Patent ID: 7831150
Filing Date: 2010-11-09
Classification: F41G,G01S,H04L

Abstract:
1. A combat interrogatory unit for use in a combat identification as friend or foe (IFF) communications system, the combat interrogatory unit comprising: projector means for projecting an infrared (IR) transmit signal including a transmitted code of the day (TCOD) encoded as pulse positions within a predetermined frame interval; means for determining a proper closed-shutter interval of an expected response to the projected IR transmit signal based on the TCOD and at least one datum not included with the TCOD, said closed-shutter interval being variable according to the TCOD; receiver means for receiving a reflected IR transmit signal including a response code of the day (RCOD); and means for identifying a source of the reflected IR transmit signal as friend or foe, wherein the source is identified as friend or foe based on a comparison between the closed-shutter interval of the expected response and a corresponding delay interval of the RCOD.