Monitoring littoral seas without being detected can be desirable in times of conflict. In such cases, autonomous submersible monitoring and communications systems can provide much needed intelligence. While such devices can be deployed without detection, communicating the results of monitoring by devices submerged in the sea is problematic. Sonar provides low bandwidth over short ranges and radio communications, at all but the highest powers and lowest data rates, are blocked by salt water. Effective communication requires therefore that an antenna be raised above the sea. A variety of systems have been described for raising an antenna above the sea, but they are either expensive, impractical, or readily detected, making them unsuitable for exporting information without being detected.