ASELSAN ZOKA-Acoustic Torpedo Countermeasure Jammers and Deceptors, ordered by Indonesia in 2019, reportedly arrived in Indonesia on 22 October 2020.
The first foreign order for ZOKA-Acoustic Torpedo Countermeasure Jammers and Deceptors, developed nationally by ASELSAN and used in all submarines in our navy, was received from Indonesia in 2019. The mixers and deceivers planned to be used in Nagapasa (Type 209/1400) class submarines in the inventory of the Indonesian Naval Forces Command arrived in Indonesia on 22 October 2020, as reported by the Janes site.
ZOKA Jammers and Deceptors have features to be effective against all torpedo threats that can operate in active, passive or combined mode with acoustic guidance. ZOKA Mixers and Deceptors are used in the HIZIR Surface Torpedo Countermeasure System and ZARGANA Submarine Anti-Torpedo Systems, and there are two different types of ZOKA Mixers and Deceptors, which are deceptive and confusing, in both systems.
ZOKA mixers broadcast broadband high-level noise to cover the acoustic operating frequency range of the torpedoes. In this way, while masking the submarine noise against passive torpedoes, they increase the ambient noise against active torpedoes and reduce the detection range of the signal reflected from the submarine. ZOKA deceivers, on the other hand, imitate the acoustic and dynamic characteristics of the platform and deceive the torpedo and pull it on itself. The deceivers have the functions of simultaneously generating ship noise and responding to the torpedo active broadcast while listening with their hydrophones pulled from behind.