Binary Exchange format for GPS/GLONASS/SBAS Data/Metadata/Ephemerides/Orbits/Solutions

Index:
BINEX homepage
current BINEX Record 0x7e outline
current BINEX Record 0x7e Subrecord 0x00

Contact: UNAVCO data guru
Last modified: 20 June 2007

Once the BINEX file or stream has been parsed and a record ID = 0x7e has been identified, the user should consult this page for decoding information of the record 0x7e message. For all 0x7e record messages, the first 1-4 bytes of the message should be examined to determine the subrecord ID. The C/C++ function read_ubnxi() can be used to do this. Once the subrecord ID has been determined, consult the appropriate subrecord description.

• subrecord 0x00

• the time resolution for each time tag is to the millisecond
• the types of valid observables present for the current epoch
• the observables themselves, stored in a variety of pre-specified resolutions

The first byte of the 0x7e-00 message will be the byte 0x00, denoting the subrecord 0x00.

Immediately following the subrecord 0x00 byte with be 6 bytes representing the time tag. The first 4 bytes (uint4) are the number of minutes since 6.0 Jan 1980. The next 2 bytes (uint2) are additional number of milliseconds needed to complete the time tag for the epoch.

Immediately following the 6 time tag bytes will be one or more single bytes (uint1) which specify the types of observables for the current epoch. The highest bit (bit 7) in each of these bytes is reserved, and, if set, indicates that another single byte of observable types is to follow. The last single byte of observable types must have bit 7 = 0. Currently, the defined observables are:

first uint1 for observable types:
• bit 0 = 1: atmospheric pressure
• bit 1 = 1: atmospheric temperature
• bit 2 = 1: atmospheric relative humidity
• bit 3 = 1: wind speed
• bit 4 = 1: wind direction
• bit 5 = 1: rain increment
• bit 6 = 1: hail increment
• bit 7 = 1: read next uint1 for more observable types

second uint1 for observable types:
• bit 0 = 1: atmospheric integrated zenith dry delay
• bit 1 = 1: atmospheric integrated zenith wet (water) delay
• bit 2 = 1: atmospheric integrated zenith total delay
• bit 3 = 1: (reserved)
• bit 4 = 1: (reserved)
• bit 5 = 1: (reserved)
• bit 6 = 1: (reserved)

other uint1 for observable types:
• (reserved)

Next follows the sequentially the data for this epoch, if the corresponding bit above has been set = 1:

• 1-8 bytes (mGFZI) value of 1000xatmospheric pressure in millibars (storing to nearest 0.001 mbar)
• 1-8 bytes (mGFZI) value of 100xatmospheric temperature in °C (storing to nearest 0.01 °C)
• 1-8 bytes (mGFZI) value of 10xatmospheric relative humidity in % (storing to nearest 0.1 %)
• 1-8 bytes (mGFZI) value of 100xwind speed in m/s (storing to nearest 0.01 m/s)
• 1-8 bytes (mGFZI) value of 10xwind directioon in degrees (storing to nearest 0.1°); direction from where the wind blows, and is measured clockwise from geographic north
• 1-8 bytes (mGFZI) value of rain increment in 1/100 mm (storing to nearest 10 µm); accumulation since last scheduled measurement
• 1-8 bytes (mGFZI) value of hail increment in mm (storing to nearest mm); accumulation since last scheduled measurement
• 1-8 bytes (mGFZI) value of 10xatmospheric integrated zenith dry delay in mm (storing to nearest 0.1 mm)
• 1-8 bytes (mGFZI) value of 10xatmospheric integrated zenith wet delay in mm (storing to nearest 0.1 mm)
• 1-8 bytes (mGFZI) value of 10xatmospheric integrated zenith total delay in mm (storing to nearest 0.1 mm)

If the data type bit is not set for a specific observable, then all the associated mGFZI bytes are simply not present in the record at all. For example, if the uint1 byte is set to 0x05, then only data for atmospheric pressure and relative humidity are present.

The BINEX record 0x7e outline for each subrecord on this page should be intepreted as complete and finalized. Since other subrecords may be specified in the future, all other subrecord IDs not explicitly specified on this page are currently reserved.

Last modified Wednesday, 20-Jun-2007 13:48:35 UTC

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