Intermodulation Distortion in RF Connectors

Intermodulation distortion or IMD has always existed in RF transmission paths. Until about the early 1990’s, cellular communications had relatively low power carrier levels. Intermodulation distortion in passive devices was not necessarily a problem because the distortion levels were significantly below the noise floor of the broadcast system. The mobile communication industry grew rapidly and the need for greater channel capacity meant higher broadcast powers at base stations. Typical RF connectors such as the N connector satisfied the earlier demands but as the sensitivity of the receivers increased, a condition within RF connectors was exposed.