ISSUE DATE: APRIL 2009  OPTIONS
Communications

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April 2009 - In This Issue

[Cover Story]
VCOs Tune Miniature Synthesizers To 12 GHz
Miniaturization of voltage-controlled oscillators (VCOs) at lower microwave frequencies has long been limited by the size of the resonator. For the popular 4-to-8-GHz band, however, Synergy Microwave Corp. (Paterson, NJ) has managed to shrink multi-octave VCOs in that frequency range to a mere 0.3 x 0.3 in., with a companion line of frequency synthesizers that measure just 0.6 x 0.6 in. The discrete-device VCOs feature patented technology that achieves the high-stability...  — Ulrich L. Rohde , et al.

[News]
Cables And Connectors Link To New Applications
In an ever-changing world, the cable market is a place where a company’s expertise in one area can easily extend over decades. For example, W.L. Gore & Associates has been able to leverage its original work in polytetrafluoroethylene (PTFE) far beyond electronics. Think how many “new” cable assemblies are built with tried-and-true cable from firms like ...  — Nancy Friedrich

[Design Features]
UNB Modulation Salvages Spectrum
Spectrum is limited, but innovative communications formats using ultranarrowband (UNB) modulation may provide relief for added wireless services. UNB modulation formats have their limitations, of course, and it is important to understand the performance capabilities of UNB modulation and how systems can differ by their use of abrupt versus gradual changes in phase. In order to better understand UNB modulation, the relationship between phase...  — Shikai Zhang

[Design Features]
Evaluating Impedance Transformers With A VNA
Impedance transformers are widely used in radio communications applications to match the impedance of different devices and components to the 50- characteristic impedance of a high-frequency system. To evaluate the performance of an impedance transformer, a microwave vector network analyzer (VNA) can be used in such a way that measurement errors are minimized. Calibration procedures will be...  — Antonio Alves Ferreira, Jr. , et al.

[Design Features]
Analyzing A 5.5-GHz DRO For WLANs
Dielectric-resonator oscillators (DROs) provide low-noise signals for a variety of wireless and other applications. Computer- aided-engineering (CAE) tools can be invaluable in designing and optimizing the performance of these oscillators, as will be shown with the design for a prototype oscillator in support of wireless-localarea- network (WLAN) applications at 5.5 GHz. By applying a number of different CAE tools, including a harmonic-balance simulator...  — R.A. Abd-Alhameed , et al.

[Design Features]
Analyze Bearing Accuracy Of A Monopulse System (Part 2)
As detailed last month in Part 1 of this two-part article series, an amplitude monopulse system requires tightly matched amplitude balance between receiver channels to provide good bearing accuracy. Also, minimizing bearing errors depends on minimizing phase and amplitude imbalance in the SBFN and antenna. Differences in insertion loss and gain among these channels result from variations in physical components. The receiver channels also operate ...  — Leo G. Maloratsky

[Product Technology]
EM And Math Software Aids RF/Microwave Design
Software plays an increasingly important role in high-frequency design, especially as more functions are integrated into smaller circuits. Design engineers have a wide choice of computer-aided- engineering (CAE) software tools at their disposal, from full-featured, multi-program suites to single-function utilities. Two of the more versatile types of tools, mathematical and electromagnetic (EM) programs, help analyze a wide range of designs, from...  — Jack Browne

[Product Technology]
Converter/Exciter Fires EW And ECM Waveforms
Electronic warfare (EW), electronic countermeasures (ECM), secure communications, and electronic intelligence systems have the daunting challenge of detecting, characterizing, and countering threats with a diverse combination of characteristics over a wide frequency range. To accomplish this, they must be able to generate signals with precisely defined attributes at the frequency of the threat and do so at high speed. ...  — Jason Seifert

[Product Technology]
Power Amplifier Tackles WiMAX
Digital modulation formats place great demands on a communications system’s transmit power amplifier. Systems such as WiMAX and LTE employ signals with high peak-to-average (PAR) power ratios, requiring power amplifiers with low error-vector magnitude (EVM) and good linearity. Fortunately, Micro- Precision Technologies, Inc. has leveraged gallium nitride (GaN) device technology into a line of...  — Paul Pedigo

[Product Technology]
Radio Monitors Pipeline Integrity
Pipelines for water, oil, and natural gas can run for long distances, across areas difficult to check for leaks and damage. But the new IM-CP cathodic protection (CP) radio from FreeWave Technologies operates at 2.4 GHz for automated pipeline integrity monitoring over long distances, including in places difficult to access by physical means. The frequencyhopping, spread-spectrum, boardlevel radio...  — Jack Browne

