RPV Pioneer abroad USS Iowa-an EMI case history

The author reviews the two-year history of RDT&E (research, development, test, and evaluation) EMI (electromagnetic interference) control efforts provided by the US Navy´s Shipboard Electromagnetic Compatibility Improvement Program (SEMCIP) to support introduction into the fleet of the remotely piloted vehicle (RPV) Pioneer. The effort encompassed fifteen test events from August 1986 to March 1989. Special EMI problems resulted from the `off-the-shelf´ or non-developmental item status of Pioneer. Other significant issues involved signal generation and processing, ship-system interactions, and application of radar absorbing material and ship barriers for systems isolation. It is concluded that the below-decks control station test environment specified in MIL-STD-461 should be raised from 12.75 V to about 30 V (6 dB above expected worst case). Further testing should be accomplished to determine what source impedance constraints (or power) might be appropriate to accompany this new MIL-STD-461 requirement