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ISSUE DATE: JULY 2010 | |
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July 2010 - In This Issue [Cover Story] SMT Couplers Build On Legacy Generational improvements in product lines are often incremental in nature, especially for passive components. But for the third generation of Xinger hybrid and directional couplers from Anaren, the improvements from the first- and second-generation products are dramatic, with significantly less insertion loss and greatly improved power-handling capability per square inch. The new patent-pending Xinger- III... — Jack Browne [News] Channeling Power In MW Components Handling large amounts of RF/microwave power is part science, part imagination. The science exists in the form of thermal flow equations and thermalmechanical design software programs to calculate temperature rises in a wide range of electronic materials based on input power levels, dissipative and radiative losses, and thermal conductivity, among other parameters. The imagination helps to visualize the thermal flow through a system and,... — Jack Browne [News] Satellite Markets Enjoy An Uptick The term “satellite” conjures many images ranging from television service to cutting-edge military applications like the “mystery” satellites that provide surveillance over troubled areas. With so many automobile drivers equipped with Global Positioning Satellite (GPS) systems, however, satellite applications have become rather commonplace. Yet that does not mean they have lost their innovative edge. Emerging needs continue to open new markets and ... — Nancy Friedrich [News] Raise Awareness Of Satellite Interference — Robert Ames [Design Features] X-Parameters Aid MMIC Design The most common method to accurately characterize RF/microwave components under linear conditions has been through the use of S-parameters. However, modeling nonlinear behavior of certain components, such as amplifiers and mixers, is challenging because S-parameters cannot be applied effectively and accurately under large-signal conditions. Approximation techniques have been used for modeling nonlinear behavior—with partial success— by... — Jack Sifri [Design Features] Reviewing Avionics Antenna Modules, Part 2 A ntenna modules provide system integrators with a means of saving weight and volume in an airborne avionics platform. As mentioned in Part 1 of this article in June 2010 Microwaves & RF (see. p. 72), combination Traffic Collision and Avoidance System (TCAS) and Transponder suites used on many aircraft rely on four different antennas, ten cables, and separate ... — Leo G. Maloratsky [Design Features] Modeling PA Behavior And Memory Effects, Part 2 Developing a behavioral model for power amplifiers with memory effects requires including nonlinear phenomena. As shown in Part 1 (Microwaves & RF, June 2010, p. 84), nonlinear amplifier behavior is usually characterized by AM-AM and AM-PM conversion. As will be shown in Part 2, models incorporating these effects can be validated by the appropriate measurements. ... — [Design Features] Wideband Limiter Fits SOT-323 Pack Limiters protect wireless receiver front-ends from irreversible damage due to signal overload. By combining Schottky and PIN diodes in a hybrid limiter design that can be mounted in a compact SOT- 323 surface-mount package, it has been possible to develop a low-cost limiter with 1 dB or less insertion loss from 10 MHz to 1.7 GHz with an input-power turn-on threshold (PTH) of only +2 dBm at 450 MHz. To the authorâ??s knowledge, this is the first ... — Chin-Leong Lim [Design Features] Form Microstrip Couplers With Shielded Membranes Membrane-supported transmission lines and circuits are excellent candidates for millimeter-wave applications where conventional substrate-supported architectures begin to suffer from parasitic effects at the dielectric/ air interface.1-3 Transmission lines based on the technology, known as shielded-membrane-microstrip (SMM) transmission lines, have been used to realize an asymmetric tapered coupled-line coupler operating from 10 to 60... — Nasreddine Ben Ahmed , et al. [Design Features] Front End