Alternative to SMT for microwave and millimeter-wave systems
Jul 1, 2007
By Javed Siddiqui, Dan Sundberg and Dominick Suarez Conventional SMT works well for frequencies up to about 6 GHz. However, at higher frequencies SMT is usually not a viable option because in SMT topology the transmission lines are unshielded, and the components do not have adequate grounding. ...
Characterizing phase-locked loops with waveform scans
Jun 1, 2007
By Mike Hertz Identifying frequency stability problems within a phase-locked loop design can be greatly simplified when using an automated method. When an oscilloscope detects the period of a waveform cycle, this value can be directly inverted to compute the instantaneous frequency of the specific waveform cycle. ...
Applying a high linearity variable gain amplifier
May 1, 2007
By Tuan Nguyen The high linearity variable gain amplifier VG025 is designed for use in transmitter and receiver automatic gain-control circuits, and as variable gain blocks following low-noise amplifier stages in high dynamic range receiver front-ends....
Locating SSC errors using modulation profiles
Apr 1, 2007
By Mike Hertz Spread spectrum clocking allows for clocked devices to reduce radiated emissions by frequency-modulating the signal. This controlled modulation distributes the energy of the carrier across a wider frequency range, thereby reducing peak power....
RF wireless burst analysis using oscilloscopes
Feb 1, 2007
By Mike Hertz With real-time oscilloscope bandwidths now topping 18 GHz, capturing and analyzing the full band of ultrahigh-frequency RF signals is possible due to rapid performance advancements in real-time acquisition technology. ...
Successful LNA design involves performance trade-offs
Nov 1, 2006
By Thomas Baker While the low noise amplifier is a relatively simple design compared to other RF components in a cellular receiver lineup, the performance trade-offs it presents challenge the LNA application design engineer....
Bluetooth transceiver design using EDA software
Oct 1, 2006
By Emanuele Stavagna The RF portion of a transceiver designed by Dialog Seminconductor was designed using the EDA software package, Advanced Design System....
Optimizing mobile handset performance
Sep 1, 2006
By Greg Mendolia Making RF radios in mobile devices "tunable" is not a new development. But, tunable RF technology is seen as too lossy, too large, too expensive or having poor linearity....
Measuring high-speed signals with an active differential probe
Aug 1, 2006
By Ashok Bindra, editorial director For high-speed design and analysis, Tektronix recently introduced wide bandwidth DSA/DPO70000 oscilloscopes. To ensure signal integrity and accurate measurements when verifying, debugging and testing high-speed signals with these new-generation instruments, probes play a crucial role....
Low power, giga speed programmable divider in 0.18 m CMOS
Jul 1, 2006
By Girish N. Jadhav This article will focus on the design and simulation of a new programmable divider architecture for use in the 2.412 GHz to 2.484 GHz frequency bands....
Simulating PLL reference spurs
May 1, 2006
By Steve Williams and Tony Caviglia Spurious levels on the output of a phase-locked loop that generates a carrier signal are an important specification in many RF systems. Spurs may come from a variety of sources, but oneof the most common is the PLL's reference clock....
Micro-coax pigtails for RF measurements to and beyond 5 GHz
Feb 1, 2006
By Tracey Chavers One of the challenges faced by designers involved in contemporary radio design and debug is being able to accurately measure portions of a signal path that are not connectorized. The answer lies in careful use of pigtail micro-coxial cable....
High-performance active mixer overcomes RF transmitter design challenges
Jan 1, 2006
By James Wong A new generation of high-performance active mixers like LT5521 offers a combination of high linearity, low noise, easy LO drive, and with little or no conversion loss, resulting in a cost-effective, high-performance solution....
Push-pull amplifiers improve second-order intercept point
Nov 1, 2005
By Radhakrishna Setty Wideband communications systems have signals occupying multi-octave frequency ranges. Such signals, when amplified in conventional amplifiers, can be distorted due to the second-order products generated inside the amplifier. An ideal push-pull amplifier can cancel the internally generated products and preserve the signal quality. ...
AC parameters as they affect LDO performance in RF devices
Sep 1, 2005
By John McGinty Many AC parameters affect RF system performance including transient response, power supply ripple rejection and self noise. Power supply ripple rejection,...
Probing signals at 13 GHz
Jun 1, 2005
By Lon Hintze Lon Hintze previews the types of available probing solutions, the trade offs between them and the practical considerations for ensuring high signal fidelity and accurate measurements....
Increasing the speed of testing GSM/EDGE mobile phone power amplifiers
May 1, 2005
By Roland Minihold, Rohde & Schwarz Munich, Germany Testing is one of the critical operations necessary to ensure that GSM/EDGE mobile phones meet their required specifications. Consequently, reducing this...
