ISSUE DATE: JULY 2009  OPTIONS
Amplifiers & Antennas

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July 2009 - In This Issue

[Cover Story]
VVAs Control Amplitude To 6 GHz
Voltage variable attenuators (VVAs) provide electronic control over signal levels, ideally with little or no distortion of the signals being controlled. In the case of the new VVA series of attenuators from Mini-Circuits, output waveforms are reduced in level with minimal distortion. The VVAs can provide level reductions as small as a few tenths of a decibel, or as large as typically 30 dB or more. The...  — Jack Browne

[News]
Transistors And Amplifiers Make Power Gains
Solid-state RF/microwave power was once limited to a few device options. But with everimproving semiconductor processes, transistors and transistor amplifiers are approaching output power levels that were once only possible with vacuum electron devices (VEDs), such as traveling wave tubes (TWTs). Devices and amplifiers based on silicon LDMOS and gallium nitride (GaN) are among the challengers to VED-based amplifiers. On the GaN front, ...  — Nancy Friedrich

[News]
Targeting EM Simulators Study Field Patterns
Increased reliance on electromagnetic (EM) simulation by high-frequency circuit designers was apparent by the number of EM simulator booths at the recent MTT-S Exhibition in Boston, MA. With the Sonnet Software (www.sonnetusa. com) booth visible from the entranceway, and through the scattered collection of EM simulation booths on the show flow, from dedicated shops like Zeland Software to full-service suppliers like ...  — Jack Browne

[Design Features]
TD-SCDMA Receiver Captures Multiple Channels
Wireless systems operators must adapt their networks to increasing data rates to meet customer demands. Next-generation wireless systems are adopting such techniques as receive diversity and multicarrier architectures to cope with the increasing data needs. In China, the use of time-division synchronous code-division-multiple-access (TD-SCDMA)1 as an alternative to wideband CDMA (WCDMA) attempts to provide improved coverage in a wide range of...  — Wei Hong , et al.

[Design Features]
Applying Practical TM Mode Propagation, Part 3
Earlier parts of this article (see May and June 2009 issues) described TM mode propagation on a single unconditioned conductor. The mode has many practical applications for last-mile information transport and distribution, for example by using the existing worldwide power grid, and can be applied as a lightweight transmission line for aerial antennas. An obvious and promising class of applications for this transmission mode involves employing...  — Glenn Elmore

[Design Features]
TWTs Still Drive High-Power Systems
Vacuum tubes were once the active devices of choice in high-frequency systems. With increasing use of solid-state devices, however, vacuum electron devices (VEDs) play less dominant roles in microwave and millimeter- wave systems, although they still offer the most power per device for most applications. Vacuum tubes such as klystrons, crossed-field amplifiers (CFAs), gyrotrons, magnetrons, inductive output tubes (IOTs) and, in particular, traveling wave...  — Meppalli Shandas

[Design Features]
Miniature Filter Screens VHF Band
Filters designed for lower frequencies such as VHF are usually large due to wavelength requirements. But a practical technique for achieving miniature microstrip filters at lower frequencies can yield designs for application over wide bandwidths. The technique has been demonstrated with a filter designed for use at 600 MHz, with simulated performance and measured results agreeing quite closely. The compact VHF filter design demonstrates good ...  — Deepankar Roy

[Product Technology]
Tracing Trends In RF Test Equipment
Demands on test equipment continue to increase as communications designers reach for more complex modulation formats. Several new instruments can be found in this issue, and some trends were apparent on the exhibition floor of the recent Microwave Theory & Techniques Society (MTT-S) event in Boston, MA: test-equipment specifiers want more power for their money and see low-cost solutions as Universal Serial Bus (USB) instruments to be...  — Jack Browne

[Product Technology]
Transceivers Power Pico Base Stations
Smartphones such as the Apple iPhone are driving demand for more broadband, datacentric technologies and the need for strategically positioned micro- and pico-sized cellular base stations. The AD9356 and AD9357 integrated transceivers from Analog Devices are each designed to provide two receive and transmit channels in a compact footprint while also reducing power consumption in broadband systems,...  — Chris Cloninger

