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ISSUE DATE: JULY 2007 | |
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July 2007 - In This Issue [Cover Story] Mirror Symmetry Makes High-Performance Hybrids Dimensional tolerances are critical to both electrical performance and manufacturing yield of high-frequency circuits. Since every deviation in a printed-circuit-board (PCB) trace represents a significant portion of a wavelength and RF and microwave frequencies, circuit patterns must be tightly controlled with minimal irregularities to achieve consistent electrical performance. This can be done with the highest-caliber PCB photolithographic techniques and... — Jack Browne [News] Software Eases Design Pain At Various Stages Every spring, people in the US microwave industry eagerly anticipate the major product announcements that will be unveiled at the IEEE Microwave Theory & Techniques Symposium (MTT-S) International Microwave Symposium (IMS). This year's show in Honolulu, Hawaii, did not disappoint them. As always, the exhibition floor teemed with the latest RF components, materials, and product innovations. In addition, test and measurement advances were highly visible. Yet the show ... — Nancy Friedrich [News] Waveguide Components Cut Losses While Passing Power Waveguide components are among those unique structures developed to pass microwave energy from one point in a system to another with minimal losses. Although restricted to specific bandwidths by the relationship of their dimensions to wavelength, waveguide transmission lines are still unparalleled in their low signal loss characteristics. Depending upon the construction materials, waveguide transmission lines, flanges, and components are also capable of handling higher RF power levels... — Jack Browne [Design Features] Understanding P2D Nonlinear Models Measurement-based nonlinear amplifier models ideally predict the performance of a high-frequency amplifier as accurately as possible. A usable nonlinear behavioral model can project the performance of a design under different operating conditions, saving the time and expense of building an amplifier circuit for experimentation. Of course, detailed circuit models often require a transistor model, a package model, and models for the transmission lines, passive elements,... — Dr. Lawrence P. Dunleavy , et al. [Design Features] Matching An ADC To A Transformer Analog signals are often digitized as quickly as possible in modern communications systems and test equipment in order to perform signal processing in the digital domain. But designing the transformer frontend circuitry for an analog-to-digital converter (ADC) can be challenging, especially in systems with high intermediate frequencies (IFs). Fortunately, this streamlined, five-step process can help develop an optimum front end for an ADC. It can be applied easily and quickly to... — Rob Reeder [Design Features] Predict Resonances Of Shielded PCBs Microwave circuits are generally enclosed in rectangular shields before integration into a larger system. Unfortunately, when the shield cover goes on, it can cause unexpected results, such as the oscillation of "unconditionally stable" amplifiers, an increase in transmission-line losses, and unwanted coupling. Essentially, the presence of the shielded enclosure can throw off all those advanced computer-aided-engineering (CAE) predictions. And, because it is late in the design... — Avinash Sharma [Design Features] Sliced Coaxial Cables Form Compact Couplers Coupled sliced coaxial cables can provide signal coupling in a compact form factor for 50and 75-W systems. With the ready availability of accurate computer-aided-engineering (CAE) tools, it is possible to apply some basic formulas for calculating the dimensions of these structures to achieve a desired amount of coupling on different substrate materials. What follows is a straightforward approach to calculating those dimensions and analyzing coupler designs fabricated with coupled... — Nasreddine Ben Ahmed , et al. [Product Technology] LDMOS FETs Reach 1-kW Peak Output Power Solid-state RF power for industrial-scientific-medical (ISM) applications usually requires multiple transistors to reach levels of 1 kW and more. Magnetic-resonance-imaging (MRI) systems, for example, employ power amplifiers that can deliver in excess of 20 kW of peak RF power. To serve these applications, Freescale Semiconductor (Tempe, AZ) has introduced the MRF6VP11KH, which delivers RF output power of 1 kW at 130 MHz—currently the highest-power commercially... — Pierre Piel [Product Technology] Spread-Spectrum Module Fits 3.4-GHz Military Radios Secure communications is critical in battleplace as well as in public-safety and other government-agency applications. Frequency-hopping spread-spectrum techniques can ensure voice and data security over long-range communications links, and such technology is now with-in range of most radio system manufacturers with the introduction of the model 3400 SMR board-level spread-spectrum radios from FreeWave Technologies (Boulder, CO). Designed for use from 3.3 to 3.5 GHz, ... — Jack Browne [Editorial] Hawaii Gets A Thumbs Up After All When the Honolulu, Hawaii location for this year's Microwave Theory and Techniques Symposium (MTT-S) was revealed some years ago, people reacted with both anticipation and disbelief. Among the folks with whom I spoke, there seemed to generally be a positive, excitement-filled reaction. As 2007 got closer, however, some companies vowed that they would not exhibit if the society stuck to the Hawaii location. In addition, rumors were widely circulated that the location had... — Nancy Friedrich [Feedback] PTS Synthesizers MICHAEL LOHRER is right on the money about Programmed Test Sources and their synthesizers ("Survey Omission," Feedback, May 2007, p. 13). We love them here at CEC and use them as essential components of many of our transmitters. They're about the most reliable units we've seen over the years. And we've never had a case where a PTS unit didn't live up to its specifications. The phase noise is always within specifications as is the accuracy. Another great thing about ... — J. Fred Riley, JD, MBA [Feedback] Antenna Report Just a short word regarding your news report ("Antennas Set Patterns For Wireless Growth," p. 48) in the May 2007 issue of Microwaves & RF. "So the antenna, so the radio station" was an old saying that proves still worthy applying. Ghislain... — Ghislain Ruy [The Front End] iSuppli Predicts 6-Percent Semiconductor Revenue Growth In 2007 EL SEGUNDO, CA—While many researchers are cutting their forecasts for 2007 semiconductor revenue growth to the 2-percent range, iSuppli Corp. (www.isuppli.com) predicts a healthy 6-percent increase this year. Global semiconductor revenue will rise to $276.6 billion in 2007, up from $260.9 billion in 2006. iSuppli's previous forecast, issued in April, predicted an 8.1-percent increase for the year. The ... — Compiled by John Curley [The Front End] Wireless Sensor Networking Enables Next-Generation Parking Solutions ROSEMONT, IL—Dust Networks™, a provider of low-power wireless sensor networking (WSN) systems and Streetline, Inc. announced that Dust Networks has been selected as the WSN provider for Streetline's City Infrastructure Technologies (CiT) Platform. Dust's network-ready SmartMesh® products, based on the company's Time Synchronized Mesh Protocol (TSMP™), are integrated into Streetline's parking-management solutions—including... — Compiled by John Curley [The Front End] QUALCOMM And MLB Announce BREW Agreement SAN DIEGO, CA—QUALCOMM, Inc., a developer of wireless technologies and mobile data solutions, and MLB Advanced Media, LP (MLBAM), the interactive media and Internet company of Major League Baseball, have announced an agreement to leverage QUALCOMM's BREW®BrandXtend Signature Solution customer and will use it to offer baseball fans new access channels for the discovery and delivery of compelling mobile content offered exclusively by MLB.com. The solution... — Compiled by John Curley [The Front End] Kudos PITTSBURGH, PA—BusinessWeek ranked Ansoft Corp. 25th on its annual Hot Growth list of America's 100 fastest-growing small companies, improving upon last year's ranking of 46. After analyzing data from 10,000 pubic companies with revenues of $50 million to $1.5 billion a year, BusinessWeek selected the top 100 finalists whose sales, earnings, and return on capital grew the fastest over three years. CHERRY HILL, NJ—inTEST Corp.... — Compiled by John Curley [Financial News] ATC Agrees To Be Acquired By AVX American Technical Ceramics Corp. (ATC), a manufacturer of electronic components, including capacitors and thin-film circuits for a range of commercial and military applications, announced that it has signed a definitive merger agreement with AVX Corp. pursuant to which all of the outstanding equity interests of ATC will be acquired by AVX. Pursuant to the merger, each outstanding share of ATC common stock will be converted into the right to receive $24.75 in... — Compiled by John Curley [Company News] Company News CONTRACTS Harris Corp.—Has been awarded an Indefinite Delivery, Indefinite Quantity (IDIQ) contract with a potential value of up to $2.7 billion to supply the US Department of Defense with its next-generation multiband Falcon III handheld tactical radio systems. The contract includes additional options that, if exercised over a five-year period, could increase the potential value to nearly $7 billion. Harris... — Compiled by John Curley [People] People iSLI Names Michael Kay As New Chairman The Board at iSLI, Institute for System Level Integration, announced that MICHAEL KAY has accepted the role of chairman. Previously, Kay founded and was managing director of the Motorola Technology Centre in Scotland. See Associated Figure PCTEL—BOB SUASTEGUI to vice president and general manager of global sales and marketing;... — Compiled by John Curley [Educational Meetings] Educational Meetings SHORT COURSES R.A. Wood Associates Short Courses Introductory RF and Microwaves September 10-11 (Syracuse, NY) November 5-6 (Philadelphia, PA) RF and Microwave Receiver Design September 12-14 (Syracuse, NY) November 7-9 (Philadelphia, PA) RF Power Amplifiers, Classes A-S: How the