IEC 62037-1-2012 pdf free

IEC 62037-1-2012 pdf free.Passive RF and microwave devices, intermodulation level measurement – Part 1: General requirements and measuring methods.
PIM interference is caused by sources of non-linearity of mostly unknown nature, location and behaviour. A few examples are inter-metallic contacts, choice of materials, corrosion products, dirt. etc. Most of these effects are subject to changes over time due to mechanical stress, temperature changes, variations in material characteristics (cold flow, etc.) and climatic changes, etc.
The generation of intermodulation products originates from point-sources inside a DUT and propagate equally in all available directions.
The generation of passive intermodulation products (PIM) does not necessarily follow the law of the usual non-linear equation of quadratic form. Therefore, accurate calculation to other power levels causing the intermodulation is not possible and PIM comparisons should be made at the same power level.
Furthermore, PIM generation can be frequency-dependent. When PIM generation is frequencydependant. the PIM performance shall be Investigated over the specified frequency band.
5 Principle of test procedure
Test signals of frequencies f and ‘2 with equal specified test port power levels are combined and fed to the OUT. The test signals should contain at least 10 dB less harmonic or selfintermodulation signal level than the expected level generated in the DUT.
The PIM is measured over the specified frequency range. The intermodulation products of order (2!., ± ‘2)’ (2(2 ± i) etc. are measured.
In most cases, the third order intermodulation signals represent the worst case condition of unwanted signals generated; therefore, the measurement of these signals characterizes the DUT in a sufficient way. However, the test set-ups given in Clause 6 are suitable for measuring other intermodulation products.
In other systems (such as CATV), the 3rd order may not be as applicable in characterizing the
DUT.
Intermodulation can be measured in reverse and forward direction. Reverse and forward is referred to the direction of propagation of the most powerful carrier.
6 Test set-up
6.1 General
Experience shows that the generation of intermodulation products originates from point- sources inside a device under test (OUT) and propagates equally in all available directions. Therefore, either the reverse (reflected) or the forward (transmitted) intermodulation signal can be measured.
Two different test set-ups are described in Figure 1 and Figure 2 and are for reference only. Other topologies are possible.
Set-up 1 is for measuring the reverse (reflected) intermodulation signal only, and set-up 2 is for measuring the forward (transmitted) intermodulation signal. The measurement method (reverse or forward) is dependent upon the OUT. The set-ups may be assembled from standard microwave or radio link hardware selected for this particular application. All components shall be checked for lowest self-intermodulation generation.
Experience shows that devices containing magnetic materials (circulators, isolators, etc.) can be prominent sources of intermodulation signal generation.
See Annex B for additional set-up considerations.IEC 62037-1 pdf free download.