Accession Number:

ADA327355

Title:

An Investigation of the Sources and Characteristics of the Noise Component in SeaMarc II Echo Signals.

Descriptive Note:

Final rept.,

Corporate Author:

HAWAII UNIV HONOLULU SCHOOL OF OCEAN AND EARTH SCIENCE AND TECHNOLOGY

Personal Author(s):

• Zisk, Stanley

Report Date:

1996-01-28

Pagination or Media Count:

4.0

Abstract:

As is well known, the SeaMarc II towfish system was lost at sea during a scientific survey cruise in the Southern Ocean near the beginning of this project. Work was immediately begun on the design and construction of a replacement mapping system to be called HAWAII MR1. The signal processing for this system was designed based on the crude and incomplete information obtained earlier from one short series of noise measurements that had been made on SeaMarc II with experimental modifications. In the new MR1 system, the recorded signal consisted of digital, complex samples of the acoustic echo i.e. in-phase and quadrature components, referenced to transmitter sinusoidal waveform. The entire duration of the echo signal was recorded, including the entire water column reverberation and the subsequent seafloor echoes, usually out to 70 - 80 degrees incidence angle.

Descriptors:

• *ECHOES
• *MAPPING
• *ACOUSTIC RECORDING SYSTEMS
• SIGNAL PROCESSING
• ACOUSTIC WAVES
• REPLACEMENT
• NOISE
• REVERBERATION
• OCEAN BOTTOM
• DIGITAL RECORDING SYSTEMS

Subject Categories:

• Physical and Dynamic Oceanography
• Cartography and Aerial Photography
• Recording and Playback Devices

Distribution Statement:

APPROVED FOR PUBLIC RELEASE