ISSUE DATE: OCTOBER 2007   OPTIONS
Passive Components

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October 2007 - In This Issue

[Cover Story]
Digital VGAs Simplify And Shrink Wireless Transceivers
Signal amplification is a key function in high-frequency radios. Many newer wireless-communications systems rely on maintaining stable amplitude within the radio's downconversion circuitry even when faced with a wide range of input signal levels. Because of this, the variable gain amplifier (VGA) has become an essential building block in many wireless radio transceivers. Traditional VGAs have varied the DC voltage to set the amplifier's gain, although additional circuitry and ...  — Richard Houlihan

[News]
Passive Components Squeeze Into Tighter Spaces
"Do more with less" is the mantra in much of today's electronics industry. It applies to aspects ranging from the size of a company's engineering team to the number of components in a given design. Of course, it also applies to the components themselves. Every day, passive components are being produced with the goals of achieving higher performance and greater integration in smaller packages - and, of course, at highly competitive prices. With so many new and...  — Nancy Friedrich

[News]
Measuring Advances In RF/Microwave Test Equipment
Untitled Document Test-equipment manufacturers try to stay one or two steps ahead of the needs of their customers. To do this, they often listen to many customers and hope to anticipate their next ...  — Jack Browne

[Design Features]
Wireless Laboratory Aids Students And Research
Engineers have already played major roles in the development of wireless technologies and they will continue to do so. But engineers are made, and not born, requiring new integrative curricula at the undergraduate and graduate levels to foster the development of the next generation of wireless engineers. Part of this effort is already taking place at the University of South Florida, where a state-of-theart wireless-communications laboratory has been ...  — Huseyin Arslan

[Design Features]
Planar Filter Provide High Image Rejection
High-rejection filters are often useful in receivers and other systems where unwanted signal images must be removed without interfering with desired signals. By following a straightforward approach, it is possible to design planar filters for use at higher microwave frequencies. The technique relies on the positioning of transmission zeroes in order to selectively suppress the unwanted images. The approach also provides high suppression of spurious second-harmonic...  — Deepankar Roy , et al.

[Design Features]
Amplitude Equalizer Flattens Gain From 50 MHz To 7 GHz
High-speed communications links are increasing the demand for wider link bandwidths. While many commercial companies are now offering monolithicmicrowave- integrated-circuit (MMIC) Darlington amplifiers internally matched to 50 Ω and designed to operate over multiple decades of bandwidth, these amplifiers have their limitations in terms of performance. While they are small in size and low in cost, one potential disadvantage is the gain slope that...  — Martin Thornber

[Design Features]
Checking Communications Systems Interoperability
Communications systems provide reliable performance only after they have been tested under a wide range of operating conditions. Wirelesscommunications systems, for example, must be evaluated for the effects of such factors as path loss, immunity to interference, multipath reflections, and atmospheric losses. Real-world testing at the site of a communications system will yield the best overall information about the system, but this is not practical in most...  — Warren K. Gruber

[Design Features]
Design A Dual-Frequency Rectangular Patch Antenna
Patch antennas offer effective low-profile designs for a wide range of wireless applications. They are inexpensive to fabricate, light in weight, and can be made conformable with planar and nonplanar surfaces. The antennas are compact and compatible with microwave integrated circuits (MICs) for high-frequency applications. Unfortunately, they have some shortcomings, including relatively low gain, narrow bandwidth, and sensitivity to fabrication...  — Q. Lu , et al.

[Product Technology]
Tri-Company Teamwork Turns Out High-Frequency Oscillator
Companies within Dover Corp.'s Electronic Technologies have for years designed and manufactured RF/microwave products. But, as last month's first installment in this three-part article series pointed out, the RF/microwave companies are only now learning what is possible through teamwork. For three companies in particular, Dielectric Laboratories (www.dilabs.com), K&L Microwave (...  — Jack Browne

[Product Technology]
Supplier Transforms Switches Into Higher-Level Assemblies
Maximizing engineering resources is of utmost importance to most military-electronics contractors, to the point where many of the largest suppliers have turned to traditional RF/microwave component houses in search of subassembly integration. One of the long-running RF/microwave component suppliers that has learned how to blend its component business with its expanding subsystem integration skills is Daico Industries (...  — Jack Browne

[Product Technology]
Signal Analyzers Study Modulation To 26.5 GHz
Wireless-communications systems rely on advanced signal-modulation formats for efficient use of limited channel bandwidths. But as those modulation formats grow in complexity, they also increase the measurement challenges. Fortunately, Anritsu Co. (www.us.anritsu.com) has developed a trio of signal analyzers with the wide modulation bandwidths needed for wireless-communications testing. The models...  — Jack Browne

[Product Technology]
Handheld Spectrum Analyzer Scans 100 kHz To 3 GHz
Portable measurement capability serves a growing number of wireless and wireline communications applications. For site surveys, checking breaks in cables, or evaluating tower-mounted antennas and amplifiers, it is usually easier to bring an analyzer to the problem than the other way around. For that reason, Agilent Technologies (www.agilent.com) has developed the company's first portable, handheld...  — Jack Browne

