Underwater Sensor Basics: Types, Applications, and Manufacturers

This page covers the basics of underwater sensors, including an application note and a list of vendors/manufacturers. As the name implies, underwater sensors are used to gather information about the underwater environment.

Underwater vehicles enhance the capabilities of these sensors by providing data retrieval, connectivity, and network management. Due to the unique requirements of underwater communication, specialized underwater sensors have been developed.

Underwater Sensor Application

Figure 1: Internal architecture or block diagram of an underwater sensor.

As shown in the figure, a typical underwater sensor consists of the following major modules/components:

• Sensor
• Power Supply
• Memory
• CPU
• Acoustic Modem
• Sensor interface circuit

These devices are used to measure water quality, including characteristics like temperature, salinity, density, acidity, conductivity, chemicals, oxygen, pH, hydrogen, turbidity, and dissolved methane gas.

Types of Underwater Sensors

Here are some common types of underwater sensors:

• Interferometric and refractometric sensors
• Magnetoelastic sensors
• Clark-type electrode
• Disposable sensor (detects ricin)
• Hydrothermal sulfide, voltammetric sensors for spectrophotometry, silicate, and gold-amalgam electrode sensors
• Amperometric microsensors for $H_2S$ measurements
• Force and torque sensors
• Quantum sensors to measure light
• Sensors to measure harmful algal blooms

Underwater modems typically operate at depths of 120 to 200 meters, with a communication range of about 3 Km and a communication rate around 7 Kbps.

Underwater Sensor Manufacturers or Vendors

The following table lists manufacturers and vendors of underwater sensors and acoustic modems: