Implementing a professional quality DGPS receiver requires a code + carrier GPS receiver. The carrier phase is used to smooth the code phase, thereby reducing the noise on the code measurement and improving the resulting position accuracy. In addition to good quality GPS receiver, the antenna needs to have good phase center stability and multipath characteristics. With a good combination it is possible to get submeter accuracy using the commercially available DGPS corrections, such as radio beacon systems.

Good combinations for DGPS are:

• CSI Wireless SX-2 and CDA-RTK antenna
• Javad JNS100 and MarAnt L1
• Ashtech DG-14 and Marine IV antenna
• Novatel OEMV product family and 700 antenna

Dual frequency GPS receivers are used for geodetic applications, RTK measurements and applications that need centimeter accuracy. The second frequency is used to compute the ionosphere making the solution very accurate (geodesy) or accurate+possible (RTK).

Good combinations for geodesy and RTK are:

• Novatel OEMV product family
• Javad GD and GGD product family