Real-Time Image and Status Transmission from a UUV during a Ship Hull Inspection in a Port Environment using a High-Speed High-Frequency Acoustic Modem

A one-way, high-speed, high-frequency acoustic modem (HS-HFAM) operating between 260 kHz and 380 kHz has been developed to transmit compressed underwater images and status information in real-time. High data rates are made possible using a high-resolution decision feedback equalizer with parallel algorithm for tracking and compensating large Doppler. Previous experimental results have shown that this modem achieves 13298.2 information bits per Joule at 87768 information bits per second and at a range of 88 m in ports and shallow waters. More recently, the HS-HFAM has shown very promissing results during a series of under-hull inspections using a Lockeed-Martin Cetus-II vehicle and conducted at SPAWAR in San Diego, California. These tests were followed shortly thereafter with a series of demonstration during the AUV Fest 2007 event at NSWC in Panama City, Florida. During these tests, the same Cetus-II vehicle and the BlueFin HAUV-1 vehicle were equipped with the FAU HS-HFAM and conducted multiple hull inspections successfully.