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ISSUE DATE: DECEMBER 2009 | |
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December 2009 - In This Issue [Cover Story] Top Products Of 2009 Launching a new product can be thrilling as well as stressful. Introducing a new product to the RF/microwave industry, after all, is the “moment of truth” in which all that market research, technology, and engineering comes together to be judged by the industry at large. Having a product reviewed in the pages of magazines such as this is one form of recognition of a product’s worth; being named to the list of Top Products of The Year is one indication that a product is making its mark in... — Jack Browne , et al. [News] Medical And Smart-Grid Markets Beckon Designers Microwave companies have largely weathered the current recession with grace, thanks to steady military requirements and evolving communications markets. Those markets have offered microwave firms new opportunities supporting fourth-generation (4G) wireless systems, unmanned aerial vehicles (UAVs), and improvised-explosive-device (IED) detection. Yet high-frequency technology also is viewed as a solution for nontraditional markets, such as the medical and smart-grid areas, as a means of... — Nancy Friedrich [News] Taking Measure Of Microwave Mixers Microwave mixers are widely used in commercial and military electronic systems for frequency conversion. They are essential for shifting the frequency of a signal downward (downconversion) or upward (upconversion) as might be needed in a receiver and transmitter, respectively. By understanding some fundamental concepts about mixer operation and performance, specifying a mixer for an application can be greatly simplified. A frequency mixer is a three-port component, with two ports... — Ferenc Marki , et al. [Design Features] Class F Amplifier Boasts High Efficiency Pulsed radar systems require high power levels but, increasingly, also demand power amplifiers with high efficiency. To meet those needs at L-band frequencies from 1200 to 1400 MHz, a Class F amplifier was developed with reduced conduction angle to maximize efficiency. The amplifier employs four parallel, internally matched silicon-bipolar transistors in a common-base configuration. They are biased in Class C mode to achieve the high output power levels required by pulsed radar systems.... — Sami Bousnina , et al. [Design Features] Triband Cellular Antenna Tackles E-Field Testing Antennas for wireless applications must handle more bands than ever before, given the growing number of cellular and other wireless standards contained in handsets and base stations. In support of measurements to be performed on cellular base stations, the authors have implemented a printed-circuit dipole antenna on a two-layer RO4350B laminate from Rogers Corp. The compact printed antenna covers cellular bands at 900, 1800, and 2100... — Dimitris Kolokotronis , et al. [Design Features] Microwave Materials Lay Foundation For PAs Power-amplifier designers typically create a circuit based on specific active devices for the output stage. While the choice of transistor determines the ultimate performance of an amplifier, printed-circuit-board (PCB) materials can also play a major role in an amplifier design. Selecting optimum substrate materials for an amplifier can improve gain and stability, and enable the maximum output power possible for a design. High-frequency amplifier designers have a wide array... — John Coonrod [Design Features] Examine Antenna Tunability In Implanted Systems Electronic devices are increasingly being implanted inside the human body to improve medical diagnostic or therapeutic efficacy. Fine tuning these devices requires communications with medical professionals, yet direct communications are problematic due to the locations of these systems within the body. A growing trend has been to communicate with these systems by means of wireless RF transceivers. Care must be taken when designing an antenna for such systems as canonical antenna design methods... — Mark Lanciault , et al. [Product Technology] Mixers Terminate Intermod Distortion Minimizing intermodulation distortion (IMD) in mixers can benefit many commercial and military RF/microwave systems. For that reason, Marki Microwave has developed its two-tone-terminator (T3) line of mixers for superior suppression of two-tone IMD. The T3 mixers cut conversion loss to typically only 7 dB from 10 MHz to 12 GHz, with input third-order intercept (IIP3) points that are typically 10 dB (and as much as 20 dB) higher than the local oscillator (LO) drive level. Conversion loss is... — Ferenc Marki , et al. [Product Technology] Surface-Mount Mixers Are WJ Replacements Replacing a discontinued component, such as a mixer, in an existing design can pose challenges when a trusted part is no longer available. Fortunately, in the case of broadband surface-mount mixers from Watkins-Johnson and, until recently, offered by TriQuint Semiconductor (), a number of miniature packaged passive diode mixer models from Mini-Circuits serve as excellent... — Jack Browne [Product Technology] Downconverting Mixers Range Wide To 4 GHz Active frequency mixers offer conversion gain where needed, but often represent a