PDS_VERSION_ID      = PDS3                                                    
RECORD_TYPE         = FIXED_LENGTH                                            
RECORD_BYTES        = 80                                                      
OBJECT              = TEXT                                                    
  PUBLICATION_DATE    = 1996-08-15                                            
  NOTE                = "DSN Orbit Data File Software Interface               
                         Specification."                                      
END_OBJECT          = TEXT                                                    
END                                                                           
                                                                              
MGSO System Requirements                                                      
Detailed Interface Design                                                     
                                                                              
SFOC-NAV-TRK-2-18                                                             
                                                                              
MGSO Tracking System Interfaces                                               
Orbit Data File Interface                                                     
Mark IVA                                                                      
                                                                              
Initial Release Date: June 15, 1983                                           
Reissued August 15, 1996                                                      
                                                                              
Prepared by;                                                                  
G. L. goltz                                                                   
RMDC Software CDE                                                             
                                                                              
Accepted by:                                                                  
J. E. Ekelund                                                                 
Navigation Software CDE                                                       
                                                                              
Approved by:                                                                  
V. N. Legerton                                                                
Navigation System Engineer                                                    
                                                                              
Released by:                                                                  
G. Dawson                                                                     
MGSO Document Release                                                         
                                                                              
                                                                              
Change Log                                                                    
                                                                              
Change Number      Date      Affected Pages                                   
                                                                              
Original issue     6/15/82     All                                            
Change 1           8/15/96     All (Document Reformatted)                     
                                                                              
                      Contents                                                
Section                                           Page                        
1 Introduction                           1-1                                  
1.1     Purpose and Scope                         1-1                         
1.2     Revision and Control                      1-1                         
                                                                              
2       General Information                       2-1                         
                                                                              
3       Data Format and Fields                    3-1                         
3.1     GCF Data Blocks                           3-1                         
3.2     Electronic and Magnetic Tape Interface    3-2                         
                                                                              
                      Figures                                                 
Figure                                             Page                       
2-1     Data Flow for Orbit Data File Interface    2-2                        
                                                                              
                      Tables                                                  
Table                                              Page                       
3-1a    ODF File Label Group Header Format         3-3                        
3-1b    ODF File Label Group Data Format           3-3                        
3-2a    ODF Identifier Group Header Format         3-4                        
3-2b    ODF Identifier Group Data Format           3-4                        
3-3a    ODF Orbit Data Group Header Format         3-5                        
3-3b    ODF Orbit Data Group Data Format           3-5                        
3-4a    ODF Ramp Groups Header Format              3-8                        
3-4b    ODF Ramp Groups Data Format                3-8                        
3-5a    ODF Clock Offsets Group Header Format      3-9                        
3-5b    ODF Clock Offsets Group Data Format        3-9                        
3-6a    ODF Uplink Phase Group Header Format       3-10                       
3-6b    ODF Uplink Phase Group Data Format         3-10                       
3-7a    ODF Data Summary Group Header Format       3-11                       
3-7b    ODF Data Summary Group Header Format       3-11                       
3-7     ODF End-of-File Group Format               3-11                       
                                                                              
                     Appendices                                               
Appendix                                           Page                       
A       Doppler and Range Observables              A-1                        
                                                                              
______________________________________________________________________________
Section 1                                                                     
Introduction                                                                  
                                                                              
1.1 Purpose and Scope                                                         
                                                                              
This module specifies the Orbit Data File (ODF) format of the radio metric    
data from the Deep Space Network (DSN). The content and formats of the ODF    
data blocks generated by the Network Operations Control Center (NOCC)         
Navigation Subsystem (NAV), and either transmitted electronically or provided 
on magnetic tape by the NAV are herein defined.                               
                                                                              
1.2 Revision and Control                                                      
 Revisions or changes to information herein presented may be initiated in     
accordance with the procedures in Section 1 of this document.                 
                                                                              
________________________________ end page 1-1 ________________________________
                                                                              
Section 2                                                                     
General Information                                                           
                                                                              
The data will be stored by the NOCC NAV for transmission.                     
                                                                              
Figure 2-1 shows the data flow from the DSN Signal Processing Center (SPC) to 
the Remote Mission Operations Center (RMOC) for the transmitted data, and for 
data provided electronically or on magnetic tape to JPL Projects.             
                                                                              
