AshtechInstant-RTKª: A Revolutionary Solution for Surveying Professionals

Real-time Kinematic (RTK) GPS positioning is extensively used in precision positioning and surveying applications. RTK involves carrier phase ambiguity resolution, which is qualified based on three main characteristics; namely, accuracy, reliability and time to fix. The state-of- the-art AshtechInstant-RTK a technology serves all these requirements. The integer ambiguities are initialized instantly allowing for immediate centimeter-accuracy positioning for high-speed productivity. Instant-RTK with ambiguities fixed within five seconds at 99.9% reliability is achievable with PDOP less than five, six or more satellites tracked on both L1 and L2 frequencies, baseline length less than seven kilometers and at locations with no severe multipath sources nearby. This paper presents test results demonstrating the performance of the Ashtech Instant-RTK technology as featured in the Z-Xtremea GPS receiver under different operating conditions and over various baseline lengths. Static and kinematic positioning accuracy of 0.005m+1ppm horizontal and 0.010+1ppm vertical, and 0.010+1ppm horizontal and 0.020+2ppm vertical (standard error), respectively, is demonstrated.