experiment 2 measurements of s-parameters with the vector ... microelectronic… · faculty of...

Faculty of Information Engineering and Technology Communications Department Communication Lab COMM-606

Radio Frequency and Microwave Engineering

Experiment 2

Measurements of S-parameters with the

Vector Network Analyzer

Lecturer: Associate Prof. Hany Hammad

Assistants:

Eng. Shoukry Ibrahim Eng. Sandra Nelson

Eng. Nardeen Mounir Eng. Mohamed Salah

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Part II. Measurements of S-parameters with the Vector Network Analyzer

Principles: Network analysis is the process by which designers and manufacturers measure the electrical

performance of the components and circuits used in more complex systems. When these systems are conveying signals with information content, we are most concerned with getting the signal from one point to another with maximum efficiency and minimum distortion. Vector network analysis is a method of accurately characterizing such components by measuring their effect on the amplitude and phase of swept-frequency and swept power test signals.

• The S-parameters of passive and active networks can be measured with a vector network

analyzer, which is a two- (or four-) channel microwave receiver designed to process the magnitude and phase of the transmitted and reflected waves from the network under test.

• In operation, the RF source is usually set to sweep over a specified bandwidth. A four-port reflectometer samples the incident, reflected, and transmitted RF waves. A switch allows the network to be driven from different ports.

• Signals are converted to IF frequencies, which are then detected and converted to digital form.

• A powerful internal computer is used to calculate and display the magnitude and the phase of the S-parameters, or other quantities that can be derived from the S-parameters, such as the SWR, return loss, group delay, impedance, etc.

• Calibration procedures are done to account for errors caused by directional couplers mismatch, imperfect directivity, losses, and variations in the frequency response of the analyzer system.

This part of the experiment aims to investigate the principles of S-parameters measurements

using the vector network analyzer, including:

• Block diagram of the analyzer. • Calibration procedure (SOLT procedure). • Applications for some passive elements, such as power dividers.

The COM3LAB Computer Based Training (Microwave Technology I course) is used for this purpose based on the vector network analyzer 737 530.

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1-Microwave technology I equipments

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2-The Network analyzers

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3-The Block diagram

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4-The Device specification

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5-The program interface

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6- The Calibration process

6.1 Short circuit calibration

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6.1 Open circuit calibration

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6.3 Load calibration

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6.4 The Through calibration

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7- Test the calibration process

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Bibliography: [1] David M. Pozar, “Microwave Engineering”, third edition, John Wiley and Sons Inc. [2] Agilent AN 1287-1, “Understanding the Fundamental Principles of Vector Network Analysis”, application note, (http://cp.literature.agilent.com/litweb/pdf/5965-7707E.pdf ).

experiment 2 measurements of s-parameters with the vector ... microelectronic… · faculty of...

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