Echoes product line: technological advances offering new levels of data quality in Sub-bottom Profiling

iXblue counts more than 30 years of experience in the field of underwater acoustics. Based on this expertise, iXblue has built a robust and diverse range of sub bottom profilers with frequencies ranging from 200 Hz to 15 kHz. This is the Echoes product line.

One of the major assets of these high resolution sub-bottom profilers is the use of frequency modulated techniques, also known as CHIRP compression, which represents the state of the art technology in this field.

It provides an optimal compromise between transmitted power and vertical resolution. CHIRP sub bottom profiler performance strongly depends upon the transmitted signal bandwidth. From that perspective, the whole transmission chain from electroacoustic transducer to impedance matching and power amplifier must not exhibit any holes or bumps in the frequency band of interest. Because this rule is rigorously respected, the iXblue “True Flat Spectrum” technology outperforms the market and delivers unique sub bottom profile quality.

“True Flat Spectrum” technology allows ideal sediment interface response, close to theoretical, with optimal contrast and signal-to-noise ratio. The figure shows the sediment interface response for two systems having same bandwidth with different spectrum flatness.

Echoes 3500 T7: The Full Depth Oceanic SBP
Hull mounted Echoes 3500 T7 deliver outstanding performance and provide high quality data, resolving sediment layers down to 5,000 m depth with penetration down to 100 m as illustrated on the following images.
This system equips more than 10 high grade research vessels all over the world with full depth capability, typical penetration of 100m and resolution of 20cm. Echoes 3500 T7 exists in 4 and 6kVA version.

Yves Le Gall, Acoustic Director of French Institute IFREMER says:
“I can confirm that Ifremer purchased three Echoes 3500 T7 sub-bottom profiler systems in 1999, 2005 and 2009. The Echoes 3500 T7 systems are installed respectively onboard Le Suroît, Pourquoi Pas ? and L’Atalante and operated with great success. I can also bear witness to the fact that the systems appear to be very reliable and provide excellent data. As evidence of reliability, the SBP onboard Le Suroît is still operational after 15 years of regular use, performing shallow water to deep sea surveys (up to 5,000 m) worldwide.”

Echoes 3500 T3 / T1: Continental shelf and coastal portable versatile SBP
When it comes to continental and coastal geophysics applications, good portability and flexibility are required in addition to data quality. Optimized antenna and Class D compact power amplifiers form the core of the technology of the ECHOES 3500 T3/T1. This high-level quality SBP can be pole or hull-mounted.

The compactness of the system relies on extremely high electroacoustic efficiency. More than 40% of the electrical power is transmitted in the acoustic beam (compared to less than 1% at best for parametric systems). The large bandwidth (100% of central frequency) allows very short impulse response which makes it possible to use the system in extreme shallow water (less than 5m).
Technology is solid state and does not suffer from bad weather condition as can standard impulsional systems (boomer, sparker).

These two systems exist in 2 and 4 kVA versions. Typical penetrations are 50 to 80m and resolution is 20cm. More than 10 research institutes and survey companies use ECHOES 3500 T3/T1 systems

Echoes 10000: The Ultra-Compact Ultra-High resolution SBP
The Echoes 10000 solution provides the highest resolution available on the market. Its use is optimal for shallow water applications.
Its ultra-large bandwidth makes for effective working in very-shallow water and outperforms non-linear parametric systems.
Typical penetration is 10 to 20m with field-proven resolution of 8cm.

Echoes 5000: Towfish/ROV/AUV full depth SBP
Echoes 5000 is the optimized compact payload for ROV/AUV installation. Its consumption optimization allows more than 75m penetration with 15cm resolution.
Its towfish version fits into the trunk of a car for lake and river survey or fast multi-site management. Echoes 5000 is operational with 5 research institutes today.

Echoes 1500: High Resolution Seismic Towfish SBP for all weather conditions
iXblue develops this unique system to replace boomers and sparkers that cannot be used in adverse weather conditions.

This system allows typical penetration of 150m with resolution of 40cm and can be towed up to 6000m.
One typical use of this system was the anchoring pre-survey carried out at the island of Martinique. The system succeeded in getting high resolution data in volcanic areas with 15 to 20° bottom slope.

DELPH Software
All Echoes products are delivered with Delph Geophysical Software. This unique software suite offers geophysicists state-of-the-art data fusion capability (SSS, SBP, MAG and BATHY). ECHOES SBP data are motion compensated and geolocalized providing real-time processing and display of SBP data.
More than 50 ECHOES SBP are currently in use all over the world. True Flat Spectrum technology provides high quality data combined with a high versatility system for the full SBP range of application.