The general architecture of a sub-bottom profiler suitable for very shallow waters (<20 m) was defined for use on the coastal launch Haliotis.
The receiver array is separate from the transmitter array to ensure operation in very shallow waters while using frequency-modulated signals of sufficient duration. It uses low frequency, provides excellent vertical resolution, and can acquire data at speeds of up to 7 knots.
Transmitter levels are compatible with a penetration of approximately 20 m.
Example for a water height of 10 m
- Water height: 1–30 m
- Penetration: ~25 m in loose sediment
- Vertical resolution: ~25 cm
- Transmission level: 193 dB ref. 1 µPa at 1 m
- Electronics: Enertest linear 500 VA
- Signal: Chirp 1700-5500 Hz from 10 to 50 ms
- Acquisition speed: up to 7 knots