When the ODFs are to be transmitted to an RMOC, the Ground Communications     
Facility (GCF) is assumed to be transparent. The data shall be formatted into 
1200-bit or 4800-bit data blocks and transmitted to the user via the Digital  
Communications Subsystem (GDC) of the GCF.                                    
                                                                              
________________________________ end page 2-1 ________________________________
                                                                              
                                                                              
                                                                              
  -----------                       ----------------            ------------  
 | DSCC      | TRK-2-15A/2-20/2-30 | Ground         | TRK-2-18 | Remote     | 
 | Tracking  | ------------------->| Communications | -------->| Mission    | 
 | Systems   |                     | Facility       |          | Operations | 
  -----------                       ----------------           | Center     | 
                                     |      |    ^              ------------  
         TRK-2-15A/2-20/2-30         |      |    |                            
         -----------------------------      |    |                            
        |                        TRK-2-15A/ |    | TRK-2-18                   
        |                        2-20/2-30  |    | (file transfer)            
        |                       (primary-   |    |                            
        |                        real-time) |    |                            
        v                                   v    |                            
  -----------                       ----------------                          
 | Central   |                     | NOCC           |                         
 | Data      | ------------------->| Navigation     | --------                
 | Recorder  |                     | Subsystem      |         | TRK-2-18      
  -----------                       ----------------          | (backup,      
                                         |                    | tape transfer)
                                         |                    v               
                                         |  TRK-2-18       ----------         
                                         | (file transfer)| JPL      |        
                                         ---------------->| Projects |        
                                                           ----------         
                                                                              
Figure 2-1.  Data flow for Orbit Data File interface                          
                                                                              
________________________________ end page 2-2 ________________________________
                                                                              
Section 3                                                                     
Data Format and Fields                                                        
                                                                              
3.1 GCF Data Blocks                                                           
                                                                              
The ODF data blocks are standard 1200-bit or 4800-bit data blocks that contain
radio metric data that have been reformatted from the 820-13, TRK-2-15A,      
TRK-2-20, or TRK-2-30 formats. The first 120 bits of the block form the block 
header and provide information common to all data in the block.  The Block    
Information Field (BIF) consists of 1032 bits for a 1200-bit block and        
contains three packets (each consisting of nine 32-bit words) described in    
Tables 3-1 through 3-7.  The BIF for the 4800-bit block consists of 4632 bits 
and contains 16 packets of data.  The last 48 bits of the data block contain  
the GCF error detection and correction data, the Error Status Code (ESC) and  
the Error Polynomial Code (EPC).  The ODF blocks will be ordered by block     
header time and date. Detailed descriptions of the header, BIF, and block     
ending are provided in the following paragraphs:                              
                                                                              
WORD 1 THRU WORD 8, BIT 8                                                     
                                                                              
Standard DSN Block Header as described in module OPS-6-8 of this document,    
with the following code assignments:                                          
                                                                              
Source Code = AF16  (DSN NAV)                                                 
                                                                              
UDT Code = 1516  (0258)                                                       
                                                                              
DDT Code = 1416  (0248)                                                       
                                                                              
WORD 8, BITS 9 THRU 16                                                        
                                                                              
Set to zeros                                                                  
                                                                              
WORD 9 THRU WORD 72/WORD 297                                                  
                                                                              
BIF - ODF data with the following constraints:                                
                                                                              
 (1) Each complete ODF will span several blocks.                              
                                                                              
 (2) A complete ODF will consist of the following data presented in order of  
     transmission:                                                            
                                                                              
  a) File Label group - one per ODF (Tables 3-la and 3-lb);  required         
                                                                              
  b) Identifier group - one per ODF (Tables 3-2a and 3-2b);  required         
                                                                              
  c) Orbit Data group - multiple records, time ordered (Tables 3-3a and 3-3b);
     required                                                                 
                                                                              
  d) Ramp groups - one group for each DSS, multiple records, time ordered     
     (Tables 3-4a and 3-4b);  optional                                        
                                                                              
  e) Clock Offsets group - multiple records, time ordered (Tables 3-5a and    
     3-5b);  optional                                                         
                                                                              
  f) Data Summary group - multiple records, ordered by station, band, and data
     type (Tables 3-6a and 3-6b);  optional                                   
                                                                              
