Test and Measurement Channel

High Performance Comb Generator Multipliers

A new line of comb generator multiplier products is featured
A comb generator is a device with outputs that are multiple harmonics of an input signal. The output spectral tone lines are uniformly spaced at integer multiples of the input reference. A spectrum analyzer display of the output looks much like the teeth of a comb, which is how...
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Specification and Measurement of Local Oscillator Noise in Integrated Circuit Base Station Mixers

Residual phase noise from local oscillators can be degraded by additive noise of on-chip local oscillator (LO) drivers/buffers in integrated circuit mixers. Reciprocal mixing of strong RF signals with the LO noise degrades the receiver sensitivity. Spe...
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...
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An Enhanced 3D-TLM Solver

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...
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Software for Creation of Custom Radar Pulse Patterns

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...
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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...
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Pulsed I-V for Nonlinear Modeling

Current-voltage characterization under suitably performed pulsed bias conditions can more closely approximate the dynamic behavior of transistors and diodes under large signal RF conditions. Some understanding of the basics and a relatively simple inst...
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...
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The Importance of Phase Accuracy in Differential VNA Measurements

The impact of phase errors in vector network analyzer measurements has become more significant with the increased use of balanced devices and non-50 Ω reference impedances. These significant phase errors are often traceable to calibration or de-em...
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...
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RF Coplanar Probe Basics

Explanation of the construction, characteristics and usage of coplanar waveguide probes
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...
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