one to be supplied by NovAtel, could significantly reduce the equipment costs and manpower that are currently required for these records.

Further information on this project can be found at www.novatel.com.

Greensboro, North Carolina
RF Micro Devices recently celebrated the shipment of 250 million power-amplifier (PA) modules. This news is viewed as further proof of the company's position as one of the world's leading PA providers for handsets. In part, this success is due to its proven design and manufacturing expertise, as well as the strength of its PowerStar products. Patent-pending PowerStar solutions have helped RFMD become the leading supplier of PAs for the GSM air-interface standard. This standard accounts for approximately two-thirds of the world's cell phones.

Of particular interest is the company's RF3146 next-generation PowerStar PA module with integrated power control. It is based on the company's new, patent-pending Lead Frame Module packaging technology. The RF3146 promises customers improved performance, reduced product size, and lower cost. At the same time, the company's packaging technology helps streamline the manufacturing process. As a result, the modules experience improved margins.

For more information about RFMD or its power-amplifier products, visit www.rfmd.com.

Souderton, Pennsylvania
Amplifier Research (AR) now has a new family of broadband solid-state products. The first two amplifier products in this family are the 5S4G11 and the IS4G11. Both of these products satisfy the need for low-power applications up to 10.6 GHz. In fact, they are the only solid-state amplifiers for laboratory and EMC testing with a bandwidth of 4.0 to 10.6 GHz. These products—and the higher-power versions that will follow—are expected to set new standards for microwave solid-state amplifiers.

The AR Model 5S4G11 product is a solid-state, self-contained, air-cooled broadband amplifier. It delivers a minimum of 5 W of RF power when used with a sweep generator. Its frequency response is 4.0 to 10.6 GHz instantaneously. As specifications and requirements demand higher frequencies, users thus have room to grow. This family of solid-state amplifiers is ready to meet emerging standards.

In addition to its frequency response, the 5S4G11 has some very impressive specifications. It boasts a power output at 3-dB compression of 7 W (nominal), 5.5 W (minimum); a power output at 1-dB compression of 6 W (nominal), 4.5 W (minimum); and a flatness of +2.0 dB (typical).

Additionally, it flaunts a gain of 37 dB at maximum setting and a harmonic distortion of -20 dBc (maximum) at 5 W.

Amplifier Research also is introducing the Model 1S4G11 broadband amplifier. With features that resemble the 5S4G11, it provides a minimum of 1 W of RF power when used with a sweep generator.

For more information, go to Amplifier Research's Web site, located at www.amplifiers.com.

Columbia, Maryland
The flexComm Software Defined Radio (SDR)-3000 from Spectrum Signal Processing (USA), Inc. will soon be put to military use. This family of software reconfigurable platforms will be utilized by the U.S. Department of Defense Joint Tactical Radio System (JTRS) Joint Program Office (JPO). The JTRS JPO's test and certification element, called the JTRS Technology Laboratory (JTeL), came out with this announcement. Its choice verifies that the U.S. Department of Defense will use the SDR-3000 architecture for the independent verification and validation of JTRS waveforms. Specifically, the architecture will fulfill the following purposes:

  • Software Communications Architecture (SCA) acceptance and compliance testing of JTRS waveforms
  • Support of the advancement of the Software Communications Architecture
  • To provide growth capabilities for the acceptance and compliance testing of future JTRS waveforms

Spectrum Signal Processing also will provide its flexComm SDR-3001 development platform to JTeL, which is part of the U.S. Navy's Space and Naval Warfare Command. In addition, the company will supply software-engineering services. These services will support the porting and testing of waveforms that were developed for JTRS by U.S. defense contractors.

As a result of these five JTRS cluster contracts, a family of software-programmable radios will be designed around the SCA. This radio family will ensure interoperability and portability across disparate radio networks. Joint tactical radios will be multi-mode and multi-band, allowing one radio to communicate with numerous other radios. These aspects also will allow the over-the-air programming of those sets. The new radios will carry information in real-time to the warfighter in the field. It won't matter if that soldier is ground-based, stationed onboard a ship, or airborne. Once it's fully implemented, JTRS will enable the information superiority that will be needed for more effective military engagements.

The flexComm SDR-3001 SDR Development Platform comprises a heterogeneous processing platform. That platform incorporates Xilinx FPGAs, PowerPC processors from Motorola, and Texas Instruments' DSPs. It also houses an integrated radio-frequency transceiver and analog I/O module.

For more information on this contract or development effort, go to www.jtrs.army.mil or www.spectrumsignal.com.

Sunnyvale, California
Maxim Integrated Products just introduced its MAX5858, a dual, 10-b, 300-Msps DAC that flaunts integrated digital interpolation filters. The device integrates two 10-b DAC cores, 2x/4x programmable digital interpolation filters, a divide-by-N clock output, and an internal reference. It also features digital control of channel gain matching to within ±0.4 dB in 16 0.05-dB steps.

The device is specified over the 2.7- to-3.3-V operating range and an extended output compliance voltage. Consequently, it delivers outstanding dynamic performance. At a 20-MHz output frequency (165-MHz sample rate), the spurious-free dynamic range (SFDR) is 75 dBc. The adjacent-channel leakage ratio (ACLR) is 69 dBc when the output frequency is 30.7 MHz (3.8-MHz channel).

The integrated interpolation filters separate the generated images. They make the analog filter following the DAC both cost-effective and easy to design. In addition, the interpolation filters lower the input data rate and reduce the inherent DAC rolloff.