Circuits Operate, How to Design Them, and When to Use Each September 17-18... — Compiled by John Curley [R&D Roundup] UWB LNA Achieves Maximum Gain Of 13.5 dB From 1.85 To 10.2 GHz Many researchers are evaluating Ultra Wideband's (UWB's) applicability for short-range, high-speed wireless communications. Yet these systems must first overcome a challenging building block: the low-noise amplifier (LNA). A UWB LNA was recently proposed by Jihak Jung, Taeyeoul Yun, and Jaehoon Choi from Hanyang University in Seoul, Korea in conjunction with Hoontae Kim from the Samsung Advanced Institute of Technology. This CMOS LNA has a common-source feedback... — Nancy Friedrich [R&D Roundup] Microwaves Determine Pregnancy Through Urine Analysis Shortly after conception, the human chorionic gonadotropin (hCG) glycoprotein hormone is secreted by the developing placenta. During early gestational growth, hCG rises in concentration. As a result, hCH is an excellent marker for the early detection of pregnancy. When the dielectrical properties of pregnant versus non-pregnant women are analyzed at microwave frequencies, the results indicate that the dielectric constant of the pregnant women's urine samples is smaller... — Nancy Friedrich [R&D Roundup] Microstrip Patch Antenna Populates CPW Stub With MEMS Capacitors Using radio-frequency microelectromechanical-systems (MEMS) technology, a tunable frequency microstrip patch antenna has been developed. It consists of a patch antenna loaded with a coplanar-waveguide (CPW) loading section, which is attached to the antenna via a microstrip-to-CW transition. To provide reconfigurability in the antenna's resonant frequency, MEMS bridges act as a variable capacitor placed on the CPW stub. The MEMS capacitors are electrostatically actuated... — Nancy Friedrich [Application Notes] RF Immunity Testing Helps To Maintain Quality Performance Unwanted signals are proliferating in part because of the popularity of GSM cell phones. Such RF signals can disrupt the operation of electronic circuits without adequate RF noise-rejection capabilities. To guarantee the satisfactory operation of electronic circuits in the presence of RF interference, RF-immunity testing has become critical. MAXIM (Sunnyvale, CA) examines this topic in a white paper titled, "A Measurement Technique for Determining RF... — Nancy Friedrich [Application Notes] VNA Options Enhance Amplifier Measurements Characterizing a high-frequency amplifier can be rather tricky. In fact, just configuring a network analyzer for the right set of measurements can be challenging. To ease this process, Rohde & Schwarz (Hants, United Kingdom) offers a 17page-long application note titled, "Performing Amplifier Measurements with the Vector Network Analyzer ZVB." The note, which is based on the firm's model ZVB instrument, begins by illustrating the basic analyzer configuration for... — Nancy Friedrich [Editor's Choice] Vector And Spectrum Analyzers Merge To perform their jobs, RF engineers often rely on both spectrum analyzers and vector network analyzers (VNAs). To make it easier for designers to leverage these instruments, the ZVL series merges a full-featured VNA with a spectrum analyzer in one portable instrument. The ZVL is available in frequency ranges from 9 kHz to either 3 or 6 GHz. It flaunts dynamic range of 123 dB, bidirectional measurement capability, analysis functions like multi-trace display, and... — Nancy Friedrich [Editor's Choice] WiMAX Circulators Manage 0.20 dB Insertion Loss WIMAX is on the rise with networks set to deploy in cities across the globe. To support this buildup, a family of single-junction surface-mount circulators is well suited for various WiMAX applications. The MAFR-000229000001, MAFR-000050-5S4C1T, MAFR-000159-5S4C1T, and MAFR000200-5S4C1T circulators split the WiMAX frequency bands. The family boasts typical performance of 0.20 dB insertion loss with 25 dB of isolation. Each part has intermodulation distortion (IMD) of... — Nancy Friedrich [Editor's Choice] Portable Handheld Analyzers Span 2 To 1600 MHz Interoperability continues to be a problem for homeland-security, public-safety, and other agencies. To assuage this problem, the S311D/S312D Site Master cable and antenna analyzers combine a frequency of 2 to 1600 MHz in a portable, rugged design that weighs less than 5 lbs. The analyzers were developed to test the RF performance of P25 and TETRA systems in the very-high-frequency (VHF)/ultra-high-frequency (UHF), 400-MHz, and 700-to800-MHz bands. The S311D/S312D can... — Nancy Friedrich [Editor's Choice] X-Band GaN HEMT Boasts 50 W Output Power Many RF manufacturers are turning to galliumnitride (GaN) for its promise of higher power. GaN high-electron-mobility-transistor (HEMT) amplifiers, for example, may be capable of attaining significantly higher gain and output power than GaAs FETs at comparable frequency. The TGI8596-50 is an internally matched, GaN HEMT power amplifier. It operates in the 8.5-to-9.6-GHz range with output power of 50 W. Typically, this X-band device features a 3-dB compression point ... — Nancy Friedrich |
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