[Editorial]
Customer Service Extends To The Web
Microwave companies are part of a small, closeknit community. Relationships with customers are strong and many customers know about new products before they are formally announced. Many companies are so familiar with their customers’ requirements that they can match new products to those needs. Such closeness lends much charm to this industry. But it also has led to some bad habits concerning customer service. Many companies fail to realize that their web sites are...  — Nancy Friedrich

[Feedback]
Feedback
White Papers Found Here In the January and February Application Notes, we spotlighted two white papers from Anatech that some people have had trouble locating on the company’s web site (see “Filter Choices Help To Eliminate Interference,” January 2009, p. 86 and “Specify Filters Right The First Time,” February 2009, p. 88). The white papers were meant to simplify the search process for RF/ microwave filters by...  — Various Readers

[The Front End]
Bluetooth Low-Energy Could Show Explosive Growth Rate In RF Remotes
OSLO, NORWAY—According to an ABI Research study, the RF remote-control sector—predicted to grow at a 55 percent annual growth rate between now and 2014—is ripe for transformation as decades-old infrared technology (IR) is phased out by radio-frequency technology. This forecast is supported by the Bluetooth SIG’s announcement that in addition to being power and cost optimized for the sport, well-being, and...  — Dawn Hightower

[The Front End]
Nordic Semiconductor Sponsors Bluetooth Innovation World Cup
OLSO, NORWAY - Nordic Semiconductor is sponsoring the Bluetooth Innovation World Cup—a Bluetooth Special Interest Group (SIG) competition targeting fitness, healthcare, and sports products. The competition will promote the rollout of Bluetooth low-energy wireless technology later this year. In conjunction with the Bluetooth SIG—an 11,000-memberstrong organization driving the development of Bluetooth wireless-the Bluetooth Innovation World Cup is being sponsored by...  — Dawn Hightower

[The Front End]
Nokia Pulls Billions In Business From Contract Manufacturers
EL SEGUNDO, CA—Nokia has announced that it has stopped using outside contract manufacturers for the assembly of its phones. The company cited weak global demand for mobile devices as the reason that it will cease employing outsourced production to electronics-manufacturing-service (EMS) providers and original design manufacturers (ODMs). Recently, Nokia had begun the process of shifting some of its assembly operations away from contract...  — Dawn Hightower

[Financial News]
FreeWave Founders Share Financial Success
FREEWAVE TECHNOLOGIES HAS distributed the third installment of a $9-million equity bonus to its employees. The bonus is part of a $113-million private-equity transaction. It was given by the company founders, CEO Steve Wulchin and CTO Jonathan Sawyer, to reward employees for the hard work and dedication that has helped Free- Wave become a leading supplier of high-performance spread-spectrum and licensed radio products and services. According to...  — Dawn Hightower

[Company News]
Company News
CONTRACTS Raytheon Company—Has been awarded a $23.9-million phase 3 contract from the Defense Advanced Research Projects Agency (DARPA) to continue work on the 38-month phase of the Wide Bandgap Semiconductor (WBGS) development program. The program is a collaboration between DARPA and the Missile Defense Agency (MDA). Their objective is to rapidly mature and demonstrate the capabilities of gallium nitride (GaN) to...  — Dawn Hightower

[People]
People
Gilbert Elected To US National Academy Of Engineering BARRIE GILBERT, a Technology Fellow with Analog Devices, Inc., has been elected to the US National Academy of Engineering (NAE). Gilbert, who directs engineering at the Northwest Labs in Beaverton, OR, is being honored by the NAE for his contributions to the field of analog circuit design. The Gilbert cell, a versatile...  — Dawn Hightower

[People]
Custom Synthesizers Span 167 To 6010 MHz
Frequency synthesizers generate stable RF/microwave signals for a variety of applications, from commercial communications to military systems. Standard models are available from a number of suppliers, but some jobs call for a special set of requirements. When a set of custom frequency synthesizer specifications must be met, Mini-Circuits offers an array of choices from fixed-frequency and narrowband units to broadband designs from 167 to 6010 MHz. ...  — Jack Browne

[Educational Meetings]
Educational Meetings
Meetings ARMMS RF & Microwave Society Conference April 20-21, 2009 (Oxfordshire, England) Milton Hill House For more information, visit: www.armms.org 2009 Global Symposium on Millimeter Waves (GSMM2009) April 20-22, 2009 (Japan) Sakura Hall, Tohoku Univerity, Katahira, Sendai, Japan ...  — Dawn Hightower