This combination of excellent performance and on-board interpolation filters makes the MAX5858 ideal for communication systems. For example, it would be well suited to point-to-point microwave links, LMDS, MMDS, WLAN base stations, and VSAT terminals.

The MAX5858 DAC is the lead product in a family of high-performance DACs. It is available in a space-saving, 48-pin TQFP package specified for the industrial temperature range (-40°C to +85°C). Prices start at $11.80 (1000-up). An evaluation kit is available to speed designs. For further information on this product, go to www.maxim-ic.com.

Indianapolis, Indiana
JFW Industries' latest innovation in programmable attentuation is the 50P-1501 SMA. It offers solid-state reliability from 300 to 3000 MHz and 127 dB of dynamic range. This product also flaunts 1-dB resolution with attentuation steps of 1, 2, 4, 8, 16, 32, and 64 dB. With these features, the device is ideal for Original Equipment Manufacturer (OEM) or laboratory applications in any general wireless system. TTL control and SMA female connectors are standard in this device. Additional characteristics include 50 Ω impedance (nominal); a VSWR of 1.5:1 maximum; and an insertion loss of 3.5 dB (maximum) to 1000 MHz and 6.0 dB (maximum) to 3000 MHz. The RF input power is +20 dB (operating), while the switching speed is 2 ms (maximum).

The 50P-1501 SMA device is powered by +5 Vdc at around 300 mA (nominal). It has an operating temperature of 0°C to +70°C.

For further information on the JFW Industries programmable-attentuation device, point your cursor to www.jfwindustries.com.

Springfield, Virginia
Nearson now offers a number of different antenna product lines for IEEE 802.11a WLAN applications. The 151 Series Antenna, for example, boasts a frequency of 5.15 to 5.35 GHz colinear and a gain of 5 dBi. Its length is 7 in. with an SMA TNC connector. It flaunts a straight, right-angle design. The 152 and 181 Series antenna products mimic these same characteristics. But they each have a length of just 5 and 4 in., respectively.

By contrast, the 611 Series antennas have a frequency of 5.15 to 5.35 GHz microstripe and a gain of 5 dBi. Just 4.25 in. in length, this line features flying lead with MMCX connectors and a fixed-mount, right-angle style.

Further details on these products can be found at www.nearson.com.

San Diego, California
Ethertronics has recently come to market with a new family of quad-band internal antennas. This announcement means that IEEE 802.11 a/b/g wireless local area network (WLAN) products can now use all available worldwide WLAN frequencies (2.4, 4.9, 5.2, and 5.8 GHz). In particular, this family covers areas like the Americas, Europe, Asia, and Japan. According to the company, these quad-band internal antennas stand out because of their superior range and data-rate performance, delivered in a very small form factor.

The internal antennas are available in two configurations. The first is a single, surface-mountable, antenna-component configuration. It is currently ready for automated, high-volume assembly. The second configuration is a complete module. By providing an antenna, connectors, and cable, it simplifies mounting and integration. This latter option is ideal for the mini-PCI applications in notebook computers.

The antennas are among the company's most advanced products to date, offering the user a unique blend of technology. Miniature size, high efficiency, and superior isolation properties are the hallmarks of these innovative antennas. They can be placed very close to surrounding components in a variety of applications without sacrificing any performance. The flexilibity of the products' design dramatically simplifies integration in notebook computers, handheld devices, and personal-computer cards. Contact the company for pricing and availability information. Point your web browser to www.ethertronics.com.

West Caldwell, New Jersey
Merrimac Industries, Inc. has received orders totaling $2.1 million from Raytheon Integrated Defense Systems. Under terms of the agreement, Merrimac will provide a variety of signal-processing products that will be used in Raytheon's X-Band Radar (XBR) program.

XBR is a high-powered, phased-array radar that is designed to meet near-term ballistic-missile threats from rogue states. It is a key element in the Missile Defense Agency's ground-based Midcourse Defense system. For its part in that system, this large, phased-array fire-control sensor features precision discrimination and interceptor support.

To be chosen to participate in the SBR program, Merrimac provided designs that enhanced the overall performance of Raytheon's XBR system. In addition, the company demonstrated "production readiness" to meet Raytheon's delivery requirements.

For more information on this project, or for additional details on either company's core technology—signal processing products or XBR—point your cursor to www.merrimacind.com or www.raytheon.com, respectively.

Dallas, Texas
Texas Instruments (TI), Inc. just announced a highly integrated, feature-rich, battery-charging and power-conversion IC. It delivers unmatched levels of high performance and power conversion efficiency up to 97%.

The 7 mm × 7 mm TPS65010 power IC leverages TI's 3307A12 manufacturing process technology. As such, it occupies up to three times less board space when compared to discrete solutions with similar levels of functionality. The device integrates two synchronous step-down DC/DC converters with integrated FETs, one 1-A converter for system voltages, and one 400-mA converter for processor cores. It deploys pulse-frequency modulation and pulse-width-modulation switching technology. Additionally, it provides an extremely low quiescent current of 70 µA and several low-power modes. The IC also incorporates two 200-mA low-dropout (LDO) regulators for additional voltage generation.

The TPS65010 is available now. Packaged in a 48-lead QFN package, its suggested resale pricing is $4.99 per unit in quantities of 1000. For more information on this product, go to www.ti.com.

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