I have a project that I am just starting to play around with and it would involve transmitting and receiving signals underwater over a range of up to, perhaps, 100 feet or so. I want to explore both an RF and an ultrasonic option. I know that RF signals are attenuated very heavily by water, particularly salt water, but I have no feel for whether transmitting low bandwidth signals over 100 ft using equipment that is suitable for personal use (think something that a scuba diver would use) is at all practical. On the ultrasonic side, my immediate concern is whether I need to use sensors that are specifically designed to be immersed or whether I can use cheap sensors inside a watertight enclosure and couple them to the water effectively.
Any thoughts or guidance from folks out there that have any kind of experience in this arena?
Any thoughts or guidance from folks out there that have any kind of experience in this arena?