_________________________________ end page 3-1 _______________________________
                                                                              
  g) End-of-File group - one per ODF (Table 3-7);  required                   
                                                                              
 (3) Each ODF consists of the radio metric data for one spacecraft, zero or   
     more quasars, and one or more stations.                                  
                                                                              
 (4) Character data are 8-bit ASCII-equivalent integer values.                
                                                                              
 (5) Times, except as noted, are given as seconds past zero hours UTC, of     
     January 1, 1950.                                                         
                                                                              
 (6) For 1200-bit blocks, Words 63 through 72 will always contain filler      
     (repetitive 10002). For 4800-bit blocks, Word 297 will always contain    
     filler. Unused portions of any BIF will contain filler.                  
                                                                              
 (7) The ODF data words are 32 bits in length.                                
                                                                              
 (8) The 5th and 6th data words of an ODF packet/record are always zero (0)   
     for a group header record, and are always non-zero for a data record.    
                                                                              
 (9) The parameter field pack format conventions used herein are as follows:  
                                                                              
     Ix = unsigned integer, x bits in length                                  
     Sx = signed integer, x bits in length, two's complement                  
                                                                              
 (10) Most data parameters will be provided as binary integers;               
      two's complement will be used for all fields that may have negative     
      values.                                                                 
                                                                              
 (11) Single-bit status parameters will be set to one (1) for no, bad, off,   
      out of tolerance, etc.; and will be set to zero (0) for yes, good, on,  
      in tolerance, etc.                                                      
                                                                              
WORD 73 THRU WORD 75/WORD 298 THRU WORD 300                                   
                                                                              
 Standard DSN block ending as described in module OPS-6-8 of this document.   
                                                                              
                                                                              
                                                                              
3.2 Electronic and Magnetic Tape Interface                                    
                                                                              
The ODF data are provided in a disk files or on unlabeled, 9-track,           
1600-bits/ in. magnetic tapes. Each ODF block (or physical record)            
consists of 2016 32-bit words, for a total length of 64,512 bits. Each block  
contains 224 9-word (288-bit) logical records. These records are described    
in Tables 3-1 through 3-8.                                                    
                                                                              
_________________________________ end page 3-2 _______________________________
                                                                              
                                                                              
                Table 3-1a.  ODF File Label Group Header Format               
|====================================================================|        
| Item  |  Pack   |  Data |        Description                       |        
|Number |  Format |  Word |                                          |        
|-------+---------+-------+------------------------------------------|        
|   1   |   S32   |    1  | Primary Key = 101                        |        
|   2   |   I32   |    2  | Secondary Key = 0                        |        
|   3   |   I32   |    3  | Logical Record Length (in packets) = 1   |        
|   4   |   I32   |    4  | Group Start Packet Number (=0)           |        
|  5-9  |   I32   |   5-9 | 0                                        |        
|====================================================================|        
                                                                              
                Table 3-1a. ODF File Label Group Header Format                
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |   I8   |   1  | 1st ASCII "Character" of System ID       |          
|   2   |   I8   |      | 2nd ASCII "Character" of System ID       |          
|   3   |   I8   |      | 3rd ASCII "Character" of System ID       |          
|   4   |   I8   |      | 4th ASCII "Character" of System ID       |          
|   5   |   I8   |   2  | 5th ASCII "Character" of System ID       |          
|   6   |   I8   |      | 6th ASCII "Character" of System ID       |          
|   7   |   I8   |      | 7th ASCII "Character" of System ID       |          
|   8   |   I8   |      | 8th ASCII "Character" of System ID       |          
|   9   |   I8   |   3  | 1st ASCII "Character" of Program ID      |          
|  10   |   I8   |      | 2nd ASCII "Character" of Program ID      |          
|  11   |   I8   |      | 3rd ASCII "Character" of Program ID      |          
|  12   |   I8   |      | 4th ASCII "Character" of Program ID      |          
|  13   |   I8   |   4  | 5th ASCII "Character" of Program ID      |          
|  14   |   I8   |      | 6th ASCII "Character" of Program ID      |          
|  15   |   I8   |      | 7th ASCII "Character" of Program ID      |          
|  16   |   I8   |      | 8th ASCII "Character" of Program ID      |          
|  17   |  I32   |   5  | Spacecraft ID Number                     |          
|  18   |  I32   |   6  | File Creation Time (YYMMDD)              |          
|==================================================================|          
                                                                              
