Passive Inter Modulation (PIM) is a form of signal interference. It is usually caused by a number of carriers sharing the same downlink path in a wireless network. This is becoming more common as with multiple wireless networks and technologies operating at a single site. The signals from various technologies combine to generate interference which impacts the uplink signal. Antennas, cables, connectors and passive components can all be sources of PIM. Below are a list of white papers and application notes that talk about PIM.