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ISSUE DATE: JUNE 2008 | |
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June 2008 - In This Issue [Cover Story] Fast Meters Scale Microwave Power Peaks Power measurements are critical for characterizing modern high-frequency systems and their components. With the growing use of pulsed and pseudorandom signals in both commercial communications and military radar systems, power meters capable of peak and continuous-wave (CW) measurements are more valuable than ever The new 4540 series of power meters from Boonton Electronics (www.boonton.com) is such an... — Jack Browne [News] RF/Microwave Technologies Advance For Military Systems Military electronics systems generally leverage the latest technologies in order to achieve performance or even tactical advantages. Although systems, such as radar and electronicwarfare (EW) platforms, are comprehensive collections of analog, digital, and RF circuits and devices, it is often the technology in a part as small as a transistor that can have an enormous impact on the overall performance of a military electronics system. For... — Jack Browne [News] Disparate Solutions Work To Fill Communications Gap More than seven years have passed since the Sept. 11, 2001 terrorist attacks. Since that time, the world has witnessed the subway bombings in the UK, the train bombings in Spain, and multiple other attacks. Government agencies have boosted their resources to gather more intelligence and prevent such attacks. In addition, they continue to emphasize the need for interoperable communications. Problems with communications continue to arise during... — Nancy Friedrich [Design Features] Coupled Stubs Support Microstrip Bandbass Filter Filters are essential in separating and sorting signals in communications systems. Filters are essentially two-port networks that can modify the frequency response of a communications system. In some applications, such as communications satellites and mobile communications devices, it is critical that filters be designed with small size and light weight. Planar filter geometries are well suited for meeting these requirements. The approach presented... — N. Nagachenchaiah , et al. [Design Features] Making Advanced Radar Measurements Evaluating the performance of an advanced radar system depends upon the capabilities of both the operator and the test equipment. The test gear must be properly specified to achieve accurate results for a number of key measurements, including rise time, frequency error estimation, and pulse-to-pulse phase measurements. Matching the capabilities of the test equipment to the expected performance of the radar system can ensure accurate and repeatable ... — Darren McCarthy [Design Features] Planar Resonators Arm Tunable Oscillators Communication systems rely on low-phase-noise signal sources such as tunable oscillators or phase-lock-loop (PLL) synthesizers for reliable voice communications and to ensure transmitted data integrity. Challenges still remain in achieving reasonable trade offs in low phase noise, low thermal drift, low power consumption, low cost, and potential for integration in integrated-circuit (IC) processes, however.1-38 With ever- increasing demands... — Ajay Kumar Poddar , et al. [Design Features] Multibeam Antenna Serves Broadband Wireless Coms Multibeam antennas can provide increased wireless communications capacity with enhanced spectral efficiency and higher quality of service. One approach to designing such an antenna involves the use of space division multiple access (SDMA) techniques. SDMA methods provide high user capacity in a limited frequency spectrum without any major technological changes.1 SDMA techniques, which are implemented by most wireless service... — Jasmin Desai , et al. [Product Technology] Cables And Connectors Deliver Robust Signals Cables and connectors are among the most overlooked components in any high-frequency system. Since they must deliver signals from one point to the next, without altering those signals, these transmission-line components are generally only noticed when they fail. In spite of the low profile, however, manufacturers continue to invest in these components in the quest of improved performance and reliability, to ensure that their cables and connectors ... — Jack Browne [Product Technology] Compact Oscilloscopes Check Embedded Systems Embedded systems, complete with memory, microcontrollers, and digital signal processing (DSP), can be found in the majority of modern electronic equipment, be it for commercial, industrial, or military applications. Checking the serial communications buses in these systems can be challenging without the right tools. Fortunately, the DPO3000 Digital Phosphor Oscilloscopes (DPOs) from Tektronix (... — Jack Browne [Product Technology] Microwave VNAs Add Nonlinear Network Analysis A dverse effects of nonlinear behavior in active and passive high-frequency components can disrupt communications systems. As a result, it is desirable to understand such behavior, which requires the right test equipment. To help, Agilent Technologies (www.agilent.com) has announced nonlinear vector network analyzer (NVNA) capability for its PNA-X series