Re: kilohertz conversion with water depth

Re: kilohertz conversion with water depth   (10/22/2006, 12:54 PM)

I assume you are referring to sonar systems to measure water depth. You can search Google for more information.

Signal frequency - Varies based on the transducer and model, generally between 12 and 450 kilohertz (kHz). The frequency determines the depth capabilities of the system.

Higher frequency (100 to 450 kHz) for shallower waters (<10 to 300 meters)
Medium frequencies (30 to 100 kHz) for medium-depth waters (300 to 3,000 meters)
Low frequencies (12 to 18 kHz) for very deep waters (6000+ meters)

[ from https://en.wikipedia.org/wiki/Sonar ]

Sonar operation is affected by sound speed. Sound speed is slower in fresh water than in sea water. In all water sound velocity is affected by density (or the mass per unit of volume). Density is affected by temperature, dissolved molecules (usually salinity), and pressure. The speed of sound (in feet per second) is approximately equal to 4388 + (11.25 x temperature (in degrees F)) + (0.0182 x depth (in feet) + salinity (in parts-per-thousand)). This is an empirically derived approximation equation that is reasonably accurate for normal temperatures, concentrations of salinity and the range of most ocean depths.