Patent ID: 7308202
Filing Date: 2007-12-11
Classification: F41G,G01S,H04L

Abstract:
1. A method for identifying, as friend or foe, a combat response unit having a helmet-mounted challenge receiver and retroreflector obturator, the method comprising the unordered steps of: (a) projecting an infrared (IR) transmit signal including a transmitted code of the day (TCOD) encoded as pulse positions within a predetermined frame interval onto the combat response unit from a combat interrogatory unit; (b) receiving the IR transmit signal and TCOD at the challenge receiver; (c) selectively reflecting the IR transmit signal to modulate the reflected signal by opening and closing the retroreflector obturator according to a response code of the day (RCOD); (d) receiving the reflected IR transmit signal and RCOD at the combat interrogatory unit; and (e) combining the received RCOD with the TCOD to identify the combat response unit as friend or foe.