The SonarBell® is very effective at capturing the sound energy produced by a sonar and directing a large proportion of that energy back towards the sonar. This is important as the more energy the SonarBell® captures and reflects back at the sonar, the greater the range and the clearer the target for display by the sonar.
Note, the SonarBell® does not generate energy itself nor does it draw on a power supply, it is simply an effective reflector of the energy put into the water by a sonar.
The Effective Range over which the SonarBell® will be seen is a function of several factors including:
- The proportion of energy sent out by the sonar reflected by the SonarBell® (a function of SonarBell® efficiency).
- The overall amount of energy hitting the SonarBell® (a function of SonarBell® size).
- The environmental conditions in the water (environmental noise for example).
- The total amount of energy put into the water by the sonar.
If we consider those aspects of performance directly influenced by the SonarBell®.
Efficiency of the SonarBell®
A typical 200mm SonarBell® tuned for a single peak response will have a target strength of between -5 and -10db, it therefore reflects between 32% and 10% of the power that hits it, depending on the specific frequency of resonance.
Size of the SonarBell®
The bigger the SonarBell® the more energy it captures, thus the larger the energy signal sent back to the sonar, the larger the range over which it will be seen. A 100mm SonarBell® will have a range that is about a third to a quarter that of the 200mm SonarBell®.
SonarBell® Response Bands
The response of a SonarBell® can be tuned in terms of frequency and amplitude to deliver:
- Single narrow band resonance
- Multiple high strength resonance peaks
- Broadband response