Fits SDR Picocells Software-defined-radio (SDR) approaches are being used in compact cellular base stations, including in picocellular systems serving small areas such as onboard commercial aircraft. Wireless communications systems onboard an airplane must provide high-quality audio, video, and data services conveniently but without interference with the aircraft’s navigation systems. As a result, a picocell solution must perform with sufficient suppression of... — Wei Hong , et al. [Product Technology] Measuring MIMO Performance Levels Communications systems designers have reached for a variety of different techniques to squeeze maximum capacity from minimum bandwidths. One of these approaches involves the use of multiple signals as part of a multiple-input, multiple- output (MIMO) antenna configuration. MIMO techniques are used in a number of newer wireless standards, including in IEEE 802.11n wireless local area networks (WLANs), IEEE 802.16-2004 Fixed WiMAX, IEEE 802.16e Mobile... — Jack Browne [Product Technology] Transceiver IC Tackles 3G, LTE Mobile handsets must pack a great deal of functionality within a compact package to even approach modern customers’ expectations. In order to handle different bands and operating modes, RF front-end modules (FEMs) typically employ low-noise amplifiers (LNAs) and filters for each receiver band, and power amplifiers (PAs) and filters for each transmit band. But Fujitsu Microelectronics America has... — Jack Browne [Editorial] The Post-IMS Report Card Over the last couple of years, smart phones have become critical platforms for the use of maps and navigation. Now, those devices are beginning to propel the market for location-based services (LBSs). Currently, for example, Apple’s iPhone already has more than 6000 LBS applications available. With manufacturing costs in China set to rise, however, smart-phone makers will soon be pressured to adapt their manufacturing needs to a changing global economy. According... — Jack Browne [Feedback] Feedback Author’s Response I thank Mr. Polivka for reading my paper (“Reader Feedback,” June, p. 13). Yet I’m concerned that Mr. Polivka does not understand the arrangement of my rectenna (Fig. 1). I’m not sure why he is talking about single phase and efficiency of 50 percent. In this paper, we have done new research and it is not a copy of ref. 14. It should be noted that refs. 7 and 15 provide an RF conversion efficiency of about... — Various Readers [The Front End] SDR/CR Technologies Rev Up Wireless Prospects MOUNTAIN VIEW, CA—R&D efforts for radio communications are being intensified as defense establishments realize their personnel’s need for the latest generation of tactical radios. Software-defined radio (SDR) is expected to evolve into cognitive radio (CR), which could potentially transform future communications. In the US, both SDR and CR technologies are poised to replace legacy hardware in the defense domain with the deployment of radio systems that ... — Dawn Hightower [The Front End] ULP DECT Raises Acceptance Of Wireless Sensor Networks THE NETHERLANDS—A technology that has been commercially available for more than 15 years is now gaining momentum in the growing home-automation, control, and security network industry. With the recent development of the Digital Enhanced Cordless Telephone (DECT) ultra-low-power (ULP) operating mode, the technology is nourishing the market for battery-powered wireless sensor/actuator networks. The development of DECT ULP was spearheaded by RTX Telecom ... — Dawn Hightower [The Front End] Home Energy Is Managed With Mobile Phone CAMBRIDGE, UK—A recent demonstration from ip.access and AlertMe.com showed how femtocells can be integrated into smart-home energy-management solutions. With femtocell integration, the AlertMe Energy service can automatically detect when the house is empty and power down lights, televisions, and other home appliances. The service also can switch the services back on when the resident returns home. For the demo, ip.access combined the AlertMe Energy... — Dawn Hightower [Financial News] Boeing To Acquire Argon ST The Boeing Company and Argon have entered into an