Test and Measurement Channel

RSS

Cellular base station receivers work in the presence of high level blockers/interferers while being required to sense weak signals of interest at the antenna. The interferers are usually rejected by filters but only at an intermediate frequency (IF) after the first down conversion. The LNA and mixer preceding the...

The main criterion when an EM engineer uses modeling and design packages is that it should enable him to meet his daily challenges of designing new products that work in their intended environment. This is now becoming a reality with the advent of the Micro-stripes Version 6.1 3D-EM modeling...

Applied Wave Research Inc. (AWR™) has focused on an engineering effort to eliminate uncertainty in the high frequency design process by closing gaps in existing design methodologies and strengthening the links between system specifications and circuit performance, electrical design and physical layout, and computer simulation and RF measurements. This...

Creating single-emitter pulse patterns for testing radar receivers is a complex, time-consuming process because of the extensive mathematics required, whether creating the initial waveform, modifying any of its characteristics such as pulse shaping and compression, or creating custom pulse patterns. A comprehensive software application called Signal Studio for Pulse...

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...

Accurate, nonlinear, active device models are critical to achieving design success for circuits such as power amplifiers, oscillators and mixers, using computer-aided engineering (CAE) software such as Agilent Technologies' Advanced Design System (ADS™), Applied Wave Research's Microwave Office™, Eagleware's Genesys™ or Ansoft's Serenade™. Prior work has made it clear...

The rapidly increasing use of differential RF and microwave circuits has created many new measurement challenges. In S-parameter measurements, for example, transmission phase accuracy could often be ignored with little impact on specification-critical measurements. This is no longer true in the measurement of differential circuits, since seemingly small phase...

Coplanar waveguide probes, also referred to as coplanar probes, are the method of choice for launching RF signals on and off a wafer. This article explains their construction, RF characteristics and proper usage. Before the advent of coplanar probes, finding the RF behavior of a die on a wafer...

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...

For about half a century the suppression effects of bandpass hard limiters on various combinations of signals and interference have attracted widespread interest. 1-4 Certain "rules of thumb" have accreted around a variety of theoretical results. The purpose of this article is to revisit issues of interpretation and to...