_________________________________ end page 3-3 _______________________________
                                                                              
          Table 3-1a. ODF File Label Group Header Format (Cont'd)             
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|  19   |  I32   |   7  | File Creation Time (hhmmss)              |          
|  20   |  I32   |   8  | File Reference Date (YYYYMMDD)*          |          
|  21   |  I32   |   9  | File Reference Time (HHMMSS)*            |          
|==================================================================|          
                                                                              
              Table 3-2a. ODF Identifier Group Header Format                  
                                                                              
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  S32   |   1  | Primary Key = 107                        |          
|   2   |  I32   |   2  | Secondary Key = 0                        |          
|   3   |  I32   |   3  | Logical Record Length (in packets) = 1   |          
|   4   |  I32   |   4  | Group Start Packet Number (= 2)          |          
|   5   |  5*I32 |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
                                                                              
           Table 3-2b. ODF Identifier Group Data Format                       
                                                                              
|==========================================================================|  
| Item  | Pack   | Data |              Description                         |  
|Number | Format | Word |                                                  |  
|-------+--------+------+--------------------------------------------------|  
|  1- 8 |   8*I8 |  1-2 | "TIMETAG" - 8 ASCII "Characters"                 |  
|  9-16 |   8*I8 |  3-4 | "OBSRVBL" - 8 ASCII "Characters"                 |  
| 17-36 |  20*I8 |  5-9 | "FREQ, ANCILLIARY-DATA", - 20 ASCII "Characters" |  
|==========================================================================|  
                                                                              
                                                                              
* Currently the ODF timetags are referenced to EME50.  Hence, these two items 
are set to 19500101 (date) and 000000 (time) respectively.  Older files which 
have time reference dates equal to zero will be assumed to be EME50.          
                                                                              
                                                                              
_________________________________ end page 3-4 _______________________________
                                                                              
                                                                              
          Table 3-3a.  ODF Orbit Data Group Header Format                     
|=================================================================|           
| Item  | Pack  | Data |                Description               |           
|Number | Format| Word |                                          |           
|-------+---------+----+------------------------------------------|           
|   1   |   S32 |   1  | Primary Key = 109                        |           
|   2   |   I32 |   2  | Secondary Key = 0                        |           
|   3   |   I32 |   3  | Logical Record Length (in packets) = 1   |           
|   4   |   I32 |   4  | Group Start Packet Number (= 4)          |           
|  5-9  | 5*I32 |  5-9 | 0                                        |           
|=================================================================|           
                                                                              
_________________________________ end page 3-4 _______________________________
                                                                              
                                                                              
             Table 3-3b.  ODF Orbit Data Group Header Format                  
|============================================================================|
| Item | Pack |Data |Data |                Description                       |
|Number|Format|Word |Unit |                                                  |
|------+------+-----+-----+--------------------------------------------------|
|   1  |  I32 |  1  |sec  | Record Time Tag, integer part                    |
|   2  |  I10 |  2  |msec | Record Time Tag, fractional part                 |
|   3  |  I22 |     |nsec | [Primary] Receiving Station Downlink Delay       |
|   4  |  S32 |  3  |  *  | Observable, integer part                         |
|   5  |  S32 |  4  |  *  | Observable, fractional part (10^-9)              |
|   6  |  I3  |  5  |n/a  | Format ID = 2                                    |
|   7  |  I7  |     |n/a  | [Primary] Receiving Station ID Number            |
|   8  |  I7  |     |n/a  | Transmitting Station ID Number (0 if quasar VLBI,|
|      |      |     |     | 1-way {Doppler, phase, or range], or angles data)|
|  9   |  I2  |     |n/a  | Network ID of [Primary] Receiving Station        |
|      |      |     |     | 0 = DSN, Blovk V Exciter                         |
|      |      |     |     | 1 = Other                                        |
|      |      |     |     | 2 = OTS                                          |
|  10  |  I6  |     |n/a  | Data Type ID:                                    |
|      |      |     |     | 01=Narrowband spacecraft VLBI,Doppler mode;cycles|
|      |      |     |     | 02=Narrowband spacecraft VLBI,phase mode;cycles  |
|      |      |     |     | 03=Narrowband quasar VLBI,Doppler mode;cycles    |
|      |      |     |     | 04=Narrowband quasar VLBI, phase mode;cycles     |
|      |      |     |     | 05=Wideband spacecraft VLBI;nanoseconds          |
|      |      |     |     | 06=Wideband quasar VLBI;nanoseconds              |
|============================================================================|
                                                                              
