OVERVIEW: The Zoka system by ASELSAN comprises acoustic jammers and decoys designed to protect submarines and surface ships from active, passive, and hybrid acoustic-homing torpedoes. Deployed via 6-inch (approximately 150 mm) launch tubes or signal ejectors, its configurable payloads generate deceptive acoustic signatures and noise barriers to mislead incoming threats.

DETAILS:
The system includes two primary effectors:
-Zoka Jammer (ZOKA 100-S/ED): A broadband, high-power acoustic noise emitter covering the operational frequency ranges of modern torpedoes. It masks submarine noise (in passive mode) and disrupts echo-based detection (in active mode).
-Zoka Decoy (ZOKA 100-N/ED): Mimics the host vessel’s acoustic and dynamic signature using onboard hydrophones and signal generators. It provides realistic echoes in response to torpedo pings while adding deceptive movement, drawing threats away.
The effectors are pre-programmed before launch, enabling tactical flexibility. Launch platforms include ASELSAN’s Zargana submarine system and Hızır surface-ship system. Effects last subsurface up to ~1.9 km — enough to create time and distance for evasive maneuvers.

FONCTION:
Detect incoming torpedo using onboard sensors and countermeasure management system.
Launch Zoka effector (jammer or decoy) from a 6-inch launcher or signal ejector.
Emit broadband noise or simulated vessel acoustic signature and echoes to confuse or divert the torpedo.

SOURCE:
ASELSAN product pages for ZOKA 100-S/ED and 100-N/ED aselsan.com; defenceturkey.com Defence Turkey article on Zargana & Zoka deployment ; SavunmaSanayiST overview of Zoka roles