Directional Acoustic Transducers (Echo Sounders)

directional acoustic transducer (sx18-00)

Sensor Technology Ltd. has designed a wide range of directional acoustic transducers over the past 30 years, including ultrasonic transducers from 20 kHz to 2 MHz. Common uses include single beam and multi-beam transducers for hydrographic survey and split beam transducers for fish finding, but the applications are actually quite broad. Echo sounder transducers are often used in either send & receive (echo sounding) or send-only modes for acoustic telemetry, pinger/transponder networks, navigation and underwater positioning.

Ultrasonic transducers are also increasingly common in non-marine environments and can be found controlling production lines or industrial systems, acting as proximity sensors, fluid level sensors and gas/fluid flow meters.

Customizing Directional Acoustic Transducers

Echo sounding uses the timing of a returning echo to determine the distance to a target. echo sounder vertical resolution is determined by frequencyTargets positioned closer together than one wavelength will create echoes that the system perceives as a single return. This will be interpreted as a single target. Given that the wavelength is a function of frequency, it is the operating frequency of directional acoustic transducers that determines vertical resolution.

 

echo sounder horizontal resolution is determined by beam width

Similarly, if multiple objects produce multiple echoes with a similar return timing, the system will perceive a single return and indicate a single target. A narrow beam can be used to reduce the potential for multiple returns. So, the directionality (i.e. beam width) of an echo sounder determines horizontal resolution.

The operating frequency and beam angle are both customizable, which is why directional acoustic transducers are so versatile. We can use Langevins, mass loaded elements, monolithic piezoelectric ceramics and 1-3 piezo composites to meet the exact performance specifications of your application. Key variables that can be adjusted to meet your requirements include:

  • Operating frequency
  • Beam angle
  • Bandwidth
  • Operating depth
  • Packaging (e.g. housing, mounting points, cable/connector type)

The possibilities are virtually endless. Contact us to discuss your requirements.