* Units are spcified by item 10 (Data Type ID)                                
                                                                              
_________________________________ end page 3-5 _______________________________
                                                                              
                                                                              
         Table 3-3b.  ODF Orbit Data Group Data Format (Cont'd)               
                                                                              
|============================================================================|
| Item | Pack |Data |Data |                Description                       |
|Number|Format|Word |Unit |                                                  |
|------+------+-----+-----+--------------------------------------------------|
| 10   |      |     |     | 11=One-way Doppler;Hertz                         |
|Cont'd|      |     |     | 12=Two-way Doppler;Hertz                         |
|      |      |     |     | 13=Three-way Doppler;Hertz                       |
|      |      |     |     | 21=One-way Total-Count Phase;cycles              |
|      |      |     |     | 22=Two-way Total-Count Phase;cycles              |
|      |      |     |     | 23=Three-way Total-Count Phase;cycles            |
|      |      |     |     | 36=PRA Planetary Operational Discrete Spectrum   |
|      |      |     |     |    Range;range units                             |
|      |      |     |     | 37=SRA Planetary Operational Discrete Spectrum   |
|      |      |     |     |    Range;range units                             |
|      |      |     |     | 41=RE[GSTDN] range;nanoseconds                   |
|      |      |     |     | 51=Azimuth Angle;degrees                         |
|      |      |     |     | 52=Elevation Angle;degrees                       |
|      |      |     |     | 53=Hour Angle;degrees                            |
|      |      |     |     | 54=Declination Angle;degrees                     |
|      |      |     |     | 55=X Angle (where +X is East);degrees            |
|      |      |     |     | 56=Y Angle (where +X is East);degrees            |
|      |      |     |     | 57=X Angle (where +X is South);degrees           |
|      |      |     |     | 58=Y Angle (where +X is South);degrees           |
|  11  |  I2  |     | n/a | Downlink Band ID:                                |
|      |      |     |     |    0 = Not applicable if angle data,             |
|      |      |     |     |      = Ku-band otherwise                         |
|      |      |     |     |    1 = S-band                                    |
|      |      |     |     |    2 = X-band                                    |
|      |      |     |     |    3 = Ka-band                                   |
|  12  |  I2  |     | n/a | Uplink Band ID:                                  |
|      |      |     |     |    0 = Not applicable if angle data,             |
|      |      |     |     |      = Ku-band otherwise                         |
|      |      |     |     |    1 = S-band                                    |
|      |      |     |     |    2 = X-band                                    |
|      |      |     |     |    3 = Ka-band                                   |
|  13  |  I2  |     | n/a | Exciter Band ID:                                 |
|      |      |     |     |    0 = Not applicable if angle data,             |
|      |      |     |     |      = Ku-band otherwise                         |
|      |      |     |     |    1 = S-band                                    |
|      |      |     |     |    2 = X-band                                    |
|      |      |     |     |    3 = Ka-band                                   |
|  14  |  I1  |     |n/a  | Data Validity Indicator (0 = good, 1 = bad)      |
|============================================================================|
                                                                              
_________________________________ end page 3-6 _______________________________
                                                                              
         Table 3-3b.  ODF Orbit Data Group Data Format (Cont'd)               
                                                                              
