(5) Accuracy of stop-and-go baseline measurements will usually well exceed 1 part in 5,000;
therefore, third-order classification for horizontal control can be effectively, efficiently, and accurately
established using this technique. For many projects, this order of horizontal accuracy will be more than
adequate; however, field procedures should be designed to provide adequate redundancy for open-ended
or spur points. Good satellite geometry and minimum multipath are also essential in performing
acceptable stop-and-go surveys.
c. Kinematic Surveying. Kinematic surveying using differential carrier phase tracking is similar to
stop-and-go kinematic and static differential carrier phase GPS surveying because it also requires two
receivers recording observations simultaneously. Kinematic surveying is often referred to as dynamic
surveying. As in stop-and-go surveying, the reference receiver remains fixed on a known control point
while the roving receiver collects data on a constantly moving platform (such as a vehicle, a vessel, an
aircraft, or a backpack). Unlike stop-and-go surveying, kinematic surveying techniques do not require
the rover receiver to remain motionless over the unknown point. The observation data are later
postprocessed with a computer and the relative vector or coordinate differences to the roving receiver
are calculated.
(1) A kinematic survey requires two L1 receivers. One receiver is set over a known point
(reference station) and the other is used as a rover (moved from point to point or along a path). Before
the rover receiver can move, a period of static initialization or antenna swap must be performed. This
period of static initialization is dependent on the number of satellites visible. Once this is done, the
rover receiver can move from point to point as long as satellite lock is maintained on at least four
common satellites (common with the known reference station). If loss of lock occurs, a new period of
static initialization must take place. It is important to follow manufacturers' specifications when
performing a kinematic survey.
(2) Kinematic data-processing techniques are similar to those used in static surveying. When
processing kinematic GPS data, the user must ensure that satellite lock is maintained on four or more
satellites and that cycle slips are adequately resolved within the data recorded.
(3) Differential (carrier phase) kinematic survey errors are correlated between observations
received at the reference and rover receivers, as in differential static surveys. Experimental test results
indicate kinematic surveys can produce results in centimeters. Test results from an experimental full-
kinematic GPS-S conducted by Topographic Engineer Center (TEC) personnel at White Sands Missile
Range, New Mexico, verified (under ideal test conditions) that kinematic GPS surveying could achieve
centimeter-level accuracy over distances up to 30 kilometers.
d. Pseudokinematic Surveying. Pseudokinematic GPS surveying is similar to stop-and-go
surveying except that loss of lock is tolerated when the receiver is transported between occupation sites
(the roving receiver can be turned off during
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