compromise in dynamic performance. Those traditional tradeoffs can be neglected. However, in the case of the LTC554x family of passive downconverting mixers from Linear Technology, they combine low noise figures with high input third-order intercept points to achieve outstanding dynamic range from 700 MHz to 4 GHz. The LTC554x family of mixers... — Jack Browne [Product Technology] VME/VXS Cards Capture Agile Signals Signal capture is an essential part of many military and intelligence systems. With suspect signals lurking within increasingly dense signal environments, high-speed digitizers are needed for reliable signal acquisition and processing. Fortunately, the Acqiris models SVM3500 and SVM4800 VME/VXS format digitizers from Agilent Technologies provide the signalprocessing firepower needed to grab as many... — Jack Browne [Product Technology] 2009 Editorial Index COMMERCIAL •Crosstalk With The Unknown Editor (January, p. 42))) •Crosstalk With Alexander Chenakin(March, p. 38))) •Achieving Effective Amplifier Designs (May, FOCUS, p. S8))) •Crosstalk With Vinod Chitkara (August, p. 44))) •Microwave Legends (August, p. 47))) • Crosstalk With Eric Strid (September, p.... — Jack Browne [Editorial] ’Tis The Season To Send Data This holiday season, iPhones are at the top of many wish lists. People want to be able to take videos or pictures of their kids opening presents, for example, and upload them to Facebook right away. Yet as more smartphones are purchased by consumers, a problem arises: Cellular networks simply are not prepared to handle this amount of data. In the near future and beyond, this need promises headaches for carriers but opportunities for firms with solutions that raise... — Nancy Friedrich [Feedback] Feedback Software Reviews Needed Your comments in the November 2009 editorial on free design software struck a resonant chord in my company, since we operate with limited resources and cannot afford to equip every engineer who would so chose it to have a seat on our full-function microwave simulator of choice. For that reason, we are often experimenting with freeware and other low-cost options, especially when evaluating part of a... — Various Readers [The Front End] China’s Wireless-Infrastructure Equipment Spending Peaks In 2009 EL SEGUNDO, CA—China’s massive spending on third-generation (3G) networks by its three mobile carriers—China Telecom, China Unicom, and China Mobile—will cause spending on wirelessinfrastructure equipment in the nation to surge by 27.7 percent. Spending will reach $6.3 billion in 2009, which marks a peak for expenditures according to iSuppli Corp. China’s three mobile carriers completed the first phase of their... — Dawn Hightower [The Front End] WCAI Launches Effort To Unlock 3.65-GHz Band’s Potential WASHINGTON, DC The Wireless Communications Association International (WCAI) has launched an industry-led effort to unlock the potential of the 3.65-GHz band by addressing its remaining regulatory and technical challenges. Specifically, the association formed the 3.65-GHz Working Group to develop a synchronization protocol in the band, which will promote coordination and mitigate harmful interference among operators. The working group also is tasked with... — Dawn Hightower [The Front End] Glasgow Scientists Guide Future Nano-Chip Design GLASGOW, SCOTLAND—In collaboration with colleagues from Edinburgh, Manchester, Southampton, and York universities, scientists at the University of Glasgow have developed technology to help microchip designers create future integrated circuits (ICs). Essentially, the scientists have developed simulation tools that take advantage of grid computing to predict how billions of nano-transistors—each with their own unique and unpredictable atomicscale ... — Dawn Hightower [Financial News] Agilent Acquires Keithley Product Line Agilent, Keithley, have announced the completion of the sale of substantially all of Keithley’s radio-frequency product line to Agilent, which is based in Santa Rosa, CA. The parties had signed a definitive agreement for the approximately $9-million sale on November 19. With the completion of the sale, the majority of the Keithley RF team of about two dozen employees in Santa Rosa will become Agilent employees. In addition, Agilent will provide... — Dawn Hightower [Company News] Company News Contracts Herley Industries, Inc.—Has announced that its Herley-CTI subsidiary located in Whippany, NJ has received an award for an indefinite-delivery/indefinite-quantity (ID/IQ) contract valued at approximately $8.5 million from a major US prime contractor. The firm will manufacture fast-switching synthesizers for a radar system application. This six-year agreement is a follow-on to previous development and... — Dawn Hightower [People] People Raytheon Engineer Receives National Award DR. PIALI DE has received a national award for Technology Innovation at the 2009 Women of Color’s 14th Annual Conference. De is a Raytheon engineering fellow in Civil Security and Response Programs at Raytheon Integrated Defense Systems (IDS). She is one of two recipients of this year’s Technology Innovation award for innovation in science, technology, engineering, and math (STEM). Daniel L. Smith,... — Dawn Hightower [Educational