[Product Technology]
Spectrum Analyzers Scour Signals To 14 GHz
Digital storage oscilloscopes (DSOs) with analog bandwidths to 4 GHz are powerful measurement tools for analysis and troubleshooting. But include built-in logic and protocol analyzers, and the three new Infiniium 9000 series DSOs from Agilent Technologies become mixed-signal oscilloscopes (MSOs) that can handle a wide range of test challenges, including troubleshooting equipment with high-speed PCIe...  — Jack Browne

[Editorial]
The Changing Ways Of RF Design
Designing circuits to match a transistor to 50 Ohms used to require sheets of paper preprinted with a Smith Chart, and then finding input and output matches. But design is “paperless” now, and the world has gone to using computer-aided-engineering (CAE) software not only for the matching networks but for anything else needed in a circuit or system. High-frequency designers rely on a variety of CAE tools, for linear and nonlinear circuits, electromagnetic ...  — Jack Browne

[Feedback]
Feedback
Software Important To Military Designers Dear Editor, Your story on military electronics in the June issue, “Targeting Trends In Military Electronics,” did a commendable job of covering a great deal of ground in a few pages. However, while addressing such areas as materials science and measurement equipment, it left out one important area to military system designers, and that is in the area of...  — Various Readers

[The Front End]
Bluetooth Low Power Technology Wins The Battle
WELLINGBOROUGH, UK— After a rigoroust 10 months, the decision regarind the chosen technologies for version 2 of Conitnua's design guidelines have been announced. Bluetooth Low Energy has been selected to enable low-powered portable medical devices in a personal-area-netowrk (PAN) setting. This usage includes portable devices, such as activity monitors and heart-rate sensors, which are used to monitor a user's health and fitness levels. For its part, ZigBee Health Care technology was...  — Dawn Hightower

[The Front End]
Alliances Preview Smart-Energy HAN Standard
The ZigBee and HomePlug Powerline Alliances have announced public availability of the next-generation market requirements for Smart Energy together with supporting use cases. Smart Energy enables wired and wireless communications between utility companies and everyday household devices, such as smart thermostats and appliances. The market-requirements document includes details about the next generation of functionality envisioned for the Smart Grid with accompanying...  — Dawn Hightower

[The Front End]
“Get Smart! Get Wireless!” Contest Winners Announced
DURING THE SPRING, Infineon Technologies, Microwaves & RF, and LS Research LLC had the opportunity to sponsor a design contest titled, “Get Smart! Get Wireless!” The objective of the contest was to simplify a wireless design using Infineon’s SmartLEWIS RX TDA5230 receiver. This receiver offers digital baseband signal processing to significantly reduce...  — Dawn Hightower

[Financial News]
CSR And SiRF Complete Merger
CSR plC and SiRF TeChnology holdingS, inC. (SiRF) have completed the merger between SiRF and a wholly owned subsidiary of CSR. Customers of the enlarged CSR group will be able to deliver new user experiences of connectivity and location technologies in a diverse range of devices, such as mobile phones, personal navigation devices, in-car navigation and telematics systems, laptop and netbook PCs, mobile Internet devices, digital cameras, gaming machines,...  — Dawn Hightower

[People]
Company News
CONTRACTS RF Engines Ltd. (RFEL)—Has been contracted by EONIC of Delft in The Netherlands for the development of a digital downconverter to be used in one of its latest signal-processing platforms. The high-speed design will enable the real-time extraction of large sections of spectrum from a wideband signal for subsequent analysis. The RFEL core will be implemented in a single Altera Stratix III field-programmable...  — Dawn Hightower