agreement whereby Boeing will acquire Argon ST in an all-cash tender offer and merger for $34.50 per share, or approximately $775 million, net of cash acquired. This acquisition is expected to advance Boeing’s growth strategy while expanding its capabilities to address the command, control, communications, computers, intelligence, surveillance, and reconnaissance (C4ISR), cyber, and intelligence... — Dawn Hightower [Company News] Company News CONTRACTS OEwaves—Has received an award from DARPA to investigate GMTI radar feasibility for the WASP unmanned aerial vehicle (UAV). Using the Whispering Gallery Mode (WGM) optical resonator technology, OEwaves developed and demonstrated a compact and lightweight transmit/ receive capability. The firm’s microwave photonic technology simplifies the architecture of conventional microwave techniques by addressing the... — Dawn Hightower [People] People Bisco Industries Names Wagner President DONALD S. WAGNER has been appointed President of Bisco Industries, Inc., a wholly owned subsidiary of EACO Corp. Wagner has served as the firm’s Chief Operating Officer and Executive Vice President since November 2007. He will continue to serve people as COO after his promotion. Wagner has served Bisco in a number of other capacities including Vice President of Product Management since June 1994. Prior... — Dawn Hightower [Educational Meetings] Educational Meetings MEETINGS ASQED10, International Symposium and Exhibits On Quality Electronic Design Aug. 3-4, 2010 (Penang, Malaysia) For more information, visit: www.isqed-asia.org. E-mail: info2010@isqed-asia.org European Microwave Week Sept. 26-Oct. 1, 2010 (Paris, France) For... — Dawn Hightower [R&D Roundup] Tri-Band Monopole Antenna Covers WiMAX And WiFi Bands Systems with mulitple wireless communications protocols require compact, low-cost, multiband antennas. Recently, a compact tri-band monopole antenna was proposed. It uses reactive loading, which was inspired by previous transmission-linemetamaterials (TL-MTM) work, and a “defected” groundplane. In doing so, it can meet the specifications of the WiFi and WiMAX standards while maintaining a small form factor. The antenna was developed by Jiang Zhu, Marco A.... — Nancy Friedrich [R&D Roundup] DDS RFIC Performs Direct Digital Modulation With the increasing availability of ultra-highspeed digital-to-analog converters (DACs), a direct digital synthesizer (DDS) can generate waveforms exceeding 1 GHz. Until now, however, no higheroutput DDSs have been able to provide the desired modulation capabilities. Now, what is thought to be the first DDS RFIC with greater than 1 GHz output and direct digital FM and PM capabilities has been presented by Xueyang Geng, Fa Foster Dai, J. David Irwin, and Richard C.... — Nancy Friedrich [R&D Roundup] 2.45-GHz Rectenna Transmits Power Wirelessly For energy-harvesting devices, the rectifying antenna (rectenna) is crucial. A broadband rectenna that uses a printed monopole antenna and bandpass stub bandpass filter has been developed by Tae-Ui Hong, Kyoung-Min Oh, Hyun-Wook Lee, Hee Nam, and Tae-Soon Yun from Seoul’s Kwangwoon University together with Dae-Sung Lee, Hak-In Hwang, and Jong-Chul Lee from the Korea Electronics Technology Institute. This antenna was designed at 2.45 GHz for the wireless ... — Nancy Friedrich [Application Notes] Use Diversity Techniques In Low-Power Radios The term "diversity" in radio systems refers to the use of multiple signal paths, such as in multipath conditions, as an advantage. The goal is to maximize the likelihood that a transmitted data packet will be correctly received. According to an application note titled “Implementing ‘Diversity’ Using Low Power Radios” by Mike Burns and Tim Starr, such techniques can be implemented using one or two low-power radios, a low-power microcontroller, and an ... — Nancy Friedrich [Application Notes] Grasp Ground Concepts In EM Simulators Many engineers do not understand how grounding is implemented in circuit simulation. As a result, electromagnetic (EM) simulators are often misused—with erroneous results. An 11-page white paper from AWR titled “Understanding Grounding Concepts in EM Simulators” defines ground connections in EM simulators. It also shows how to correctly choose among various grounding options. For example, many modern simulators support “local grounding,” whereby different ports ... — Nancy Friedrich [Editor's Choice] RMS Detector Provides 57-dB Dynamic Range To 10 GHz A 10-GHz RMS detector offers ±0.2-dB linearity over a 43-dB dynamic range at 2.14 GHz—even for signals with high-crest-factor modulation used in 3G and 4G broadband wireless networks. Dubbed the LTC5582, it vows to accurately measure signal levels as low as -56 dBm to +1 dBm to ±1 dB error. The RMS detector provides a 57-dB dynamic range from 450 MHz to 2.7 GHz. The device offers 46 dB of useful dynamic range at 6 GHz and 38 dB at 10 GHz. From... — Nancy Friedrich [Editor's Choice] Limiter Handles 10 W CW From 2 To 6 GHz To keep the RF input signals experienced by low-noise amplifiers (LNAs) and receiver frontend components to safe levels, a new limiter is designed to attenuate signals above a specific threshold. Dubbed model ACLM-4805FM15, this microwave limiter covers 2 to 6 GHz. It is rated to handle continuous-wave (CW) signal levels of 10 W and peak levels of 1 kW (1 µs pulse width, 0.1 percent duty cycle) over a temperature range of -55° to +85°C or 20 W CW and 1 kW peak at ... — Nancy Friedrich [Editor's Choice] 16-W GaAs FETs Cover 6.4 To 8.5 GHz The “EL” series of three galliumarsenide (GaAs) field-effect transistors (FETs) provides +42.5 dBm output power at 1-dB compression. The TIM6472-16EL operates from 6.4 to 7.2 GHz with 11.0 dB power gain at 1-dB compression and power-added efficiency (PAE) of 37 percent. Its sibling, the TIM7179-16EL, covers 7.1 to 7.9 GHz. It typically provides 10.5 dB power gain at 1-dB compression with 37 percent PAE. Finally, the TIM7785-16EL spans 7.7 to 8.5 GHz while... — Nancy Friedrich [Editor's Choice] Oscilloscope Characterizes Designs Beyond 40 Gb/s A wide-bandwidth oscilloscope is vowing to help engineers see the true performance of their designs on signals from 50 Mb/s to more than 40 Gb/s. The mainframe platform of the 86100D DCA-X permits engineers to make next-generation measurements that include integrated de-embedding capability. It scales from 2 ps/div to 1 s/div. The oscilloscope offers delays of 24 ns minimum with a maximum of 1000 screen diameters or 10 s (whichever is smaller). It provides time ... — Nancy Friedrich [RF Primer] EM Simulators Improve With Age Electromagnetic (EM) simulation has long been an essential modeling tool for RF /microwave design. Before selecting a simulator, however, it helps to understand the differences among EM solvers. On the simplest level, an EM simulator can be as basic as a cross-sectional analysis tool to derive parameters for a transmission line. For more complex structures, EM simulators can be differentiated by programs designed to analyze planar... — Jack Browne [Focus] System-In-Package Design Approach Promotes Portability — Diana Moncoqut [Focus] Lowpass Filters Span DC To 500 MHz — The Editors of Microwaves & RF [Focus] Thumb-Wheel Step Attenuator Spans DC To 18 GHz — The Editors of Microwaves & RF [Focus] Integration Paves Way For Compact PA Modules — Ashok Bindra [Focus] Connector Provides EMI Filtering With Hot-Shoe-Style Mating — The Editors of Microwaves & RF [Focus] Fast-Locking Connectors Shorten Assembly Time — The Editors of Microwaves & RF [Focus] Cable Assembly Cuts Loss To 0.90 dB/ft. At 40 GHz — The Editors of Microwaves & RF [Focus] 2.92-mm Connectors Offer Low VSWR Through 40 GHz — The Editors of Microwaves & RF [Microwaves in Europe] Rohde & Schwarz Enters Global Scope Arena Munich, Germany: Test and measurement specialist Rohde & Schwarz (R&S) chose the picturesque setting of Tegernsee in Southern Bavaria to announce its entry into the global oscilloscope market. Speaking at the event, R&S President and CEO Michael Vohrer said, “Our customers expect us to offer a complete line of products, and that includes oscilloscopes. To meet this demand, we are introducing a total of six new products of which we are extremely proud” (... — Paul Whytock |
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