Building An Acoustic Modem

Two words, underwater communication.The project goal was to build an acoustic modem for underwater communication to be used by our sponsor, SDSU Mechatronics. Mechatronics requires this system to enable their autonomous mother and daughter submarines to communicate with each other under the water during the AUVSI 2017 RoboSub competition. The two submarines enable the Mechatronics’ team to complete underwater obstacles in a short amount of time.

The project was divided into two sub groups, hardware and software. The software team was responsible to create a graphical user interface (GUI) and an interactive underwater simulation to generate data. The GUI must also apply error correcting schemes on the data received and provides live plotting.

The hardware team had to receive data from the software team and send it across a body of water (a fish tank or a swimming pool). The hardware team achieved this goal by generating frequencies using a DDS modulator, amplifying the signal and driving the transducers.

After the data is received by the transducer, it is passed through a bandpass filter and amplified through a variable gain amplifier. The signal is then enveloped by the precision envelope detector and converted to digital using an ADC. Once the microcontroller has sampled and processed the whole packet of data (96 bits) it is passed to the receive GUI. The team was able to successfully send, receive, and process packets of data within the semester time frame.


Our Amazing Team

Sebhat Yidelwo

Editor (Hardware)

Trevor Blazek

Editor (Software)

Brady Anderson

Hardware Project Manager

Nutdanai Swangpattaraphon

Hardware Secretary

John Salamat

Historian/Media

Emmanuel Palafox

Parts requisition

Uros Obradovic

Power Point

Leban Ali

Power point (hardware)

Blair Chantrill

Repository Manager

Davy Phakdy

Repository Manager

Shideh Naderi

Software Project Manager

Bao Hoang

Team Logo Design

Jeffrey Miller

Technical Manager

Jonah Mariano

Technology Illustrator

Mark Dimaano

Web Design

Cavan Page

Web Design