NavCom StarUtil Rev.E - Manual (Page 44)

STARUTIL User Guide Rev. E
successful completion or proximity failure, this request will return the reported
QuickStart mode to ‘Idle’.
c. A QuickStart ‘reset’ request has been requested. This causes a restart of the entire
RTG navigation mode with no a-priori position information i.e. full pull-in duration.
2. Initiated: This mode is reported after a QuickStart initiation request has been received but
before the QuickStart operation has actually started. The QuickStart operation will not begin
until RTG navigation commences. This requires at least five satellites each with full dual
frequency tracking and at least 10 seconds of code-carrier smoothing. If, for example, a
QuickStart initiation request is given shortly after power-on, it may be a few minutes before
these conditions are met. During this period, the reported QuickStart mode would be
‘Initiated’.
3. In Progress: This mode is reported after a QuickStart has actually commenced up until the
time that either the operation completes or fails or until an ‘Idle’ or ‘Reset’ request are
received.
4. Completed: This mode is reported when a QuickStart operation has completed successfully.
It takes 50 seconds from the time the QuickStart first begins (In Progress reported) until
successful completion is reported.
5. Failed Proximity Limit: While a QuickStart operation is in progress, a check is performed at
each 1Hz navigation epoch, which compares the 3D radial distance between the RTG code
solution and the ‘known’ position input with the QuickStart initiation request. If this
distance exceeds 25 meters on the first QuickStart epoch, or 15 meters on any of the
subsequent epochs in the 50 second period, the QuickStart is terminated, RTG navigation is
reset (full pull-in required), and the QuickStart mode is reported as ‘Failed Proximity Limit’.
The RTG code solution is the weighted least squares navigation solution performed with
smoothed code (could be single or dual frequency depending on prefilter status) and RTG
clock and orbit corrections. It is independent from the full RTG solution, which uses the
phase biases, estimated by the RTG extended Kalman filter. It is the latter, which is initialized
by a QuickStart operation.
‡
For example, vehicular installations can be initialized using the last position from when it was
parked and powered down.
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