Which system is generally more accurate, GPS or DGPS?

Which system is generally more accurate, GPS or DGPS?

• A. GPS
• B. DGPS
• C. Both are equally accurate
• D. Neither is reliable

Answer: (B)

The correct answer is that DGPS (Differential Global Positioning System) is generally more accurate than standard GPS (Global Positioning System). The key difference lies in how the two systems correct for inaccuracies. GPS on its own can achieve an accuracy of about 10 to 15 meters under typical conditions. This level of accuracy can be affected by various factors including atmospheric conditions, satellite geometry, and obstructions such as buildings or trees. DGPS, however, enhances GPS accuracy by using a network of fixed, ground-based reference stations that know their precise location. These reference stations continuously monitor the signals from GPS satellites and calculate the difference between their known fixed position and the position indicated by GPS signals. This calculated error is then broadcast to nearby GPS receivers, allowing them to correct their own calculations and improve their accuracy to within about 1 to 3 meters. The benefit of DGPS is particularly significant in applications requiring high precision, such as marine navigation, aviation, and surveying. Therefore, DGPS can provide a more reliable and accurate positioning solution compared to standard GPS alone.

The correct answer is that DGPS (Differential Global Positioning System) is generally more accurate than standard GPS (Global Positioning System). The key difference lies in how the two systems correct for inaccuracies.

GPS on its own can achieve an accuracy of about 10 to 15 meters under typical conditions. This level of accuracy can be affected by various factors including atmospheric conditions, satellite geometry, and obstructions such as buildings or trees.

DGPS, however, enhances GPS accuracy by using a network of fixed, ground-based reference stations that know their precise location. These reference stations continuously monitor the signals from GPS satellites and calculate the difference between their known fixed position and the position indicated by GPS signals. This calculated error is then broadcast to nearby GPS receivers, allowing them to correct their own calculations and improve their accuracy to within about 1 to 3 meters.

The benefit of DGPS is particularly significant in applications requiring high precision, such as marine navigation, aviation, and surveying. Therefore, DGPS can provide a more reliable and accurate positioning solution compared to standard GPS alone.