IEC 61830:1997 pdf download – Microwave ferrite components – Measuring methods for major properties.
IEC 61830 gives guidance on the measuring methods br major microwave properties, such as return loss, forward loss, reverse loss, phase shift and group delay, of microwave ferrite components.
NOTE I — The methods of measurement ate compiled after the model 01 IEC 6D510-l -3,
NOTE 2 — N.lwodr analyzers Cr. b.in used by nest manutaciurers to evaluate such properties ol microcave territe components at present However, know4ede of basic measunng methods is necessary br understandinQ the geneval purpose 04 measuiements including the use 01 network analyzers. Theretore, orthodox methods 01 measurement ar, described hrin
2 NormatIve reference
The following normative document contains provisions which, through reference In this teat, constitute provisions of this standard. At the time of publication, the edition indicated was valid. All normative documents are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent edition of the normative document indicated below. Members of IEC and ISO maintain registers of currently valid International Standards.
IEC 60510-1-3: 1960, Methods of measurement for radio equipment used in satellite earth
stations — Part 1: Measurements common to sub-systems and combinations of sub-systems — Section three: Measurements in the I.!. range
Amendment 1 (1988)
3 Return loss
3.1 The relationship between impedance, return loss, reflection coefficient and voltage standing wave ratio (VSWR)
In microwave ferrite components. interest is essentially in the measurement of return loss rather than that of impedance. reflection coefficient, or VSWR.
3.2 Method of measurement of return loss
Measurements may be made by using either point-by-point or sweep-frequency methods. For the latter case, an example is described in following subclauses. but any alternative method capable of providing the required accuracy (typically ±1 dB) may be used. In this example, the equipments listed below and shown in figure 1. are needed:
— a sweep frequency generator;
— a microwave bridge;
— a calibrated attenuator;
— an amplitude detector;
– an oscilloscope.
The method is intended for measuring the return loss of linear and passive ports, for example the input impedance of an isolator. It also may be used for measuring the return loss of linear. active and passive devices, for example at the output of device (source Impedance) provided that no signal is present and that the device under test can be considered as a linear, passive network.
The return loss of cables, attenuators, adapters. etc.. used during the measurements, as well as the return loss at the input and the output of measuring equipment, may be checked using the same method.
3.3 General considerations of the measuring equipment
3.3.1 Sweep-frequency generator
Over a specified frequency iange, the generator should be able to generate a sinusoidal, radio
frequency signal, and its output level should be constant.
The repetition rate f of the sweep should be In the range 10 Hz to tOO Hz provided that the passband of the receiver section, i.e.. amplitude detector and oscilloscope, is about 50 times to 100 times the chosen sweep rate.
3.3.2 Microwave bridge
Over a specified range of signal levels, the voltage at the output of the bridge should be proportional to the magnitude of the reflection coefficient of the impedance under test.
3.3.3 Detector sensitivity
The minimum level detectable by the detector should be at least 20 dB below the minimum level expected from the bridge under conditions given in 3.4.3.
