Accelerometer Sensor Raw

The accelerometer buffer sends back bins of 31 voltages for each measurement. These bins correspond to frequencies. Hence the voltages here are multidimensional in terms of time and frequency. However, the data products of the accelerometer are significant_wave_height and dominant_wave_period, and these have just a single value for each of the 31 voltages. Hence the realtime products are simple datasets with where only the time has dimension larger than 1. As an example below, the sensor-raw NetCDF file from B0104 is shown.


netcdf B0104.accelerometer.sensor-raw {
dimensions:
	lon = 1 ;
	lat = 1 ;
	depth = 1 ;
	freq = 31 ;
	time = UNLIMITED ; // (570 currently)
variables:
	double lat(lat) ;
		lat:long_name = "Latitude" ;
		lat:short_name = "lat" ;
		lat:units = "degrees_north" ;
		lat:scale_factor = 1. ;
		lat:add_offset = 0. ;
		lat:_FillValue = -999. ;
		lat:valid_range = -90., 90. ;
		lat:Comment = "Coordinate variable" ;
		lat:epic_code = 500 ;
		lat:standard_name = "latitude" ;
	double lon(lon) ;
		lon:long_name = "Longitude" ;
		lon:short_name = "lon" ;
		lon:modulo = 360. ;
		lon:units = "degrees_east" ;
		lon:scale_factor = 1. ;
		lon:add_offset = 0. ;
		lon:_FillValue = -999. ;
		lon:valid_range = -180., 180. ;
		lon:epic_code = 502 ;
		lon:Comment = "Coordinate variable" ;
		lon:standard_name = "longitude" ;
	double depth(depth) ;
		depth:long_name = "Depth" ;
		depth:standard_name = "depth" ;
		depth:short_name = "D" ;
		depth:units = "meters" ;
		depth:positive = "down" ;
		depth:scale_factor = 1. ;
		depth:add_offset = 0. ;
		depth:_FillValue = -999. ;
		depth:valid_range = -10000., 100. ;
		depth:epic_code = 3 ;
		depth:Comment = "Coordinate variable" ;
	double freq(freq) ;
		freq:long_name = "Frequency" ;
		freq:short_name = "D" ;
		freq:units = "hertz" ;
		freq:scale_factor = 1. ;
		freq:add_offset = 0. ;
		freq:_FillValue = -999. ;
		freq:valid_range = 0., 32. ;
		freq:Comment = "Coordinate variable" ;
	double time(time) ;
		time:long_name = "Time" ;
		time:standard_name = "time" ;
		time:short_name = "time" ;
		time:units = "days since -4713-01-01 00:00:00" ;
		time:scale_factor = 1. ;
		time:add_offset = 0. ;
		time:_FillValue = -999. ;
		time:valid_range = 0., 2460000. ;
		time:epic_code = 624 ;
		time:Comment = "Coordinate variable" ;
	float volts(time, freq, depth, lat, lon) ;
		volts:long_name = "Volts" ;
		volts:short_name = "V" ;
		volts:scale_factor = 1. ;
		volts:add_offset = 0. ;
		volts:_FillValue = -999.f ;
		volts:units = "m" ;
		volts:valid_range = 0.f, 1000.f ;
		volts:is_dead = 0 ;
		volts:sensor_depth = 0. ;

// global attributes:
		:title = "Gulf of Maine Ocean Observing System: Realtime Buoy Observations" ;
		:institution = "Department of Physical Oceanography, School of Marine Sciences, University of Maine" ;
		:institution_url = "http://gyre.umeoce.maine.edu" ;
		:history = "" ;
		:source = "realtime buoy observation" ;
		:references = "http://gyre.umeoce.maine.edu/data/gomoos/doc/buoy_system_doc/buoy_system/book1.html" ;
		:comment = "processed with MATLAB" ;
		:latitude = 43.180439 ;
		:longitude = -70.427548 ;
		:Conventions = "CF-1.0" ;
		:project = "GOMOOS" ;
		:project_url = "http://gomoos.org" ;
		:contact = "nealp@maine.edu,ljm@umeoce.maine.edu,jevans@umeoce.maine.edu" ;
		:time_zone = "UTC" ;
		:julian_day_convention = "Julian date convention starts at 00:00:00 UTC on 1 January 4713 BC" ;
		:buffer_type = "accelerometer" ;
		:instrument_number = 0 ;
		:processing = "sensor-raw" ;
		:water_depth = 62. ;
		:mooring_site_id = "B0104" ;
		:mooring_site_desc = "Western Maine Shelf" ;
		:breakout_id = 7 ;
		:delta_t = 60 ;
		:magnetic_variation = -16. ;
		:last_mysql_update_index = -1 ;
		:starting_julian_day_number = 2452755.95833333 ;
		:starting_julian_day_string = "2003-4-25 23:00:00" ;
		:ending_julian_day_number = 2452779.67152778 ;
		:ending_julian_day_string = "2003-5-19 16:07:00" ;
data:

 lat = 43.180439 ;

 lon = -70.427548 ;

 depth = 0 ;

 freq = 0.03125, 0.0625, 0.09375, 0.125, 0.15625, 0.1875, 0.21875, 0.25, 
    0.28125, 0.3125, 0.34375, 0.375, 0.40625, 0.4375, 0.46875, 0.5, 0.53125, 
    0.5625, 0.59375, 0.625, 0.65625, 0.6875, 0.71875, 0.75, 0.78125, 0.8125, 
    0.84375, 0.875, 0.90625, 0.9375, 0.96875 ;
}