[People]
People
Padovani Receives 2009 IEEE Sumner Award ROBERTO PADOVANI, who developed and commercialized third-generation (3G) cellular communications networks incorporating code division multiple access (CDMA) technology, is being honored with the 2009 IEEE Eric. E. Sumner Award sponsored by Alcatel-Lucent Bell Labs. Since the mid-1990s, Padovani has been chiefly responsible for defining and pursuing the evolution of CDMA technology into the 3G standards...  — Dawn Hightower

[Educational Meetings]
Educational Meetings
MEETINGS 13th Annual Worldwide MASTERs Conference July 29-Aug. 1, 2009 (Phoenix, AZ) To register, go to: http://www.microchip.com/masters Conference cost is $1,295 and includes three-night accommodations with meals and evening entertainment For more information go to: ...  — Dawn Hightower

[R&D Roundup]
CMOS Schottky-Diode Doubler Extends To 140 GHz
Thanks To recenT cMos advances, it has become possible to implement voltage-controlled oscillators (VCOs) and a Schottky diode detector operating above 100 GHz. In fact, a millimeter-wave Schottky-diode frequency doubler fabricated in CMOS has been developed by Chuying Mao, Chakravartula Shashank Nallani, Swaminathan Sankaran, Eunyoung Seok, and Kenneth K. O from the University of Florida. The doubler, which is built in 130-nm CMOS, can generate signals to 140...  — Nancy Friedrich

[R&D Roundup]
Pentagon-Shaped Microstrip Antenna Serves UWB Applications
planar forMs of UlTra-wideband (UWB) antennas can be integrated between the radio-frequency (RF) front-end circuitry and the radiating structure. They can therefore be implemented using microstrip technology. At California’s San Diego State University, Sunil Kumar Rajgopal and Satish Kumar Sharma presented a UWB microstrip antenna that combines a pentagon-shaped slot, feed line, and pentagon stub to obtain a 124-percent impedance bandwidth from 2.65 to 11.30 GHz. ...  — Nancy Friedrich

[R&D Roundup]
60-GHz Amplifiers Leverage Commercial CMOS Process
UsUally, MilliMeTer-wave power and variablegain amplifiers are designed using an expensive and high-performance—yet not widely available— III-V-based semiconductor technology. Now, a methodology has been presented that allows a high level of integration within a lowcost, 60-GHz CMOS transceiver. This work was conducted by Tim LaRocca, Jenny Yi-Chun Liu, and Mau-Chung Frank Chang from the University of California in Los Angeles. Using a commercial, 90-nm...  — Nancy Friedrich

[Application Notes]
Amplifier Satisfies Demanding Infrastructure Applications
much debate exists about whether galliumnitride (GaN) devices can replace or even outperform devices based on other technologies, such as laterally diffused metal oxide semiconductor (LDMOS) devices. In an application note titled, “GaN For LDMOS Users,” Nitronex Corp. compares LDMOS against GaN for RF power-amplifier (PA) stages. The 15-page document evaluates equivalent outputpower devices to illustrate both the...  — Nancy Friedrich

[Application Notes]
LDMOS Users Can Easily Switch To GaN
Low-noise ampLifiers (Lnas) must achieve very low noise figures, good input and output return loss, high linearity, low current, wideband stability, and robust performance to meet the needs of modern infrastructure receiver applications. Examples of such applications include cellular/ third generation (3G), industrial scientific medical (ISM), and WiMAX/fourth generation (4G). To deliver such optimized performance with minimum tradeoffs, Skyworks recommends the ...  — Nancy Friedrich

[Editor's Choice]
Clock Oscillators Reduce EMI By As Much As –15 dBc
Two spread-spectrum clock oscillators, dubbed the SSOC5 and SSOC7, promise to provide an efficient and economic method of reducing system electromagnetic interference (EMI) at its source—the clock oscillator. The modulated output frequency of the SSOC5 and SSOC7 enables EMI to be reduced by as much as –15 dBc compared to fixed crystal oscillators. The spreadspectrum oscillators operate from a +3.3-VDC supply voltage. The CMOS clock generators produce a...  — Nancy Friedrich

