<p>A seabed exploration system comprising a self-contained underwater vehicle (10) comprising a sonar transmitter and linked to a main naval vessel (20). The sonar transmitter on the self-contained vehicle comprises a transmitting antenna (11) with electronic circuitry (12) coupled thereto to form coded and directional multichannel transmission in a sonicated bearing sector. Receivers (21,22) are carried on the main vessel and comprise detectors (21) for forming a dedicated receiving channel having a wide-bearing lobe and coupled to receiving circuitry (22) comprising a device (211) for separating the received codes. The system maintains the main naval vessel's security and may be used in seabed mine detecting systems.</p>