[Editorial]
Combine Resources To Increase Reach
Oftentimes, an individual or a small company is better able to foresee an industry’s future needs than larger organizations. It also is small and agile enough to properly prepare to satisfy those needs. The electronicdesign- automation (EDA) industry, for example, has survived and flourished mostly because the bigger companies acquired and therefore expanded startups that were working on what would be needed next. In any industry, however, such acquisitions are often looked...  — Nancy Friedrich

[Feedback]
Breaking The Hatred Cycle
Please keep your pc mealy mouthed opinions out of your tech reviews. I’m speaking of the very last paragraph of the subject article (“Fighting The War Against IEDs,” Final Thoughts, Penton’s Military Electronics, September 2007). To say we need to “address social and cultural pressures” is ridiculous when speaking of Islamic terrorists trying to kill non- Muslims for hundreds of years. The attacks...  — John Evans

[The Front End]
iSuppli Reduces Its 2007 Semiconductor Forecast—But Sees Reasons For Optimism
EL SEGUNDO, CA—iSuppli Corp. has reduced its forecast of global semiconductor revenue growth in 2007 to 3.5 percent, down from its previous prediction of a 6-percent rise. Ironically, the downward revision comes at a time when chip revenue is up, the memory industry is improving, and the outlook for electronic-equipment markets is on the rise. However, these stronger conditions in the second half of 2007 will be insufficient to completely...  — Compiled by John Curley

[The Front End]
TriQuint Semiconductor Completes Acquisition Of Peak Devices, Inc.
HILLSBORO, OR—TriQuint Semiconductor, a manufacturer of wireless products, announced that it has completed the acquisition of Peak Devices, Inc. of Boulder, CO in a cash transaction introduced last month. Peak Devices is a privately held, fabless semiconductor company with an RF team that focuses on RF discrete transistor technology. Its market segments include two-way communications, FM and television broadcast, telecommunications, avionics, radar, and military. ...  — Compiled by John Curley

[The Front End]
SDR Forum Study Looks At Cognitive Radio
DENVER, CO—With the rapid emergence of cognitive radio (CR), this hot-button technology promises to achieve the vision of multimedia wireless services anywhere, anytime, and with any device, according to a study commissioned by the Software Defined Radio (SDR) Forum (www.sdrforum.org), a nonprofit international industry association for reconfigurable wireless technology. A cognitive radio intelligently ...  — Compiled by John Curley

[The Front End]
Kudos
OTTAWA, ON AND MONTREAL, QC, CANADA—Canada’s Telecommunications Hall of Fame announced that it will confer its Career Service Award on Dr. Gilles Y. Delisle, ing., P.Eng., a telecommunications engineer and educator who has devoted more than three decades to sharing his expertise with students in Quebec and eastern Ontario and the developing world. Dr. Delisle, currently vice president of research at the Montreal-based International Institute of...  — Compiled by John Curley

[Financial News]
Nokia Is To Acquire NAVTEQ
Nokia and NAVTEQ have announced a definitive agreement for Nokia to acquire NAVTEQ. Under the terms of the agreement, Nokia will pay $78 in cash for each share of NAVTEQ including outstanding options for an aggregate purchase price of approximately $8.1 billion (euro 5.7 billion), or approximately $7.7 billion (euro 5.4 billion) net of NAVTEQ existing cash balance. The acquisition has been approved by the board of directors of each company and is subject...  — Compiled by John Curley

[Company News]
Company News
Contracts ViaSat—Announced that it has secured a delivery order valued at $2.4 million for Multifunctional Information Distribution System (MIDS) terminals in support of the Republic of Korea (South Korea). The 24-month contract, beginning in May 2008, includes four LVT(11) ground-based Low Volume Terminals and associated support equipment. Agilent Technologies, Inc.—Announced that the US Navy has selected the...  — Compiled by John Curley

[People]
People
International Communications Group, Inc. (ICG)—Darrell Andregg to director of engineering; formerly director of firmware development at Axxcelera Broadband Wireless. Echolab Corp.—Tom Oriola to regional sales manager for the northern US and Canada; formerly sales engineer. Also, Mike Mitchell to regional sales manager for the Western US and Canada; formerly employed at VMI, Inc. iSuppli Corp.—David Carnevale to vice...  — Compiled by John Curley

[Educational Meetings]
Educational Meetings
Short Courses R.A. Wood Associates Short Courses Introductory RF and Microwaves November 5-6 (Philadelphia, PA) RF and Microwave Receiver Design November 7-9 (Philadelphia, PA) RF Power Amplifiers, Classes A-S: How the Circuits Operate, How to Design Them, and When to Use Each November 12-13 (Philadelphia, PA) For further information, contact: R.A. Wood Associates 1001 Broad...  — Compiled by John Curley

[R&D Roundup]
Negative-Resistance Cell Benefits Millimeter-Wave CMOS VCO
Many advanced communication and sensor systems include millimeter-wave voltage-controlled oscillators (VCOs) as key components. Recently, such devices have been realized in CMOS technology. Compared to III-V compound devices or silicon-germanium (SiGe) HBT, CMOS devices boast lower unit current-gain frequency and maximum oscillation frequency. It is therefore essential to investigate the highfrequency behavior of a negative-resistance cell when designing...  — Nancy Friedrich

