Overview
Until now, epipelagic and mesopelagic VM ADCP surveys could not deliver the resolution, precision or range to examine the ocean boundary layer in detail. To study biomass in the upper-ocean boundary layer, you had to add a separate scientific echosounder.
Nortek’s vessel-mounted Signature VM Ocean in the 100 kHz version opens up new opportunities to measure currents and to study biomass simultaneously. The 55 kHz version offers long-range current profiles with a proper precision.
- Currents
- Echosounder
- Bottom track
Highlights
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A coherent and modern system that is quick and convenient to operate
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Automated processing
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VM or stand-alone applications
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A novel transducer design allows focusing on measurement precision (75 kHz) and a 1000 m profiling range (55 kHz)
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Four beams for current profiling with a range over 300 m (100)
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Optional scientific echosounder with multiple modes for biomass (100)
Usage
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Offshore operations
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Internal waves
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Upper-ocean boundary-layer studies (100)
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Detection of krill or plankton in the water column (100)
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Deep-water current profiles, ocean discharge (55)
Setup
The 100 and 55 kHz units are typically mounted inside the hull or in a lowered structure attached to the hull, such as an instrument gondola. Nortek has a mounting guide available.
Deployment
View current velocity data in real time from the VM acquisition software while onboard the vessel. Gather long range current speed and direction information with the 55 kHz unit or use the 100 kHz unit for intermediate profiles and biomass estimates.
Data
Biomass estimates of fish and krill and detections of internal waves with the optional 100 kHz scientific echosounder can be further processed using Echoview software. Process and export current data subsets of interest using the VM review software once your survey has ended.
Profiling range** | 300-400 m |
Doppler processing | Broadband & Narrowband |
Cell size | 3-15 m |
Max no. cells | 200 |
Min. blanking | 2 |
Minimum accuracy | 1.0% of the measured value ± 0.5 cm/s |
Velocity resolution | 0.1 cm/s |
Maximum sampling rate | 1 Hz (1/3 Hz with BT and echosounder) |
Velocity range (along beam) | 5 m/s |
No. of beams | 4 slanted at 20° |
**) Depending on acoustic scattering condition. |
Profiling range** | 685/1000 m |
Doppler processing | Broadband/Broadband & Narrowband |
Cell size | 6-20 m |
Max no. cells | 200 |
Min. blanking | 2 |
Minimum accuracy | 1.0% of the measured value ± 0.5 cm/s |
Velocity resolution | 0.1 cm/s |
Maximum sampling rate | 1 Hz (1/3 Hz at max power) |
Velocity range (along beam) | 5 m/s |
No. of beams | 3 slanted at 20° |
**) Depending on acoustic scattering condition. |
Single ping std @ 3 m/s | TBA |
Long-term accuracy | TBA |
Minimum altitude | 5 m |
Maximum altitude | 560 m |
Velocity resolution | 0.01 mm/s |
Maximum sampling rate | 1 Hz (1/3 Hz with VP and echosounder) |
Single ping std @ 3 m/s | TBA |
Long-term accuracy | TBA |
Minimum altitude | 50 m |
Maximum altitude | 1200 m |
Velocity resolution | 0.01 mm/s |
Maximum sampling rate | 1 Hz |
Sampling | Same as velocity for slanted beams |
Resolution/dynamic range | 0.5 dB/70 dB |
Dynamic range | 70 dB slanted beams |
Transducer acoustic frequency | 100 kHz |
No. of beams | 4 slanted at 20° |
Beam width | 6.1° |
Sampling | Same as velocity |
Resolution/dynamic range | 0.5 dB/70 dB |
Dynamic range | 70 dB slanted beams |
Transducer acoustic frequency | 75 and 55 kHz |
No. of beams | 3 slanted at 20° |
Beam width | 4.5°-5.5° |
No. of beams | 1 vertical |
Transducer acoustic frequency | 70-120 kHz |
Sampling | 1 Hz (1/3 Hz with VP and BT) |
Transducer beam width | 15° @ 70 kHz, 8.7° @ 120 kHz |
Resolution | 0.375 –4 m |
Resolution/ dynamic range | 0.01 dB/130 dB |
Transmit pulse | Monochromatic 70 kHz, 90 kHz and 120 kHz or frequency chirp (90 kHz, 50% BW) |
Transmit power | 7.5-120 W adjustable |
Chirp signal processing | Pulse compression or binned frequency response |
No. of beams | N/A |
Transducer acoustic frequency | N/A |
Sampling | N/A |
Transducer beam width | N/A |
Resolution | N/A |
