YSI SonTek RiverSurveyor, System Manual

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SonTek/YSI Inc
RiverSurveyor System Manual (May 1, 2007)
15
Section 3. RiverSurveyor Systems, Features, and Considerations
The following topics are covered in Section 3:
•
RiverSurveyor System Types – Outlines the available ADP/RiverSurveyor system types.
•
Doppler Instruments and Current Profiling – What does an ADP do; what data will I see?
•
Bottom-Track – What additional data does bottom-track provide; what are its limitations?
•
Global Positioning Systems (GPS and DGPS) – What additional data does GPS provide?
•
Echo Sounders – What does an echo sounder do; how does it work with RiverSurveyor?
•
Automatic Transducer-Mounting Depth Sensor – Why do I need this sensor?
•
Internal Recorder – How can I use an internal recorder with the RiverSurveyor?
3.1. RiverSurveyor System Types
This section describes the three types of RiverSurveyor systems that are available.
•
RiverSurveyor “Standard” System (
Figure 3-1
)
•
RiverSurveyor “Mini” System (
Figure 3-2
)
•
RiverCat Integrated Catamaran System (
Figure 3-3
)
Each of these systems uses the same software package, and the method of operation is very simi-
lar. All RiverSurveyor systems come with the following features and items.
•
An Acoustic Doppler Profiler
•
Bottom-tracking circuitry enabled
•
Compass/tilt sensor installed
•
A CD-ROM containing the RiverSurveyor software
The Acoustic Doppler Profiler (ADP) is the fundamental part of every RiverSurveyor system.
The ADP is the instrument that collects the water current velocity information.
ADPs are available in different frequencies (
Table 3-1
) for measuring water velocities to varying
depth ranges. The lower the system frequency,
•
the farther the system will measure/profile (i.e., water-track),
•
the farther the system will bottom-track,
•
the farther the distance to the first valid range (depth) cell, and
•
the lower the resolution of the range cell (depth) increments (i.e., larger cell size).
Table 3-1
lists the specifications and available system configurations for each frequency. As an
example of how system frequency affects data collection, consider the following. A 1.5-MHz
ADP can operate to a profiling range (depth) of about 25 m with a minimum resolution (cell
size) of 0.25 m; the first valid data will begin at a range (depth) of about 0.9 m. In comparison, a
3.0-MHz ADP can only operate to a profiling range of about 6 m, but the resolution of the cell
size will be smaller (0.15 m), and the minimum operating depth will be shallower (0.6 m).