[R&D Roundup]
Power-Detection System Covers UWB Spectrum
Many wireless coMMunications systems must be able to measure received signal strength. To provide sufficient bandwidth to cover the Ultra Wideband (UWB) spectrum, a pair of researchers has expanded on the capabilities of a previously introduced system comprising an integrated CMOS broadband detector that uses the nonlinear behavior of a CMOS transistor in deep triode mode. The detector is now incorporated into a feedback loop for gain and filter control of an...  — Nancy Friedrich

[R&D Roundup]
Implanted Antenna Improves In-Body Communications
In short-range Biotelemetry applications, antennas are implanted inside the body to forge communication links between medical sensors and exterior instruments. Ultra Wideband (UWB) signal transmission from an in-body implanted antenna to on-body or outside-body devices for biomedical applications has been considered by Ali Khaleghi from Rikshospitalet University Hospital (Oslo, Norway) and Ilangko Balasingham from Norway’s University of Science and Technology. ...  — Nancy Friedrich

[R&D Roundup]
60-GHz Bandpass Filter Leverages Standard CMOS Process
With the increasing deMand for broadband multimedia applications, the 60-GHz band has garnered attention for short-range communications. Development has focused on on-chip antennas and filters integrated with low-cost, 60-GHz, integrated-CMOS RF front-end circuitry. At Taiwan’s National Cheng Kung University and National University of Tainan, a 60-GHz millimeter-wave on-chip bandpass filter has been designed and implemented using a 0.18-µm standard CMOS process....  — Nancy Friedrich

[Application Notes]
Software Analyzes Communications Systems
Because circuits do not Behave predictably at microwave frequencies, engineers must often tweak them to achieve better performance. Highfrequency circuit design tools have reduced the need for tweaking prototype circuits. Yet software tools for system-level analysis have not evolved as quickly, forcing designers to use spreadsheets to accomplish this task. As a result, engineers cannot account for the effects that will impact the system once it is deployed in the...  — Nancy Friedrich

[Application Notes]
Choose The Right Prescalers For PLL Synthesizers
Prescalers act as Frequency dividers in radio- and microwave-frequency translation and signal generation. Often, they are employed in phase-locked loops (PLLs) and frequency synthesizers to match the frequency of a high-frequency source to the frequency of a reference oscillator. With knowledge of how to bias and operate prescalers, engineers can design them into a wide range of high-frequency applications. In the six-page product application note titled,...  — Nancy Friedrich

[Editor's Choice]
ZigBee Module Scales Data Rates From 250 kb/s To 1 Mb/s
Low-power ZigBee technoLogy can be used for applications like home and building automation, industrial control, and medical patient monitoring. whereas most ZigBee modules run at 250 kb/s, the new Meshconnect ZigBee (ieee 802.15.4) modules run at 250 kb/s, 500 kb/s, or a full 1 Mb/s. As a result, they enable higher-speed applications as well as those that require burst throughput. there are two modules based on the Zic2410: the ZicM2410p0 with +6 dBm...  — Nancy Friedrich

[Editor's Choice]
Spectrum Analyzers Cover 1 kHz To 26.6 GHz
Four spectruM AnALyZers make up the new 3250 series. each one measures a frequency range beginning at 1 khz with the 3251 ranging to 3 ghz, the 3252 to 8 ghz, the 3253 to 13.2 ghz, and the 3254 to 26.5 ghz. the spectrum analyzers display local-oscillator (Lo) phase noise of –115 dBc/hz and a display average noise level (dAnL) of –145 dBm/hz. they incorporate 30 Mhz intermodulation/quadrature (i/Q) demodulation bandwidth and a removable hard disk. An optional built-in...  — Nancy Friedrich

[Editor's Choice]
L-Band VCO Operates At 1560 MHz
A VoLtAge-controLLed osciLLAtor (Vco) has debuted for fixed wireless and test and measurement applications that require superior second-harmonic suppression and low-phase-noise performance. the model Zro1560A1LF operates in L-band at 1560 Mhz with a tuning voltage range of 0 to 5 Vdc. this Vco features typical phase noise of –121 dBc/hz at 10 khz offset and a typical tuning sensitivity of 0.7 Mhz/V. the Zro1560A1LF typically delivers output power of 0 dBm at a +5-Vdc...  — Nancy Friedrich

[RF Primer]
Screening Requirements For Microwave Filters
Filters perform a simple function in RF/microwave designs: to modify in a controlled manner a signal applied at its input. That function may be defined as passing signals in the middle of a band and rejecting all other signals (bandpass filter), attenuating a small portion of a bandwidth (band-reject filter), passing signals at the bottom of the band and rejecting other signals (lowpass filter), or passing signals at the high end of a band and...  — Jack Browne