{
   "Description": "GPS-raw data for reconstructing soil moisture from GNSS-reflectometry at Marquardt",
   
   "Provider": {
      "Name": "Nikolaos Antonoglou",
      "Institution": "GFZ Potsdam",
      "Email": "antonogl@gfz-potsdam.de",
      "Comment": "" 
   },
   
   "SpaceTimeCoverage": {
      "StartDate": "2019-01-01",
      "EndDate": "2022-11-27",
      "RegionName": "Marquardt Cluster (MqC)",
      "BBox": "left: 12.9592, right: 12.9598, bottom: 52.4668, top: 52.4670"
   },

 "Citation": {
      "Info": "These files are part of the dataset published along with the data paper mentioned below.",
      "cite-as": "Heistermann, M., Francke, T., Scheiffele, L., Dimitrova Petrova, K., Budach, C., Schrön, M., Trost, B., Rasche, D.,  Güntner, A.,Döpper, V., Förster, M., Köhli, M., Angermann, L., Antonoglou, N., Zude-Sasse, M. and Oswald, S.: Three years of soil moisture observations by a dense cosmic-ray neutron sensing cluster at an agricultural research site in north-east Germany, Earth Syst. Sci. Data, https://doi.org/10.5194/essd-2023-19, 2023"
    },
   
   "Source": {
      "Name": "GNNS-Reflectometry",
      "Institution": "GFZ Potsdam",
      "Email": "antonogl@gfz-potsdam.de",
      "LinkToOriginalSource": ""
   },

   
   "Units": "dB-Hz",
   
   "SpatialReferenceSystem": {
      "Name": "WGS 84",
      "EPSG": "4326"
   },
 
    "TemporalReferenceSystem": {
      "TimeZone": "UTC",
      "IntervalLength": "5 seconds",
      "TimestampAtEndOfInterval": "False",
      "IntervalAggregation": "instantaneous"
   },
  
   "Further technical details": ["This dataset includes signal-to-noise ratio (SNR) observations from the GNSS receiver (receiver manufacturer: Javad Delta TRE-G3T, antenna: Antcom S67, antenna height: 2.5 m, sensor position: longitude 12.95953, latitude 52.46690) in Marquardt Cluster (MqC).",
      "The directory strcuture is as follows: the data for each year is contained in a seperate zip-archive (2019.zip, ..., 2022.zip). Each zip-archive contains one file for each day of the year (DOY). The naming convention is MARQ{DOY}.{y}: e.g., the observations for January 3, 2020, can be found in the archive 2020.zip in the file MARQ003.20.",
      "Each reading includes SNR measurements of the three GPS carrier signals (i.e. frequencies) for every epoch and satellite (according to availability). The files are separated on a daily basis. Each file has the following columns:",
      "# Satellite: GNSS satellite ID",
      "# Time: record datetime (UTC)",
      "# Elevation: elevation angle of satellite (degrees)",
      "# Azimuth: azimuth angle of satellite (degrees)",
      "# S1: signal-to-noise ratio (SNR) GPS carrier signal L1",
      "# S2: signal-to-noise ratio (SNR) GPS carrier signal L2",
      "# S5: signal-to-noise ratio (SNR) GPS carrier signal L5",
      "The retrieval of SWC in the GNSS-R antenna footprint should follow community conventions. The prime output of such a retrieval will be relative dynamics of soil water content. In order to obtain time series of SWC, these relative dynamics need to be related to local observations of SWC. For that purpose, we recommend the collocated set of continuous TDR measurements at 9 cm depth which are contained in the data subset 'soilmoisture_profiles.zip' with the four location IDs TDR_P1, TDR_P2, TDR_P3, and TDR_P5 the properties of which are represented in the file 'sm_locations.txt' inside 'soilmoisture_profiles.zip'."]
}