|============================================================================|
| Item | Pack |Data |Data |                Description                       |
|Number|Format|Word |Unit |                                                  |
|------+------+-----+-----+--------------------------------------------------|
|  15  |  I7  | 6-7 |n/a  | 2nd Receiving Station ID Number if VLBI data;    |
|      |      |     |n/a  | Lowest (Last) Component if PRA/SRA range data;   |
|      |      |     |sec  | Integer Seconds of Observable if RE range data;  |
|      |      |     |n/a  | Channel Number if Doppler or phase data;         |
|      |      |     |n/a  | 0 otherwise                                      |
|  16  |  I10 |     |n/a  | Quasar ID if VLBI quasar data;                   |
|      |      |     |n/a  | Spacecraft ID otherwise                          |
|  17  |  I1  |     |n/a  | Modulus indicator if wideband VLBI data;         |
|      |      |     |n/a  | Receiver/Exciter independent flag if Doppler,    |
|      |      |     |     |   phase, or range data (0=no, 1=yes);            |
|      |      |     |n/a  | 0 otherwise                                      |
|  18  |  I22 |     |mHz  | Reference Frequency, H/P (0 if angles data)**    |
|  19  |  I24 |     |mHz  | Reference Frequency, L/P (0 if angles data)**    |
|  20  |  S20 |8-9  |n/a  | (Phase Calibration Flag minus 1) times 100,000   |
|      |      |     |     |  plus Channel ID Number times 10,000 if narrow-  |
|      |      |     |     |  band VLBI data;                                 |
|      |      |     |0.1ns| (Channel Sampling Flag minus 1) times 100,000    |
|      |      |     |     |  plus Mode ID Number times 10,000 plus Modulus   |
|      |      |     |     |  H/P if wideband VLBI data;                      |
|      |      |     |n/a  | 0 otherwise                                      |
|  21  |  I22 |     |nsec | (Modulus L/P)*10,000,000 if wideband VLBI data;  |
|      |      |     |0.1s | Compression Time if Doppler, phase, or narrowband|
|      |      |     |     |    VLBI data;                                    |
|      |      |     |sec  | Highest (First) Component times 100,000 plus     |
|      |      |     |     |  Downlink Ranging Transmitter Code In-Phase      |
|      |      |     |     |    Tome Offset from Sample Timetag if PRA/SRA    |
|      |      |     |     |    range data;                                   |
|      |      |     |n/a  | 0 otherwise                                      |
|  22  |  I22 |     |nsec | 2nd Receiving Station Downlink Delay,if VLBI data|
|      |      |     |nsec | Transmitting Station Uplink Delay if Doppler,    |
|      |      |     |     | phase, or range data;                            |
|      |      |     |n/a  | 0 otherwise                                      |
|============================================================================|
                                                                              
** Actually I46, but may be split as necessary for specific computers.        
                                                                              
_________________________________ end page 3-7 _______________________________
                                                                              
                                                                              
               Table 3-4a.  ODF Ramp Groups Header Format                     
                                                                              
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |   S32  |   1  | Primary Key = 2030                       |          
|   2   |   I32  |   2  | Secondary Key = Station ID Number        |          
|   3   |   I32  |   3  | Logical Record Length (in packets) = 1   |          
|   4   |   I32  |   4  | Group Start Packet Number                |          
|  5-9  |  5*I32 |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
                                                                              
                                                                              
               Table 3-4b.  ODF Ramp Groups Data Format                       
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  I32   |   1  | Ramp Start Time, integer part            |          
|   2   |  I32   |   2  | Ramp Start Time, fractional part (10^-9) |          
|   3   |  S32   |   3  | Ramp Rate, integer part(two's complement)|          
|   4   |  S32   |   4  | Ramp Rate, fractional part, (two's       |          
|       |        |      |    complement, 10^-9)                    |          
|   5   |  I22   |   5  | Ramp Start Frequency, integer GHz*       |          
|   6   |  I10   |      | Receiving/Transmitting Station ID Number |          
|   7   |  I32   |   6  | Ramp Start Frequency, integer part cont. |          
|       |        |      |    (modulo, 10^-9)                       |          
|   8   |  I32   |   7  | Ramp Start Frequency, fractional part    |          
|       |        |      |    (10^-9)                               |          
|   9   |  I32   |   8  | Ramp End Time, integer part              |          
|  10   |  I32   |   9  | Ramp End Time, fractional part (10^-9)   |          
|==================================================================|          
                                                                              
