POSITION PRECISION ANALYSIS OF THE DUAL FREQUENCY LOW COST GPS MODULE MEASUREMENT WITH STATIC DIFFERENTIAL METHOD IN VARIOUS BASELINE LENGTH VARIATIONS

GPS is a positioning technology using satellites that can be used globally. However, GPS receiver devices are classified as an expensive technology so costs become a problem. Low cost dual frequency GPS module are recently developed as an alternative in positioning system, with a lower price and has the ability to capture dual frequency GPS signals. This study is intended to research about the positioning precision of low cost dual frequency GPS module measurement and compare its ability to geodetic GPS dual frequency receiver for static differential positioning method in various baseline length variations. The variations in the length of the baseline are 0.1, 2, 10, 20, 30, 40, and 50 km. There are two stages of measurement, the first measurement using geodetic GPS receiver and second use low cost GPS module with both interval are 15 seconds and 15 elevation mask angel. Then the results are compare with geodetic GPS result as a reference. Based on the results of measurement and comparison of data, the range of the horizontal precision values of the geodetic GPS receiver is 3-9 mm, while the GPS module ranges from 3-29 mm. For vertical precision geodetic GPS receiver is better than low cost GPS module with cm level. But in some baseline length low cost GPS module precision is superior.