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RDI ADCP Ensemble-Averaged Time Series

15-minute ensemble-averaged data files forTeledyne RDI ADCPs are described here. Ancillary data (e.g., temperature, pitch, roll) are also available independently.

Revision History

  • 20111121: Initial product released

Formats

This data is available in MAT format. The filename is appended with '-ENSEMBLE' to differentiate it from the MAT format with the complete time-series. Content descriptions and example files are provided below.

MAT

MAT files (v7) can be opened using MathWorks MATLAB 7.0 or later. To produce the file, the following requirements apply:

  • A new file is started at the beginning of each day or when the driver is restarted (this should account for configuration changes, site changes, etc).
  • Only records with valid checksums are included.
  • The instrument date/time field is replaced using the NEPTUNE timestamp at the beginning of the log file (since this timestamp is more accurate than the instrument clock)
  • A correlation threshold of 64 and an error velocity threshold of 2 m/s are used to screen the data. Within each bin, only the pings that are within those thresholds are used in the ensemble-averaging. If there were no good pings, the velocity is NaN.

The file contains four structures: meta, adcp, config, and units.

meta: structure containing the following metadata fields.

  • deviceID: A unique identifier to represent the instrument within the NEPTUNE  Canada network.
  •  creationDate:Date and time (using ISO8601 format) that the data product was produced.  This is a valuable indicator for comparing to other revisions of the  same data product.
  • deviceName: A name given to the instrument.
  • deviceCode: A unique string for the instrument which is used to generate data  product filenames.
  • lat: Obtained at time of deployment.
  • lon: Obtained at time of deployment.
  • depth: Obtained at time of deployment.
  • deviceHeading: Obtained at time of deployment (exception: for Device ID 13051, this field is NaN since this ADCP is on a mooring and does not have a fix heading).
  • siteName: Name corresponding to its latitude, longitude, depth position.
  • locationName: The node of the NEPTUNE Canada observatory. Each location contains many sites.
  • samplingPeriod: Sampling rate of the instrument in seconds.
  • searchID: Identifier for data search query.
  • dataProductVer: Version of data product.

adcp: structure containing the ADCP data, having the following fields.

  • time: vector, timestamp in datenum format (obtained from time the reading reached the shore station)
  • range: vector of distance to each bin
  • ens: vector, ensemble number
  • u: 2D matrix, East velocity relative to True North
  • v: 2D matrix, North velocity relative to True North
  • w: 2D matrix, Upward Velocity
  • velocityError: 2D matrix, computed using RDI algorithm
  • pingsPerEnsemble: 2D matrix, number of pings used in each bin to obtain 15-minute average (an indicator of pings which passed both the correlation or error velocity tests).
  • compassHeading: vector, magnetic compass heading time-series
  • pitch: vector, pitch time-series
  • roll: vector, roll time-series
  • temperature: vector, temperature time-series
  • pressure: vector, pressure time-series
  • depth: vector, calculated from range and deployment depth

config: structure containing ADCP configuration details, where some field names are appended with '_XX' to represent the corresponding configuration command (beneficial for experienced RDI ADCP users).

  • fwVer: CPU firmware version
  • fwRev: CPU firmware revision
  • sysCfg: hardware configuration definition
  • freq: frequency
  • beamPattern: convex or concave
  • orient: orientation (e.g.,'Up' indicates transducers are looking upward)
  • beamAngle: beam angle
  • janusCfg: description of Janus Configuration
  • lagLength: time period between sound pulses
  • nbeams: number of beams
  • nbins_WN: number of bins
  • npings_WP: number of pings per ensemble
  • cellSize_WS: length per cell
  • profilingMode: sigal processing mode
  • corrThresh_WC: correlation threshold
  • codeReps: code repetitions in transmit pulse
  • percentGoodMin_WG: percent good threshold
  • errVelThreshold_WE: error velocity threshold
  • timePing_TP: time between pings within ensemble
  • coord_EX: coordinate transformation processing parameters
  • coordSys: coordinate system (evaluated from coord_EX)
  • headingAlign_EA: correction factor for physical heading misalignment
  • headingBias_EB: correction factor for electrical/magnetic heading bias
  • sensorSrc_EZ: defines selected source of environmental sensor data
  • sensorAvail: defines available sources of environmental sensor data
  • bin1Dist: distance to the middle of the first depth cell
  • transmitLength_WT: length of the transmit pulse
  • falseTrgt_WA: false target threshold
  • transmitLagDistance: distance between pulse repetitions
  • cpuSN: CPU board SN
  • sysBndwdth_WB: bandwidth setting (narrow or wide)
  • sysPower_CQ: system power setting
  • instSN: instrument serial number
  • ensInterval: ensemble interval
  • ambiguityVelocity_WV: radial ambiguity velocity

units: structure containing unit of measure for fields in structures above. For instance, units.pressure='decibar'.

For details about the configuration parameters, refer to the manufacturer documentation (especially the WorkHorse Commands and Output Data Format manual).

Example: RDIADCP75WH3808_20111016T000001Z-ENSEMBLE.mat

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