of microwave vector network analyzers (VNAs). ... — Jack Browne [Editorial] Students Abroad Also Spurn Science It is widely acknowledged that US engineering companies are attracting more international than homegrown talent. The problem is that less and less US-born students are going into engineering-related fields. In fact, they are less inclined to study mathematics and science in general. This issue has largely been blamed on our education system. When it was recognized decades ago that fewer students were continuing in math and science, many argued that there should have... — Nancy Friedrich [Feedback] Feedback How can metamaterials be viable for modulus of refractive index |n| < 1 when the curves indicate Vgroup =Vphase = –3c (speed of light)? This can be seen where: dn/d? = 0 for Vg = c[n–? (dn/d?)]–X where ? = wavelength in vacuum This also invalidates signal and energy velocity. We now have much literature with curves that correspond to the profoundly researched anomalous dispersion... — Various Readers [The Front End] Is Bluetooth And NFC A Marriage Made In Heaven? WELLINGBOROUGH, UK—For some time, the combination of Bluetooth technology and Near Field Communication (NFC) has been seen as the perfect match of short-range wireless technologies. Despite the talk, though, these technologies are by no means ready to drive off together into a golden sunset. Still, the view of the two technologies as complementary is well founded. According to IMS Research, Bluetooth already is well established in the market: More than half of the cellular... — Dawn Hightower [The Front End] Frost & Sullivan Honors AVX As Company Of The Year MYRTLE BEACH, SC—AVX Corp., a manufacturer of advanced electronic components and interconnect solutions, has received the 2008 Global Capacitor Company of the Year Award from Frost & Sullivan. That global consulting company empowers clients to create a growthfocused culture that generates, evaluates, and implements effective growth strategies. The Global Capacitor Company of the Year Award is based on many criteria including business development, competitive... — Dawn Hightower [The Front End] RFID Testbed Measures Multiple Tags At Once ATLANTA, GA—Researchers have designed a system that is capable of simultaneously measuring hundreds of radio-frequencyidentification (RFID) tags and rapidly testing new RFID-tag prototypes. According to Gregory Durgin, an assistant professor at the Georgia Institute of Technology’s School of Electrical and Computer Engineering, “This testbed allows us to measure the signal strength of tags hidden behind other tags and to rapidly test unique antenna and multiple... — Dawn Hightower [The Front End] Kudos MOSCOW, ID—Comtech AHA Corp., a wholly owned subsidiary of Comtech Telecommunications Corp., has surpassed the 20-year milestone as a provider of integrated circuits (ICs) and intellectual-property (IP) cores that implement forward-error-correction (FEC) technologies. The company was originally founded as Advanced Hardware Architectures (AHA) in 1988 based on error-correction technology developed by researchers at the University of Idaho for NASA. The founding... — Dawn Hightower [Financial News] Cobham Acquires M/A-COM For $425 Million THROUGH AN AGREEMENT WITH M/A-COM, Cobham plc will purchase M/A-COM’s radio-frequency components and subsystems business—one of the largest original-equipment manufacturers (OEMs) of microwave subsystems in the world—from Tyco Electronics for US $425 million in cash. That price will total an effective US $380 million after an allowable tax expense relating to good-will amortization. This transaction represents another step forward in Cobham’s growth... — Dawn Hightower [Company News] Company News CONTRACTS Hughes Network Systems, LLC—Signed an agreement with Globalstar, Inc. under which Hughes will design, manufacture, and implement the next-generation Radio Access Network (RAN) comprising gateway equipment at Globalstar’s worldwide locations with an option to expand to 30 locations. The company also will design, manufacture, and deliver satellite air-interface chips to be a part of the User Terminal... — Dawn Hightower [People] People Nitronex Names Sadler Principal Engineer DR. ROBERT A. SADLER has been named principal engineer for Nitronex. He has more than 27 years of industry experience in compound semiconductor device and process engineering. He most recently served as technical director, devices, for Northrop Grumman Corp., where he was responsible for the development of GaN technology. He also previously worked at RF Micro Devices as a principal scientist... — Dawn Hightower [Educational Meetings] Educational Meetings SHORT COURSES Besser Associates Short Courses Wireless Transceiver Design Techniques Aug. 11-15, 2008 (San Jose, CA) RF Transceiver Architecture, Design and Evaluation Nov.17-21, 2008 (Dallas, TX) Applied RF Techniques for Modern Radio Design Nov. 17-21, 2008 (Dallas, TX ) Wireless System Design and Simulation Dec. 8-12, 2008... — Dawn Hightower [R&D Roundup] Dielectric-Resonator Antenna Serves As Filter THE TREND TOWARD BUNDLING multiple components into a single module for wireless communications has researchers eying a dual-function DRA that can