Meetings] Educational Meetings Meetings 2010 IEEE Radio & Wireless Conference (RAWCON) Jan. 10-14, 2010 (New Orleans, LA) For more information, visit: www.radiowirelessweek.org IWCE March 8-12, 2010 (Las Vegas, NV) For more information, visit: www.iwceexpo.com 6th Annual International... — Dawn Hightower [R&D Roundup] Determine Radiation Effects For Ingestible Wireless Devices To assess the compliance of an ingested wireless device (IWD) with related international safety guidelines, a team of researchers used the finitedifference- time-domain (FDTD) method for two realistic body models in an electromagnetic (EM) simulator. Both biological effects and the IWD’s signal intensity were studied by Lisheng Xu from China’s Northeastern University together with Max Q.H. Meng, Hongliang Ren, and Yawen Chan from the Chinese University of Hong... — Nancy Friedrich [R&D Roundup] 1.8-GHz Synthesizer Is Based On MEMS Resonator To implement critical functions, many highperformance systems rely on fully integrated passive elements with relatively limited performance. Often, such components are combined with higher-quality off-chip devices that implement specific key functions. An alternative may exist in solutions based on microelectromechanical systems (MEMS). At Montreal’s McGill University, an integrated and digitally programmable synthesizer that uses a MEMS resonator as its reference... — Nancy Friedrich [R&D Roundup] Miniaturized UWB Antennas Cover Large Bandwidths Often, several antennas are used to cover a large operational bandwidth encompassing numerous communications systems. Yet it can be quite difficult to integrate multiple antennas into a platform because of complications like payload restrictions, limited space, cost, and electromagnetic compatibility/ interference (EMC/EMI). At The Ohio State University, a team of researchers worked to address this problem by reviewing the physical limitations of antennas. More... — Nancy Friedrich [Application Notes] GaN Enables High-Power Wideband Designs For next-generation broadband amplifier designs, many engineers are now looking at gallium-nitride (GaN) device technology as an option. Yet some debate still exists about whether GaN high-electron-mobility-transistor (HEMT) technology is a viable option compared to gallium-arsenide (GaAs) field-effect transistor (FET) and silicon laterally diffused metal-oxide semiconductor (LDMOS). In the application note titled, “AN-013: Broadband Performance of GaN HEMTs,”... — Nancy Friedrich [Application Notes] Signal Generator Produces Above +30 dBm Output Power To 20 GHz If a signal generator can deliver a pure, accurate signal at a sufficient power level, the instrument ensures improved measurement accuracy. It also enables testing with greater dynamic range and at extreme or unusual operating conditions. In a five-page application note titled, “Generating and Applying High-Power Output Signals,” Agilent Technologies explains how its E8257D PSG analog signal generator can deliver capabilities that include at least +25 dBm... — Nancy Friedrich [Editor's Choice] Attenuators Control Amplitude From 6 To 16 GHz MANY TYPES OF ATTENUATORS have evolved to reduce a signal’s amplitude or power without overly adding distortion. For example, a recent example of a broadband digital attenuator is the model DAT-23-480/2S. This 8-b attenuator covers 6 to 16 GHz with attenuation range of 0 to 64 dB and least-significant bit (LSB) of 0.25 dB. It exhibits insertion loss of 6 dB or less and maximum VSWR of 2.0:1. The attenuator typically switches in 500 ns. It provides ±1.2 dB flatness at its... — Nancy Friedrich [Editor's Choice] Green-Friendly XO Runs On As Little As 0.8 V TO PAVE THE WAY to eco-friendly mobile products, a new miniaturized crystal oscillator (XO) promises to increase battery life. The 2.5-x-2.0-x-0.9-mm NZ2520SF is available with frequencies from 1.5 to 50 MHz with a stability of ±50 ppm. It operates on as little as 0.8 V, which is reportedly 50 percent lower than comparable XOs. A 40-percent reduction in current draw allows the NZ2520SF to deliver a 70 percent reduction in power consumption with corresponding extended... — Nancy Friedrich [Editor's Choice] Up-/Downconverting Mixer Covers 2000 To 3000 MHz AN UP-/DOWNCONVERTING MIXER has debuted for base stations that demand high linearity and a low noise figure, such as Long Term Evolution (LTE), WiMAX, WCS, and MMDS. The MAX2042 covers 2000 to 3000 MHz. When it is configured as a downconverter, this silicongermanium (SiGe) passive mixer features an intermediate-frequency (IF) range of 50 to 500 MHz with 1800-to-3000-MHz local-oscillator (LO) signals. As a downconverter, it provides a +36-dBm input third-order... — Nancy Friedrich [Microwaves in Europe] Developments Drive Innovation In Low-Energy Bluetooth And Wheelchair Communications Silicon Samples Arrive For Low-Energy, Single-Mode Bluetooth Solutions IN TRONDHEIM, NORWAY, Nordic Semiconductor has started shipping silicon samples and development kits of the first member of its Blue Bluetooth lowenergy single-mode solution, the nRF8001, to key customers. Although the Bluetooth low-energy specification is still under development, Nordic is providing a... — Paul Whytock |
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