Novatel 15a Car Satellite TV System User Manual


 
82 EuroPak-15a Receiver User Manual Rev 5
Chapter 6 Data Logs
6.3.5 RANGE Satellite Range Information
RANGE contains the channel measurements for the currently tracked satellites. When using this log, please
keep in mind the constraints noted along with the description.
It is important to ensure that the receiver clock model is valid. This can be monitored by the bits in the Receiver
Status field of the log header. Large jumps in pseudorange as well as accumulated Doppler range (ADR) will
occur as the clock is being adjusted. If the ADR measurement is being used in precise phase processing, it is
important not to use the ADR if the parity known flag in the ch-tr-status field is not set as there may exist a half
(1/2) cycle ambiguity on the measurement. The tracking error estimate of the pseudorange and carrier phase
(ADR) is the thermal noise of the receiver tracking loops only. It does not account for possible multipath errors
or atmospheric delays.
If a PRN is being tracked on more than one signal (GPS L1, GPS L5, Galileo L1 or Galileo E5a) multiple
entries with the same PRN will appear in the range logs. As shown in Table 40 on Page 84, these entries can be
differentiated by bits 21-22 of the ch-tr-status field, which denote whether the observation is for GPS L1, GPS
L5, Galileo L1 or Galileo E5a. This is to aid in parsing data.
Log Type: Synch Message ID: 43
Field
Field
Name
Description Format
Binary
Bytes
Binary
Offset
1 header
This field contains the message header, in ASCII or Binary format. See
Section 4.3 on Page 35.
H 0
2 # obs Number of data sets to follow. Long 4 H
3 PRN Satellite PRN number of range measurement. UShort 2 H+4
4 Reserved UShort 2 H+6
5 psr Pseudorange measurement (m). Double 8 H+8
6 psr std Pseudorange measurement standard deviation (m). Float 4 H+16
7 adr Carrier phase, in cycles (accumulated Doppler range). Double 8 H+20
8 adr std Estimated carrier phase standard deviation (cycles). Float 4 H+28
9 dopp Instantaneous carrier Doppler frequency (Hz). Float 4 H+32
10
C/N
0
Carrier to noise density ratio
C/N
0
= 10[log
10
(S/N
0
)] (dB-Hz)
Float 4 H+36
11 locktime
Number of seconds of continuous tracking (no cycle
slipping).
Float 4 H+40
12
ch-tr-
status
Tracking status. See Table 40 on Page 84. ULong 4 H+44
13... Next data set, offset = H + 4 + (# previous obs x 44)
variable 32-bit CRC (ASCII and Binary only) Hex 4
H+4+
(#obs x
44)