simultaneously act as the antenna and packaging cover. The problem is that the DRA’s quality (Q) factor tends to be low to enhance both radiation and bandwidth. In contrast, the Q-factor of the dielectric-resonator filter (DRF) is usually high to reduce insertion loss. It is therefore contradictory to... — Nancy Friedrich [R&D Roundup] Microwave Approach Detects Lymphatic Disease LYMPHATIC FILARIASIS (LF) is a parasitic infection spread by mosquitoes. This disabling and disfiguring disease is caused by thread-like parasitic worms. To accomplish the earlier detection of LF, a microwave method has been presented by Anil Lonappan, Vinu Thomas, G. Bindu, Joe Jacob, and K.T. Mathew from the Department of Electronics, Microwave Tomography, and Materials Research Laboratory at India’s Cochin University of Science and Technology... — Nancy Friedrich [R&D Roundup] Define Lightwave Antennas For Measurement Systems COMPARED TO MICROWAVE ANTENNAS, lightwave antennas have different measurement characteristics because of their use of shorter wavelengths. This aspect makes it difficult to design lightwave antennas according to each application system. A technique for measuring the far-field radiation pattern (FFP), gain, and transmissivity of each portion of an aperture has been described by Yasushi Munemasa, Tadashi Takano, and Makoto Mita from Tokyo University... — Nancy Friedrich [Application Notes] Wireless Medical Devices Eye Three Core Standards RECENTLY, INTEREST HAS GROWN in the potential of wireless technologies to enable a new generation of mobile personal-healthcare devices. These efforts are summarized in a white paper by EZURiO titled, “Wireless Connectivity – the Key to Enabling Personal Medical Technology.” The seven-page document explains that three wireless standards— Bluetooth, Wibree, and WiFi—will most likely dominate the majority of medical applications. Four primary parameters... — Nancy Friedrich [Application Notes] WiMAX and WiFi Make Strong Case For Users OVER TIME, WIMAX is expected to achieve similar attach rates to devices as WiFi. Yet it will not eclipse the usefulness of WiFi. In fact, service providers can bundle WiMAX and WiFi to deliver high-speed Internet connectivity in more places. In a joint paper from Intel and Motorola, the companies focus on the synergies between the IEEE 802.11a/g/n Orthogonal Frequency Division Multiplexing (OFDM) and IEEE 802.16e-2005 OFDM-Access (OFDMA) air interfaces. ... — Nancy Friedrich [Editor's Choice] Single-Chip MIMO Transceiver Covers 2.3 To 2.7 GHz TO MAKE IT EASIER to build in mobile-WiMAX support, a single-chip, 2.3-to-2.7-GHz, multiple-inputmultiple- output (MIMO) RF transceiver has emerged. By using a dual-receiver architecture to mitigate RF channel fading, the MAX2839 is vowing to improve receiver signal-to-noise ratio (SNR) by 10 dB compared to a single-receiver architecture. The transceiver’s two receivers feature a low noise figure at 2.3 dB and –81-dBm sensitivity for a ... — Nancy Friedrich [Editor's Choice] Pulse Modulators Switch In Under 500 ns A COMPACT LINE of magnetron pulse modulators has been spawned to replace tube-based pulsers for highpower- radar transmitters delivering peak RF powers of 3 to 50 kW. The DTI PowerMod solid-state pulse modulators provide over 99 percent switching efficiency. Depending upon load, pulse frequencies range up to 100 kHz. The modulators feature adjustable pulse widths from sub-microseconds to DC pulse to pulse. Under typical performance, the modules vow to... — Nancy Friedrich [Editor's Choice] Chip Resistors Are Optimized For 50-Ohm Impedance BY USING SPECIAL MANUFACTURING techniques to reduce voltage standing wave ratio (VSWR), a family of chip resistors has been optimized for 50-O characteristic impedance. Power ratings for the resistors range from 50 mW up to 200 W and a low return loss to 20 GHz. In addition to the standard and MIL-PRF-55342 case sizes, the new components are available in 14 standard case sizes: 0402 thru 3838. The resistors are available with single-surface or wrap-around terminations and a... — Nancy Friedrich [Editor's Choice] Cable Kit Checks WiFi And Broadband Infrastructure Cable Kit Checks WiFi And Broadband Infrastructure FOR BOTH WIFI and broadband infrastructure installation, cables are needed for RF and data throughput. With the variety of connectors available today and the popularity of reverse-polarity styles, it has become quite difficult to test these cable assemblies in the field. The RFA-4028-WIFI kit was created to simplify this task. The kit contains a Unidapt RF cable tester (RFA-4018-20) with an assortment of 30... — Nancy Friedrich [Bookmark] Microwave System Design Tools and EW Applications Electronic warfare (EW) system design involves both analog and digital electronics often operating across broad bandwidths, including millimeter- wave and optical frequencies. Design of the RF and microwave portions of these systems involves a strong understanding of how individual components perform and how they interact as part of analog signal-processing chains. Peter East’s Microwave System Design Tools and EW Applications provides an excellent introduction to... — Jack Browne |
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