This module introduces the active sonar problem for ambient noise that has constant power across the sonar receiver bandwidth. The result is a likelihood ratio of the ping history that includes a matched filter.
In this activity, students will experience echolocation themselves. They actually try echolocation by wearing blindfolds while another student makes snapping noises in front of, behind, or to the side of them.
Students are introduced to sound energy concepts and how engineers use sound energy. Through hands-on activities and demonstrations, students examine how we know sound exists by listening to and seeing sound waves. They learn to describe sound in terms of its pitch, volume and frequency. They explore how sound waves move through liquids, solids and gases. They also identify the different pitches and frequencies, and create high- and low-pitch sound waves.
The marine environment is unique and requires technologies that can use sound to gather information since there is little light underwater. The sea-floor is characterized using underwater sound and acoustical systems. Current technological innovations are allowing scientists to further understand and apply information about animal locations and habitat. Remote sensing and exploration with underwater vehicles allows scientists to map and understand the sea floor, and in some cases, the water column. In this lesson, the students will be shown benthic habitat images produced by GIS. These imaged will lead to a class discussion on why habitat mapping is useful and how current technology works to make bathymetry mapping possible. The teacher will then ask inquiry-based questions to have students brainstorm about the importance of bathymetry mapping.
Describes active sonar echo, direct blast and reverberation generation.
This course is an introduction to the fundamental aspects of science and engineering necessary for exploring, observing, and utilizing the oceans. Hands-on projects focus on instrumentation in the marine environment and the design of ocean observatories for ocean monitoring and exploration. Topics include acoustics, sound speed and refraction, sounds generated by ships and marine animals, sonar systems and their principles of operation, hydrostatic behavior of floating and submerged bodies geared towards ocean vehicle design, stability of ocean vessels, and the application of instrumentation and electronics in the marine environment. Students work with sensor systems and deploy them in the field to gather and analyze real world data.
Introductory subject for students majoring or minoring in ocean engineering and others desiring introductory knowledge in the field. Physical oceanography including distributions of salinity, temperature, and density, heat balance, major ocean circulations and geostrophic flows, and influence of wind stress. Surface waves including wave velocities, propagation phenomena, and descriptions of real sea waves. Acoustics in the ocean including influence of water properties on sound speed and refraction, sounds generated by ships and marine animals, fundamentals of sonar, types of sonar systems and their principles of operation.
Introductory subject for students majoring or minoring in ocean engineering and others desiring introductory knowledge in the field. Physical oceanography including distributions of salinity, temperature, and density, heat balance, major ocean circulations and geostrophic flows, and influence of wind stress. Surface waves including wave velocities, propagation phenomena, and descriptions of real sea waves. Acoustics in the ocean including influence of water properties on sound speed and refraction, sounds generated by ships and marine animals, fundamentals of sonar, types of sonar systems and their principles of operation.
Historically, sea floor mapping occurred with a more simple data collection method: soundings. Soundings are taken by dropping a weight with a pre-measured rope off the side of the boat and noting the measurement on the rope when the weight hits the bottom. This activity will replicate the creation of sea floor bathymetry by taking a simplified form of soundings in the classroom.
The marine environment is unique and requires technologies that can use sound to gather information since there is little light underwater. The sea-floor is characterized using underwater sound and acoustical systems. Current technological innovations are allowing scientists to further understand and apply information about animal locations and habitat. Remote sensing and exploration with underwater vehicles allows scientists to map and understand the sea floor. Similar technologies also aid in animal tracking, a method used within science and commercial industries. The teacher will use inquiry-based learning techniques to teach students the importance of habitat mapping and animal tracking.
Learn more about remote sensing.
In this lesson, students learn about echolocation: what it is and how engineers use it to "see" things in the dark, or deep underwater. Also, they learn how animals use echolocation to catch their dinner and travel the ocean waters and skies without running into things.
This course reviews the signal and information processing theory needed for sonar processing. The fundamentals of detection, localization and classification are presented.
This animation from the NOVA Web site describes how sonar uses sound waves to "see" underwater.
The Sound and Light unit provides students with an understanding of sound and light waves through the theme of the "Sunken Treasure," a continuous story line throughout the lessons. In Lessons 1-5, students learn about sound, and in Lessons 6-10, they explore the concepts of light. The first lesson introduces the concepts of longitudinal and transverse waves. Students then move on to the concepts of wavelength and amplitude in transverse waves. In the third lesson, students learn about sound through the introduction of frequency and how it applies to musical sounds. Next, girls and boys learn all about echolocation what it is and how engineers use it to "see" things in the dark, or deep underwater. The last of the five sound lessons introduces acoustics, in which students learn how different materials reflect and absorb sound.
