Network, Spectrum, and, Impedance (3 parcial)

Network, Spectrum, and, Impedance

Evaluation of Electronic Circuits and

Components

Introduction

With the current trends requiring higher performance, smaller physical size, lower cost, and higher reliability, fast cycle time is an increasingly important part of the product design. This is true not only in the consumer industry, but also in the communica­tion and data processing industries.

As shown in Figure 1, the develop­ment procedure involves designing the overall architecture, evaluating electronic components, building pro­totypes, and evaluating circuit per­formance. From the design point of view, it is essential to measure the impedance characteristics of electron­ic components such as capacitors, inductors, or other devices at the actual working condition. An imped­ance analyzer makes this task easy.

After making a prototype, a review of the circuit operation requires meas­urement of the following parameters: harmonics, noise, transmission char­acteristics, and reflection characteris­tics. The vector network analyzer, and the spectrum analyzer must be used for making these measurements. The Agilent Technologies 4395A/4396B Network/Spectrum/'Impedance Analyzer Family combines three ana­lyzer functions in one instrument. This application note describes how the 4395A/96B can be used to contri­bute fast cycle time for product development.

The Agilent Combination Analyzers have the following features

Three analyzers in One box As the name implies, the Agilent 4395A/4396B Network/Spectrum/ Impedance Analyzer Family can per­form vector network, spectrum, and (optional) impedance measurements. The combination analyzer family does not compromise vector network, spec­trum, or impedance performance. It is a breakthrough in test instruments, giving you outstanding performance as a full-capability combination ana­lyzer. Precision measurements and improved efficiency are possible with minimal training. Compared with using separate instruments, the 4395A/96B will save equipment cost and bench space.

Vector Network Analyzer Performance The Agilent Combination Analyzer Family offers you fast measurement with wide dynamic range. Transmis­sion and reflection data can be pro­vided with an optional Reflection/ Transmission Test Set or optional S-Parameter Test Set. As a vector net­work analyzer, the 4395A operates from 10 Hz to 500 MHz. The 439615 operates from 100 kHz to 1.8 GHz.

Spectrum Analyzer Performance The Agilent Combination Analyzers, designed with new digital techniques, outperform the traditional analog spectrum analyzer. Agilent's Combina­tion Analyzers feature a Fast Fourier Transform (FFT) digital-signal pro­cessing (DSP) technique for 20 to 100 times faster narrow-band spectrum measurement, when compared with swept-tuned spectrum analysis. The Agilent analyzer's stepped FFT technique (4395A: all RBWs, 4396B: 1Hz to 3kIIz RBW) breaks the speed barrier to give you lower noise floors without sacrificing speed. In addition, low phase noise provides improved signal resolution. Option 1D6 (The Time-Gated Spectrum Analysis Function) performs accurate burst signal analy­sis for burst-modulated signal evalua­tion. As a spectrum analyzer, the 4395A operates from 10 Hz to 500 MHz. The 4396B operates from 2 Hz to 1.8 GHz.

Impedance Analyzer Performance

When equipped with Option 010 and the Agilent 43961 A. Combination Analyzers can perform direct imped­ance measurements. Measurement parameters such as IZI, 9, C, L, Q, D, and more can be displayed directly on the color display. A built-in lumped equivalent circuit function aids cir­cuit modeling and simulation. As an Impedance Analyzer, the 4395A oper­ates from 100 kHz to 500 MHz. The 4396B operates from 100 kHz to 1.8 GHz.

Other Useful Functions

IBASIC, a subset of the HT BASIC programming language, is included with the standard 4S95A/96B. IBASIC is extremely powerful and easy to use. It can be used for automated testing, analysis of measurement results, or control of external equip­ment via GPIB. Files such as instru­ment state files, TIFF files, and data files can be transferred via GPIB to the controller/PC Qaost), which can easily manipulate the files. Usability and productivity are improved through features such as the DOS supported Floppy Disk Drive, the list sweep function, the marker function, and the limit line function.

Agilent Combination Analyzer Family Measurement Examples

The Combination Analyzer Family is a powerful tool for effective evalua­tion of electronic circuit and device performance. The following shows you some examples of measurements made by the combination analyzers.

Amplifier Evaluation Amplifier characterization requires the evaluation of a variety of meas­urement parameters via vector net­work analysis and spectrum analysis. Figure 2 shows the major measure­ment parameters for amplifier evaluation.

Network Evaluation for Amplifier The measurement configuration for network analysis of an amplifier is shown in Figure 3. Either an optional Reflection/Transmission test set or an optional S-parameter test set is required to perform this analysis

Gain and Phase Measurement

The amplifier gain is defined as the ratio of the amplifier output power (delivered to a Z₀ load) to the input power (delivered from a Z<> source), where (Z.,) is the characteristic impedance of the system. The Ampli­fier gain is most commonly specified as a typical or minimum value over a specified frequency range, while assuming that input and output sig­nals are in the amplifier's linear oper­ating range. Figure 4 shows the gain and phase measurement result of an amplifier.

Pagina fuente:

http://cp.literature.agilent.com/litweb/pdf/5967-5942E.pdf

Nombre: Josmar Eduardo Depablos Rodriguez

Asignatura: Circuitos de alta frecuencia