[R&D Roundup]
UWB-IR Transmitter Dissipates 29.7 mW At 2.2-V Supply Voltage
In wireless-sensor newtork systems, many wireless terminals collect information like temperature and humidity. ZigBee has been billed as the optimal solution for such networks. Yet Ultra Wideband Impulse Radio (UWB-IR) may prove to be an even better solution. Such thinking led to the development of a UWB-IR transmitter with a digitally controlled pulse generator by Hitachi Ltd.’s Takayasu Norimatsu, Ryosuke Fujiwara, Masaru Kokubo, and Masayuki Miyazaki in...  — Nancy Friedrich

[R&D Roundup]
HTS Filters Undergo Mechanical Tuning
HTS filters are known for their low insertion loss and high out-of-band rejection. Yet the performance of these filters may be negatively impacted by the thickness of the HTS film, dielectric-constant variations, and more. Tuning work is therefore required to guarantee high performance in an HTS filter. Such tuning may be mechanical, electrical, or magnetic in its approach. At Tsinghua University in Beijing, China, researchers successfully used a mechanical tuning method to correct...  — Nancy Friedrich

[Application Notes]
DDS-Based Signal Sources Conquer Semiconductor Characterization
With so many modern products relying on semiconductors, it is essential that the behavior of these devices be accurately evaluated. By emulating the waveforms found in actual applications, signal sources promise to help engineers accurately evaluate the behavior of some basic semiconductor devices. In “Semiconductor Device Characterization Counts on Flexible Stimulus Signals,” Tektronix, Inc. (...  — Nancy Friedrich

[Application Notes]
Raise The Visibility Of Remote Microwave Sites
For network operators, support for analogmicrowave monitoring equipment is not always easy to attain. Yet many companies are still relying on microwave transport for their communications network sites. To help those operators improve site monitoring and maximize network visibility, DPS Telecom (www.dpstelecom.com) recently released a white paper titled, “Microwave Site Monitoring: A Guide to Achieving...  — Nancy Friedrich

[Editor's Choice]
RF Synthesizer Integrates VCOs For Operation To 5 GHz
Equipment manufactures have been increasingly demanding space and cost-efficient solutions for radio applications with frequencies in the microwave range. A single-chip RF synthesizer with integrated voltagecontrolled oscillators (VCOs) is planning to fulfill that need with operation up to 5 GHz. Dubbed the STW81103, it has measured phasenoise performance of 0.27 deg. root mean square (RMS) at 1.16 GHz, 0.6 deg. RMS at 2.33 GHz, and 1.5 deg. RMS at 4.67 GHz with a frequency step...  — Nancy Friedrich

[Editor's Choice]
Configurable Test Platform Operates To 6 GHz
The PXI Studio measurement system encompasses the PXI 3000 Series hardware modules, PXI Studio software with measurement plug-ins, and a PXI instrument chassis. The PXI 3000 Series modules now include the following: the 3025C, a 1-MHz-to-6-GHz digital signal generator; the 3030C, a 250-kHz-to-3-GHz wideband RF digitizer; and the 3035C, a 250-kHz-to-6-GHz wideband RF digitizer. These products extend the frequency-range coverage of the PXI 3000 Series hardware modules to include 250 kHz...  — Nancy Friedrich

[Editor's Choice]
Demodulator Flaunts PGA With 24 dB Of Gain Range
Compared tosuperheterodyne architectures, a monolithic, high-linearity quadrature demodulator is vowing to reduce the component count of the receive signal chain in third-generation (3G) base stations by at least 75 percent. The TRF3710 demodulator integrates a baseband filter that is software-programmable with 1-dB corner frequency. It can continuously cover signal bandwidths of 615 kHz (single-carrier CDMA2000) to 1.92 MHz (single WCDMA carrier). The device includes a...  — Nancy Friedrich

[Editor's Choice]
LNA Modules Promise Noise Down To 1.8 dB
Bridging applications ranging from broadband test equipment to aerospace and defense systems, a line of lownoise- amplifier (LNA) modules covers up to 18 GHz in bands. The NEL- 0618T620-5MH broadband LNA, for example, covers 6 to 18 GHz. It delivers at least +20 dBm output power at 1-dB compression, gain of 28 dB ±2 dB or better, and a noise figure of 4 dB. This LNA operates from a single +12- VDC supply. In addition, it draws 490 mA or less and is temperature...  — Nancy Friedrich

[Bookmark]
Fundamentals of Vector Network Analysis
Vector network analysis (VNA) is among the most essential of RF/microwave measurement approaches, and Rohde & Schwarz (www.rohdeschwarz. com) is among the world’s leading manufacturers of test equipment for this purpose. While the firm is associated with a wide range of high-performance test equipment, including spectrum analyzers, signal generators, and telecommunications test systems, few readers...  — Jack Browne