User`s guide

Appendix
Motorola GPS Products - M12+ User's Guide Revision 6.X 09FEB05
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SPS
Standard Positioning Service, uses the C/A code to provide a minimum level of dynamic
or static positioning capability. The accuracy of this service is set at a level consistent
with national security. See Selective Availability.
Squaring-Type Channel
A GPS receiver that multiplies the received signal by itself to obtain a second harmonic of
the carrier that does not contain the code modulation. Used in codeless receiver designs
to obtain dual frequency measurements.
Static Positioning
Positioning applications in which the positions of static or near-static points are
determined.
SV
Satellite vehicle or space vehicle.
Switching Channel
A receiver channel that is sequenced through a number of satellite signals (each from a
specific satellite and at a specific frequency) at a rate which is slower than, and
asynchronous with, the message data rate.
TDOP
Time Dilution of Precision. See Dilution of Precision.
Time to First Fix (TTFF)
Average time (usually expressed in seconds) required for a given GPS receiver to
develop a position fix after power is applied. For Motorola receivers, first fix is defined as
a 2D fix for positioning receivers and a3D fix for timing receivers. See Cold Start, Hot
Start, and Warm Start.
TOW
Time of week, in seconds from midnight Saturday UTC.
T-RAIM
Time Receiver Autonomous Integrity Monitoring. This is an algorithm that continuously
monitors the integrity of the time solution by using redundant satellite measurements.
This algorithm is only available on the M12+ timing receiver. See the T-RAIM Setup and
Status Message (@@Hn) in Chapter 5.
Translocation
A version of relative positioning that makes use of a known position, such as an NGS
survey mark, to aid in accurately positioning a desired point. The position of the mark,
determined using GPS, is compared with the accepted value. The three-dimensional
differences are then used in the calculations for the second point.