* If non-zero, ramp start frequency and ramp rate are at sky level            
                                                                              
_________________________________ end page 3-8 _______________________________
                                                                              
                                                                              
       Table 3-5a. ODF Clock Offsets Group Header Format                      
                                                                              
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  S32   |   1  | Primary Key = 2040                       |          
|   2   |  I32   |   2  | Secondary Key = 0                        |          
|   3   |  I32   |   3  | Logical Record Length (in packets) = 1   |          
|   4   |  I32   |   4  | Group Start Packet Number                |          
|  5-9  | 5*I32  |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
         Table 3-5b. ODF Clock Offsets Group Data Format                      
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  I32   |   1  | Start Time, integer part                 |          
|   2   |  I32   |   2  | Start Time, fractional part (10^-9)      |          
|   3   |  S32   |   3  | Clock Offset, integer part (two's        |          
|       |        |      |    complement)                           |          
|   4   |  S32   |   4  | Clock Offset, fractional part, (two's    |          
|       |        |      |    complement, 10^-9)                    |          
|   5   |  I32   |   5  | Primary Station ID Number                |          
|   6   |  I32   |   6  | Secondary Station ID Number              |          
|   7   |  I32   |   7  | 0 (spare)                                |          
|   8   |  I32   |   8  | 0 (reserved for End Time, integer part)  |          
|   9   |  I32   |   9  | 0 (reserved for End Time,fractional part)|          
|==================================================================|          
                                                                              
                                                                              
_________________________________ end page 3-9 _______________________________
                                                                              
                                                                              
       Table 3-6a. ODF Uplink Phase Group Header Format                       
                                                                              
|==================================================================|          
| Item  | Pack   | Data |                Description               |          
|Number | Format | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  S32   |   1  | Primary Key = 2050                       |          
|   2   |  I32   |   2  | Secondary Key = Station ID Number        |          
|   3   |  I32   |   3  | Logical Record Length (in packets) = 1   |          
|   4   |  I32   |   4  | Group Start Packet Number                |          
|  5-9  | 5*I32  |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
         Table 3-6b. ODF Uplink Phase Group Data Format                       
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  I32   |   1  | Start Time, integer part                 |          
|   2   |  I32   |   2  | Start Time, fractional part (10^-9)      |          
|   3   |  I32   |   3  | Uplink Phase, part 1*                    |          
|   4   |  I32   |   4  | Uplink Phase, part 2*                    |          
|   5   |  I32   |   5  | Station ID Number                        |          
|   6   |  I32   |   3  | Uplink Phase, part 3*                    |          
|   7   |  I32   |   4  | Uplink Phase, part 4*                    |          
|   8   |  I32   |   8  | 0 (reserved for End Time, integer part)  |          
|   9   |  I32   |   9  | 0 (reserved for End Time,fractional part)|          
|==================================================================|          
                                                                              
*  Uplink Phase (UP) is a quad precision (REAL*16) parameter that             
   is constructed as follows:                                                 
    UP = [(item 3) * 2**(40) + (item 4) * 2**(16) +                           
             (item 6) * 2**(-8) + (item 7) * 2**(-32)                         
                                                                              
                                                                              
_________________________________ end page 3-10 ______________________________
                                                                              
                                                                              
             Table 3-7a. ODF Data Summary Group Header Format                 
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  S32   |   1  | Primary Key = 105                        |          
|   2   |  I32   |   2  | Secondary Key = 0                        |          
|   3   |  I32   |   3  | Logical Record Length (in packets) = 1   |          
|   4   |  I32   |   4  | Group Start Packet Number                |          
|  5-9  | 5*I32  |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
                                                                              
             Table 3-7b. ODF Data Summary Group Data Format                   
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  I32   |   1  | First Sample Time, integer part          |          
|   2   |  I32   |   2  | First Sample Time, fractional part(10^-9)|          
|   3   |  I32   |   3  | Station ID Number                        |          
|   4   |  I32   |   4  | Doppler Channel Number () if VLBI, Range,|          
|       |        |      |   or Angles summary)                     |          
|   5   |  I32   |   5  | Band ID Number                           |          
|   6   |  I32   |   6  | Data Type ID Number                      |          
|   7   |  I32   |   7  | Number of Samples (in ODF)               |          
|   8   |  I32   |   8  | Last Sample Time, integer part           |          
|   9   |  I32   |   9  | Last Sample Time, fractional part (10^-9)|          
|==================================================================|          
                                                                              
