Does Differential GPS (DGPS) techiques similar with Real Time Kinematic (RTK) surveying technique?

Answer 1

DGPS and RTK are very different techniques!!

Both techniques use a two receivers each. The base receiver is set up over a known position. The roving receiver (presumably you). Data is collected at this base station and is either sent to the rover via some form of telecom link (real-time) or stored to be processed later (post-processed). This is where the similarities end.

DGPS uses only GPS pseudoranges to compute its position. There are going to be errors in this computation due to atmospheric effects (e.g. ionosphere, troposphere, etc). By having the base station over a known position, these errors in the pseudoranges can be estimated. If the roving receiver (you) is "close" to the base station, its assumed that the pseudorange errors are similar. So the roving receiver applies those pseudorange errors to its pseudoranges and [presumably] gives a more accurate position. Accuracy for this technique is on the order of sub-meter. This can be done in either real-time or post-processed. This technique is available to many recreational-use handheld devices and is generally inexpensive.

RTK (real-time kinematic) uses not only pseudoranges for computing position, but also carrier phase and doppler measurements. The base station will collect these data and transmit them to the roving receiver. RTK systems are part of a "survey-grade" line of products of GPS receivers. Without going into the gory detail, survey-grade receivers don't compute position per se. Rather they compute the baseline (dx, dy, dz) between the base and rover. Because the base is over a known coordinate and because the baseline can be computed to millimeter accuracy, the position of the rover can be deduced to millimeter accuracy. This accuracy comes at great expense though. RTK systems usually are on the order of tens of thousands of dollars.

Though the term RTK implies real-time, post-processed kinematic techniques were around long before RTK.

Answer 2

They are similar exept it is possible to get dgps without a radio connection between the reference gps receiver and the mobile unit. The differential corrections can be applied after the fact of measurement by keeping a time log. The corrections, while significant, change very slowly.

Answer 3

Real Time Kinematics

Answer 4

Chris Parker and Mike Williams asked the same question. You should see the answers side by side.

Answer 5

Sorry, not sure about this