The present invention provides an autonomous weapon system (1) for improved guidance of a projectile for homing a target, the system (1) comprises a guided projectile (3) comprising at least one sensor (33) and a carrier projectile (2) and at least one guidance and reconnaissance unit (A) comprising a transmitter (11) for communication via light. The system use emitted light for both positioning and communication of target coordinates which provides an accurate and cost effective system for combatting point and surface targets by indirect fire.