[Editor's Choice]
MEMS Switch Guarantees 100 Million Operations
An RF microelectromechanical-systems (MEMS) switch boasts the high-frequency characteristics of electromechanical relays with a life expectancy that rivals solidstate relays. Driven by an electrostatic drive system, the 2SMES-01 is rated for 100 million operations at 0.5 mA and 0.5-VDC. It has been tested over 1 billion cycles. At 10 GHz, the 50- 2SMES-01 features 30 dB of isolation. It exhibits 1 dB insertion loss and 10 dB return loss. The switch consumes 10 µW. The relay...  — Nancy Friedrich

[Editor's Choice]
Wideband Power Dividers Offer 18 dB Isolation
With growth forecasted in the wireless-broadband market and WiMAX in particular, many firms are targeting this area for product development. An example is a series of WiMAX power dividers covering 0.8 to 6.0 GHz. The wideband power dividers feature 18 dB of isolation and SMA connectors on all ports. These Wilkinson designs use single or multistage layouts including two-way, four-way, and six-way configurations. Wilkinson power dividers are used in ...  — Nancy Friedrich

[Editor's Choice]
Synthesizer Covers 1 To 113 MHz
Synthesizer applications abound with the more typical ones including wireless communications, precision clock sources, and radar and surveillance systems. To meet the evolving needs of such systems, the ultra-low-noise LN310 synthesizer covers the 1-to-310-MHz band with a +3 to +13 dBm output. It boasts 0.1-Hz resolution and a frequency switching speed below 5 s (to within 0.1 radian at new frequency). The device offers amplitude switching below 50 s (to...  — Nancy Friedrich

[Focus]
Device Advances Lead To Lower LNA Noise Levels
 — Ashok Bindra

[Focus]
1-GHz TCXO Holds Jitter To Less Than 0.3 ps
 — The Editors of Microwaves & RF

[Focus]
Two-Stage LNAs Operate From 0.7 To 2.4 GHz
 — The Editors of Microwaves & RF

[Focus]
PA Pumps 10 W From 13.5 To 16 GHz
 — The Editors of Microwaves & RF

[Focus]
3.3-V LVCMOS Oscillators Extend Range To 200 MHz
 — The Editors of Microwaves & RF

[Focus]
Active-Load-Pull Measurement System Fully Characterizes PAs
 — The Editors of Microwaves & RF

[Focus]
Programmable TCXOs Run From 1.5 To 200 MHz
 — The Editors of Microwaves & RF

[Focus]
RF Adapters Gain Bandwidth While Lowering Return Loss
 — Ashok Bindra

[Focus]
Technology Integration Simplifies PCB/Cable-Harness Simulation
 — The Editors of Microwaves & RF

[Focus]
Float-Mount Design Translates Into Low VSWR
 — The Editors of Microwaves & RF

[Focus]
Lightweight Connector Keeps Water Out
 — The Editors of Microwaves & RF

[Focus]
Tiny Switch Connector Covers DC To 11 GHz
 — The Editors of Microwaves & RF

[Focus]
Corning Garners IEEE Corporate Innovation Honors
 — The Editors of Microwaves & RF

[Focus]
Wideband Passive Components Pose Measurement Challenges
 — Darren McCarthy

[Focus]
Mobile-Phone Antenna Functions In Full Metal Enclosure
 — The Editors of Microwaves & RF

[Focus]
300-MHz BPF Features 48-MHz 1-dB Bandwidth
 — The Editors of Microwaves & RF

[Focus]
Band-Reject Filters Can Be Tuned Over ±7.5-Percent Range
 — The Editors of Microwaves & RF

[Focus]
Coupler-Detector Covers 2.4 To 2.5 GHz Range
 — The Editors of Microwaves & RF

[Focus]
2-W Chip Resistors Flaunt Low Heat Rise
 — The Editors of Microwaves & RF

[Focus]
Radio-Channel Emulator Serves Multi-Antenna Mobile Test
 — The Editors of Microwaves & RF