Wireless communications under the water is a challenging task. Electromagnetic waves are absorbed too quickly by the water to send data beyond a few tens of meters. Free-space optical communication under the water, on the other hand, offers a small improvement in communication ranges in comparison to electromagnetics, but is hampered in high-visibility conditions, especially in shallow waters. This leaves acoustic waves as the most promising vehicle to transport data to distances greater than a few tens of meters under the water without using wires.
In acoustic communication, message content is first transformed into a sound wave and transmitted using transducers. A transducer is an underwater loud speaker. At the receiver site, received sounds are collected with hydrophones (microphones working under the water) and transformed back into electrical signals. The received data, however, are subject to a significant amount of distortion and corruption caused by the undersea propagation environment. The destructing effect of the underwater media has so far prevented acoustic communication modems from gaining a widespread acceptance as a reliable solution until Marecomms has developed the ROAM (RObust Acoustic Modem).
ROAM is a truly robust and broadband underwater acoustic communication system that offers the capability for wireless transmission of images, videos or sensor data under the water with unprecedented reliability.
ROAM has been tested in unforgiving waterways of Northern Atlantic in different temperature, salinity, and water depth conditions and has been proven to deliver several tens of kilobits per second throughputs in a vast variety of circumstances where typical modem design approaches are shown not to work. ROAM is built on a distinct approach to underwater sound propagation, which resulted in a solid theory that has eliminated implausible assumptions that are ordinarily relied on. As a result, ROAM does not depend on pristine conditions to work properly.
In our last sea trials performed in January 2020, the original version of the picture below was converted into a sound wave, which was wirelessly transmitted under the water at Bedford Basin, Nova Scotia, Canada. The received data were significantly distorted and corrupted by the underwater propagation environment as anticipated. Applying our algorithms to the raw received data, however, led to the re-constructed image shown below. As seen in the image, our algorithms restored a perfect replica of the original transmitted image (i.e., zero Bit Error Rate (BER)).
In these experiments, we reached a user-experienced data rate of 26.66 Kilobits per second in a challenging horizontal shallow water environment with random surface movement, where we used nearly 30 dB less sound level than typical values. Our current focus is on further increasing these data rates without a significant incline in the transmit sound levels. This will make it possible to transmit images and videos to a lateral reference distance of 1 Km with an acceptable latency.
Drop us a line at info@marecomms.ca and visit the Use Cases page to hear how our solution can alleviate your business pain.
In acoustic communication, message content is first transformed into a sound wave and transmitted using transducers. A transducer is an underwater loud speaker. At the receiver site, received sounds are collected with hydrophones (microphones working under the water) and transformed back into electrical signals. The received data, however, are subject to a significant amount of distortion and corruption caused by the undersea propagation environment. The destructing effect of the underwater media has so far prevented acoustic communication modems from gaining a widespread acceptance as a reliable solution until Marecomms has developed the ROAM (RObust Acoustic Modem).
ROAM is a truly robust and broadband underwater acoustic communication system that offers the capability for wireless transmission of images, videos or sensor data under the water with unprecedented reliability.
ROAM has been tested in unforgiving waterways of Northern Atlantic in different temperature, salinity, and water depth conditions and has been proven to deliver several tens of kilobits per second throughputs in a vast variety of circumstances where typical modem design approaches are shown not to work. ROAM is built on a distinct approach to underwater sound propagation, which resulted in a solid theory that has eliminated implausible assumptions that are ordinarily relied on. As a result, ROAM does not depend on pristine conditions to work properly.
In our last sea trials performed in January 2020, the original version of the picture below was converted into a sound wave, which was wirelessly transmitted under the water at Bedford Basin, Nova Scotia, Canada. The received data were significantly distorted and corrupted by the underwater propagation environment as anticipated. Applying our algorithms to the raw received data, however, led to the re-constructed image shown below. As seen in the image, our algorithms restored a perfect replica of the original transmitted image (i.e., zero Bit Error Rate (BER)).
In these experiments, we reached a user-experienced data rate of 26.66 Kilobits per second in a challenging horizontal shallow water environment with random surface movement, where we used nearly 30 dB less sound level than typical values. Our current focus is on further increasing these data rates without a significant incline in the transmit sound levels. This will make it possible to transmit images and videos to a lateral reference distance of 1 Km with an acceptable latency.
Drop us a line at info@marecomms.ca and visit the Use Cases page to hear how our solution can alleviate your business pain.
(We thank and acknowledge our project partners, Geospectrum Technologies for their continuous support in this project. In all our experiments, we used the state-of-the-art transducers and hydrophones built and provided by Geospectrum)
© 2020 Marecomms Inc.