What does PIM testing mean?
An on-site PIM test is a comprehensive measure of linearity and construction quality. PIM shows up as a set of unwanted signals created by the mixing of two or more strong RF signals in a nonlinear device, such as a loose or corroded connector, or nearby rust.
What is PIM and sweep testing?
Line sweeping measures the signal losses and reflections of the transmission system. PIM testing is a measure of construction quality and poor quality will result in self-interference. PIM testing performance measurements are not relevant unless accompanied by comprehensive line sweep tests.
What test instruments can be used to find PIM?
PIM testers or analyzers are sophisticated forms of test equipment. While a PIM test system can be assembled from signal generators and a spectrum analyser together with a few other components, specialised PIM testers are often needed because testing is undertaken in situations such as cellular base station sites, etc.
How can PIM be minimized or eliminated?
The good news is that there are ways to minimize the impact of PIM in DAS. The obvious ones are to 1) avoid frequency combinations that place low order IM product(s) in Rx band(s); 2) reduce site Tx power, or 3) improve the linearity of the system.
What is Pim hygiene?
Select Subcategory. Passive intermodulation (PIM) arises when there are two or more signals present in a passive non-linear device. Interference caused by PIM decreases a cell’s receive sensitivity and can block phone calls completely.
What is PIM in wireless?
At a basic level, PIM is the result of unwanted signals created by mixing of two or more frequencies in a non-linear passive device. These new signals interfere with and distort the original signal passing between two wireless systems. It can create signal interference in any wireless system.
What is cable sweep?
Sweep testing is the simple process of putting a whole bunch of signals through a cable and making sure that what you get out on the back end is within tolerances when compared with what you put in on the front end. As signals get higher in frequency, they have more loss over distance.
What does a PIM system do?
A PIM solution provides a single place to collect, manage, and enrich your product information, create product catalogs, and distribute information to your sales and eCommerce channels.
What conditions must exist to produce PIM?
Q: What conditions are necessary to cause PIM? A: Typically, two relatively strong RF signals relatively close in frequency are required to trigger PIM effects. The outputs from two or more high-power (20 W or so) transmitters are enough to create the PIM effects.
What is low PIM attenuator?
A Low PIM coaxial attenuator is an electronic device precisely designed to reduce the power of a RF signal without disturbing or decreasing the waveform of the signal significantly, and is able to block out unwanted signals generated by the non-linear mixing of 2 or more frequencies.
What is a PIM solution?
A Product Information Management (PIM) solution provides a single place to collect, manage, and enrich your product information, create a product catalog, and distribute it to your sales and eCommerce channels.
What is PIM testing for cellular systems?
Testing for PIM. PIM lowers the reliability, capacity and data rate of cellular systems. It does this by limiting the receive sensitivity. In the past, RF engineers could select channel frequencies that would not produce PIM in the desired receive bands.
What is PIM and how does it affect your network?
PIM is a growing issue for cellular network operators. PIM issues may occur as existing equipment ages, when co-locating new carriers, or when installing new equipment. PIM is a particular issue when overlaying (diplexing) new carriers into old antenna runs.
What cable faults show up best with a PIM test?
Some cable faults show up best with a PIM test. For example, if an antenna feed line has a connector with metal chips floating around inside, it is highly likely that it will fail a PIM test while the line sweep passes.
Why is PIM testing critical for high-speed digital communications?
High-speed digital data communications make PIM testing critical. As cell usage and throughput grows, the peak power produced by the new digital modulations increases dramatically, contributing heavily to PIM problems. On-site experiments have shown significant decreases in download speeds linked to slight increases in PIM.
