Semiconductors / Integrated Circuits

A Voltage-controlled PIN Diode Attenuator Using an Accurate PIN Diode Model

This article presents a voltage-controlled PIN diode attenuator using an accurate PIN diode model that can precisely simulate the attenuation characteristics. After carefully investigating the problems with conventional PIN diode models, an accurate PI...
PIN diodes have been widely used in a variety of microwave and RF applications, including antenna switches, phase shifters and attenuators. PIN diode attenuators are used extensively in automatic gain control (AGC) and RF leveling applications. Most PIN diode attenuators control the attenuation characteristics through the forward bias current....
Read More

Enterprise Software for RF Device Characterization

In today's competitive marketplace the characterization of RF semiconductor devices for modeling, design, applications and process improvement must be faster, more efficient, and more repeatable and accurate as companies strive to improve their product performance, design productivity and time to market. However, help is on hand with the Wavevue...
Read More

Ultra Linear Bandpass Filters

A new product line of ultra linear bandpass filters has been introduced that utilize patent pending cross coupling to reduce time delay and phase distortion up to 90 percent. The filters typically utilize a 12-section filter with two inductive and two capacitive non-adjacent couplings to equalize and flatten the...
Read More

2003 Connector, Cable and Cable Assembly Survey

This is the first survey of connectors, cables and cable assemblies sponsored by Microwave Journal. We hope to update it annually with increased industry participation.
On December 13, 2002, we sent a questionnaire to 75 companies that provide products and services in this field, with a response deadline of January 11th. We used e-mail rather than the USPS so that we would have feedback that all the questionnaires were received. On January 3, 2003,...
Read More

Precision Test Cable Assemblies to 40 GHz

The Accu-Test™ products are a family of precision cable assemblies that are designed for use in the DC to 40 GHz frequency range, intended to facilitate accurate measurements and exhibit low loss characteristics at a competitive price for precision test and measurement applications. The family is currently comprised of...
Read More

Memory Effect Reduction for LDMOS Bias Circuits

Memory effects have taken a very important role in today's design of base station power amplifiers. For example, they are responsible for limiting the cancellation when pre-distortion is applied to a power amplifier system.1 This study show...
Electrical memory effects are defined as changes in amplitude and phase of distortion components caused by modulation frequency. There are several ways of measuring memory effects. One of the most common is to plot the phase and amplitude of the distortion parameters with respect to the tone spacing in...
Read More

A Low Noise Wideband Microwave Oscillator Using a Tunable Microstrip Combline Filter

In RF measurement equipment, microwave synthesized signal sources, broadband digital satellite receivers and many other applications, broadband and low phase noise oscillators are becoming more and more important. A wide tuning range and good phase noi...
Typical oscillator designs use a common-base or common-collector circuit for generating a negative resistance at one port, which is usually terminated with a parallel or series LC-resonant circuit. The main problems in this design are the bandwidth of the negative resistance, which cannot be easily extended over one frequency...
Read More

A Method to Predict the Level of Intermodulation Products in Broadband Power Amplifiers

This article derives a formula to mathematically predict the level of intermodulation products generated in a broadband, multi-carrier power amplifier. The prediction method uses the level of a harmonic as a reference from which to extrapolate the leve...
Multiple RF exciters feeding a broadband power amplifier and a broadband antenna system has become an increasingly popular form of system architecture throughout the frequency spectrum. This architecture, shown in Figure 1 , has several desirable features, the most popular of which is the reduced real estate requirement. Modern...
Read More