The proposed below Binary Receiver Independent Exchange format has the same basic philosophy as RINEX-2 one, however three following modifications are suggested:

• Both instrumentation data blocks: Receiver-Ranging Measurements and Broadcast Ephemerides, may be stored when available (i.e. sorted according to a reception time) in the same file.
  
  
• Channel's number must be assigned to each tracked satellite. It is required by channel dependent correction algorithms and for monitoring of a receiver's reliability.
  
  
• Signal/Noise ratio is not scaled but it is rounded to the nearest integer value.

1. FLAG 1: Version (1 byte)
Binary exchange format version.

2. FLAG 2: Spare (1 byte)

3. FILE-HEADER (as in RINEX-2, variable length)
In order to make available variable length of the section, the RINEX-2 format for the header lines is adopted. The header is composed of a number of maximum 80 characters long strings (vectors) terminated with CR-character. The last line must contain the character sequence: >>END OF HEADER<<
Any change of header information must be reported by inserting appropriate header lines into the data file. These >>updating-lines<< must follow the Event Flag >>header information follows<< (similary as in original RINEX).
The file-header must contain the following information (the keywords as in RINEX):

• Decoding and Converting programs information:
• Marker name
• Marker number
• Name of observer, agency
• Receiver information
• Antenna information
• Marker XYZ coordinates
• Marker antenna offset
• Wavelength factors
• Observer name, agency
• Number of observation types and observation types (2-characters IDs)
• Data sampling rate (seconds)
• Number and sequence of SNR-observations (This is new)
• Comments

4. EPOCH-HEADER (Structure, 12 bytes)

	Time tag                                    long int, 4 bytes
	Floating part of the time tag               long int, 4 bytes
	Receiver clock offset (fraction of second)  long int, 4 bytes

		typedef struct {
		  long int	timeTag,
				partOfSec,
				clfOffset;
		} EPOCH_HEADER;

5. NUMBER OF SATELLITES in the current epoch of event flag (1 byte)
Value greater than 0 means: number of observations in the current epoch, otherwise event flag. Event flags according to the RINEX-2.

6. SATELLITE IDs (Variable length = number of satellites tracked)
Vector of bytes containing SV PRN ID:

  bit 7 (MSB)  - AS flag (1-on, 0-off)
  bits 0 - 6   - SV PR Number

7. CHANNEL NUMBERS (Variable length = number of satellites tracked)
Vector of unsigned character bytes containing receiver channel numbers, where:

  bit 7 (MSB)  - Loss of lock indicator
  bits 0 - 6   - Channel number

8. SIGNAL/NOISE COUNTS (Variable length = number of satellites tracked * Number of SNR-observations)
Vector of 2 bytes words with L1 S/N counts.
    Length = Number of satellites * 2 bytes * Number of frequencies;
String of 2 bytes words with L2 S/N counts (Only for double frequency receivers).
    Length = Number of satellites * 2 bytes * Number of frequencies;

9. SINGLE OBSERVATION (10 bytes)

	Value			double (8 bytes)
	Observation type	char. (1 byte)
	System ID 		unsigned char. (1 byte)
	         Bit 0 bis 2: system's ID; bits 3 bis 7: spare for a quality indicator

		typedef struct {
		  double	Value;
		} singleObservation;

• L1, L2, C1, C2 (cycles)
• P1, P2 (meters)
• D1, D2, TT

• GPS - 0
• GLONASS - 1
• GNSS-2 - 2

10. BROADCAST EPHEMERIS

	Week Number and GPS seconds since
	Jan. 6, 1980 (transmission time)		long integer  seconds
	Code(s) on L2 Channel				unsigned char N/A
	L2 P data flag					unsigned char N/A
	SV Accuracy					unsigned char (as in ICD-2000)
	SV Health					unsigned char N/A
	Age of Data Clock, AODC				long integer  seconds
	L1-L2 correction, TGD				double        seconds
	Age of Data Ephemeris, AODE			long integer  seconds
	Clock correction:
		toc					integer       seconds
		af0					double        seconds
		af1					double        sec./sec.
		af2					double        sec./sec.^2
	Mean anomaly at reference time, M0		double        radians
	Mean motion, Dn					double        rad./sec.
	Eccentricity, e					double        N/A
	Square root of the semi-major axis, sq.A	double        1/m^2
	Right ascension at reference time, OMEGA0	double        radians
	Inclination angle at reference time, i0		double        radians
	Argument of perigee, omega			double        radians
	Rate of right ascension, OMEGADOT		double        rad./sec.
	Rate of inclination angle, IDOT			double        rad./sec.
	Amplitudes of the cos. Harmonic correction term to the:
		argument of latitude Cuc		double        radians
		orbit radius         Crc		double        meters
		angle of inclination Cic		double        radians
	Amplitudes of the cos. Harmonic correction term to the:
		argument of latitude Cus		double        radians
		orbit radius         Crs		double        meters
		angle of inclination Cis		double        radians
	Reference time ephemeris, toe			integer       seconds

Last modified Friday, 21-Jul-2006 23:21:07 UTC

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