Resolution/ dynamic range | N/A |
Transmit pulse | N/A |
Transmit power | N/A |
Chirp signal processing | N/A |
Temperature sensor range / accuracy | -4 °C to 40 °C / 0.1 °C |
Pressure | Piezo resistive |
Standard range | 0-1500 m (inquire for options) |
Accuracy/precision | 0.1% FS / Better than 0.002% of full scale |
Compass and tilt | Solid-state magnetometer and accelerometer |
Data recording | 16 GB (inquire for options) |
Data cable | 30 m Ethernet cable (inquire for options) |
IO | Ethernet |
DC input | 15-48 V DC |
Temperature sensor range / accuracy | -4 °C to 40 °C / 0.1 °C |
Pressure | Piezo resistive |
Standard range | 0-1500 m (inquire for options) |
Accuracy/precision | 0.1% FS / Better than 0.002% of full scale |
Compass and tilt | Solid-state magnetometer and accelerometer |
Data recording | 16 GB (inquire for options) |
Data cable | 30 m Ethernet cable (inquire for options) |
IO | Ethernet |
DC input | 48 V DC |
Maximum diameter | 460 mm |
Maximum length without room for internal batteries | 350 mm |
Maximum diameter | 650 mm |
Maximum length without room for internal batteries | 314 mm |
Operating temperature | -4 °C to 40 °C |
Storage temperature | -20 °C to 60 °C |
Vibration | IEC 60068-1/IEC60068-2-64 |
EMC approval | IEC 61000 |
Depth rating | 1500 m – Bottom track is limited to surface vessels |
Connectors | Straight fitted MCBH6F (Ethernet) |
Housing | Small instrument housing |
Material | POM with titanium fasteners |
Processor/memory | Intel i5/8 GB |
Hard disk | SSD, 500 GB |
Operating system | Windows® 10 |
Housing | Half 19" 2 HE case or 19" rack-mountable 1 HE |
Dimensions | 265x110x340 mm or 480x45x325 mm |
Input | 24 V DC, 20 W typical |
Total weight | 5.75 or 3.80 kg |
Connections | Power, Signature ADCP, AN_GNSS, 2x HDMI, 2xLAN, 3x USB, 1x RS-232 (optional) |
Acquisition | Signature VM - binary, GNSS compass - binary |
Timing | < 0.6 s, IEEE1588/PTP for absolute time stamping (GNSS/Signature VM) |
Configuration | Signature VM (partly) GNSS Advanced navigation |
Display | Vessel track in map, Bottom-track velocity, Bottom-track depth, Velocity magnitude and direction, Echo amplitude (slanted beams), Echo correlation (slanted beams), corrected relative volume backscatter (100) |
Status | Signature VM + AN_GNSS compass |
Output | NMEA data strings online CSV, ASCII VMT, MATLAB VMT, MATLAB, KML |
Accelerometer dynamic | ± 2 g |
Gyro dynamic range | ± 250°/sec |
Magnetometer dynamic range | ± 1.3 Gauss |
Pitch and roll range/resolution | ± 90° (pitch), ± 180° (roll)/0.01° |
Pitch and roll accuracy | ± 2° (dynamic)3), ± 0.5° (static, ± 30°) |
Heading range / resolution | 360°, all axes/0.01° |
Heading accuracy | ± 3° (dynamic)3), ± 2° (static, tilt < 20°) |
Sampling rate | Same as measurement rate |
Signature100 VM Ocean
Signature55 VM Ocean
4-beam head (100)
3 beam head (55)
5-beam head (adds 95 kHz center transducer for echo sounder)(100)
Short, no room for battery (external battery canister for bottom-mount use) (same as currently stated; same for 100 and 55)
16 GB SD card data logger (same as currently stated; same for 100 and 55)
64 GB SD card data logger (same as currently stated; same for 100 and 55)
128 GB SD card data logger (same as currently stated; same for 100 and 55)
Pressure sensor, 0-1500 m, accuracy 0,1% of FS (standard) (same as currently stated; same for 100 and 55)
Pressure sensor, 0-100 m, accuracy 0,1% of FS (same as currently stated; same for 100 and 55)
AD2CP: 30 m Ethernet cable with MCIL6MP, Power/RJ45 at dry end (standard) (same as currently stated; same for 100 and 55)
AD2CP: 30-100 m Ethernet cable (specify length) with MCIL6MP-PWR/RJ45 (same as currently stated; same for 100 and 55)
Vessel-mounted over the side (same as currently stated; same for 100 and 55)
Vessel hull-mounted (same as currently stated; same for 100 and 55)
Unmanned Surface Vehicle (USV) mounted (please inquire) (same as currently stated; same for 100 and 55)
Compass and tilt sensor
AHRS
Heading GNSS (dGNSS),
High Accuracy Heading GNSS (RTK)

Battery canister, aluminium for 36*D pack w/cable to Signature 2-pin Inline (500m rating)

Battery canister, aluminium for 2*36*D pack w/cable to Signature 2-pin Inline (500m rating)

Battery, 18 V - 540 Wh, alkaline
The standard battery for instruments in the Signature series.

Battery, 19 V - 1800 Wh, lithium
An optional high-capacity lithium battery for instruments in the Signature series.

Battery pack, 5-pack, 18 V - 540 Wh, alkaline
The standard battery for instruments in the Signature series.

Battery pack, 10-pack, 18 V - 540 Wh, alkaline
The standard battery for instruments in the Signature series.