Klein Marine Systems, Inc. HydroChart 5000, Operation And Maintenance Manual

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Technical Description
1-5
1.5 Technical Description
The HydroChart 5000 Sonar System is a multiple swath forming, frequency
modulated (FM) chirp side looking sonar that provides high speed, high resolution,
extended range imagery and bathymetry. The two primary drawbacks of
conventional side-looking sonars, along-track resolution and towing speed
limitation, have been addressed by simultaneously forming multiple dynamically
focused beams per side, per ping. This allows greater side scan survey speeds
without the usual loss of bottom coverage while maintaining high resolution. In
addition, the formed swaths are focused dynamically with across-track range,
thereby offering an inherently improved along-track resolution over unfocused
systems. The interferometric bathymetry (also referred to as Phase Differencing)
component of the HydroChart 5000 Sonar System is not a multibeam sonar and
requires that speed and range settings be considered when operating the system for
100% bottom coverage.
1.5.1 Sonar Head Unit
The Sonar Head Unit consists of the sonar arrays together with the sonar
electronics in a lightweight frame assembly. The sonar electronics, which is
contained inside a waterproof housing, includes transmitters, receivers and digital
circuits that combine time-synchronized complex stave samples, ping trigger
timing and optional time-synchronized motion data from the vessel’s sensors. An
altimeter is included, and the system accommodates an optional sound velocity
sensor or a CTD. For hull mount configurations, the electronics bottle is located
inside the vessel’s hull, and an optional transducer mounting bracket is required.
The two transducer arrays are each composed of 12 piezoelectric ceramic
Figure 1-2:
HydroChart 5000 Sonar System Sonar Head Unit