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[TCA] The TCA device is unable to use the found satellites

  [KB25362] Show Article Properties


Summary:
This article describes the issue of the TCA device being unable to use the found satellites.
Symptoms:
The TCA device is unable to acquire and use satellites as a valid reference. A Satellite can be found, but not usable, if the SNR (signal-to-noise) or Signal Status value is less than 4 AMU.
TCA8K> show gps
Receiver Description: GPS
Receiver Status: No Usable Satellites
Antenna Voltage: 5v
Cable Delay Compensation: 0 ns
Antenna Status: GOOD
Position: 0 0'0.0000'' S; 0 0'0.0000'' W;
Altitude: 0.00 m
Satellite num: 2
Sat Number Signal Status
23 3.600000AMU Acquired
16 2.800000AMU Acquiring
TCA8K>
Cause:
For a satellite to be usable, the SNR needs to be greater than 4.00 AMU. If the antenna and line of sight is good, the TCA device should be able to acquire a minimum of 6 satellites. In the following output, the TCA device has found 11 satellites; but only 9 are useable:
TCA8K> show gps
Receiver Description: GPS
Receiver Status: Good
Antenna Voltage: 3.3v
Cable Delay Compensation: 0 ns
Antenna Status: GOOD
Position: 42 34'25.7593'' N; 71 24'42.0007'' W;
Altitude: 69.93 m
Satellite num: 11

Sat Number Signal Status
16 6.800000AMU Acquired
29 8.400000AMU Acquired
31 9.400000AMU Acquired
32 13.200001AMU Acquired
14 10.600000AMU Acquired
23 6.800000AMU Acquired
30 10.600000AMU Acquired
20 8.400000AMU Acquired
25 6.800000AMU Acquired
6 1.600000AMU Acquiring
26 3.600000AMU Acquired

TCA8K>
Solution:
Check the antenna type or line of sight for possible issues.
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