                                                                              
_________________________________ end page 3-11 ______________________________
                                                                              
                                                                              
                                                                              
                   Table 3-8. ODF End-of-File Group Format                    
                                                                              
|==================================================================|          
| Item  | Length | Data |                Description               |          
|Number | (bits) | Word |                                          |          
|-------+--------+------+------------------------------------------|          
|   1   |  I32   |   1  | Primary Key = -1                         |          
|   2   |  I32   |   2  | Secondary Key = 0                        |          
|   3   |  I32   |   3  | Logical Record Length (in packets) = 0   |          
|   4   |  I32   |   4  | Group Start Packet Number                |          
|  5-9  | 5*I32  |  5-9 | 0                                        |          
|==================================================================|          
                                                                              
                                                                              
_________________________________ end page 3-12 ______________________________
                                                                              
                               Appendix A                                     
Doppler and Range Observables                                                 
                                                                              
Doppler and range observables, rather than the actual measurements made at the
Deep Space Stations, are provided in the ODF Orbit Data Group                 
(see Table 3b, items 3 and 4).                                                
                                                                              
The Doppler observable (in Hertz) is computed according to the following      
equation. The time tag is at the mid-point of the compression interval,       
ti to tj.                                                                     
                                                                              
Observable = B/|B|*[(Nj-Ni)/(tj-ti)-|Fb*K+B|]                                 
                                                                              
where:                                                                        
 B  = Bias frequency of measured Doppler                                      
 Ni  = Doppler count at time ti                                               
 Nj = Doppler count at time tj                                                
 ti  = start time of interval                                                 
 tj  = end time of interval                                                   
                                                                              
K = 1 for S-band receivers (Table 3b, Item 9)                                 
  = 11/3 for X-band receivers                                                 
  = 16/9 for Ku-band receivers                                                
  = 209/15 for Ka-band receivers                                              
                                                                              
Fb=X1/X2*(X3*Fr+X4)-Fsc+R3 for 1-way Doppler                                  
                                                                              
Fb=X1/X2*(X3*Fr+X4)-T1/T4*(T3*Ft+T4) for all other Doppler                    
                                                                              
 where:                                                                       
                                                                              
 Fr  = Receiver (VCO) frequency at time tr                                    
                                                                              
 FSC = Spacecraft (beacon) frequency                                          
                                                                              
 Ft = Transmitter frequency at time tr-RTLT                                   
                                                                              
 R3  = 0 for S-band receivers                                                 
     = 0 for X-band receivers                                                 
     = 0 for Ku-band receivers                                                
     = 0 for Ka-band receivers                                                
                                                                              
_________________________________ end page A-1 _______________________________
                                                                              
                                                                              
  T1 = 240 for S-band transmitters (Table 3b, Item 16)                        
     = 240 for X-band transmitters                                            
     = 142 for Ku-band transmitters                                           
     = 14 for Ka-band transmitters                                            
                                                                              
 T2 = 221 for S-band transmitters                                             
    = 749 for X-band transmitters                                             
    = 153 for Ku-band transmitters                                            
    = 15 for Ka-band transmitters                                             
                                                                              
 T3  = 96 for S-band transmitters                                             
     = 32 for X-band transmitters                                             
     = 1 for Ku-band transmitters                                             
     = 1 for Ka-band transmitters                                             
                                                                              
 T4  = 0 for S-band transmitters                                              
     = 6,500,000,000 for X-band transmitters                                  
     = 0 for Ku-band transmitters                                             
     = 0 for Ka-band transmitters                                             
                                                                              
X1 to X4 have the same values as T1 to T4 but are dependent                   
   on the exciter band (Table 3b, Item 15, 2nd subitem).                      
                                                                              
NOTE:                                                                         
                                                                              
When the reference frequency (Table 3b, items 15,20 and 21)                   
is provided at sky level, T3 and X3 are 1 for all bands,                      
and T4 and X4 are 0 for all bands.                                            
                                                                              
For range data, the observable is computed as follows:                        
                                                                              
 Observable = R - C + Z - S                                                   
                                                                              
where: R = range                                                              
 C = Station delay calibration                                                
 Z = Z correction                                                             
 S = Spacecraft delay                                                         
                                                                              
                                                                              
_________________________________ end page A-2 _______________________________
