The potential of using the Global Positioning System (GPS) for geophysical and geodetic measurements has been demonstrated in a number of recent studies showing baseline accuracies of 0.1- 0.01 ppm. The success of GPS has led to a growing number of tectonic studies around the globe and has created an ever- increasing demand for more receivers to supplement and replace the now discontinued TI4100 receiver. This has prompted the development of a number of new, more portable, lower cost, and perhaps more accurate GPS receivers. The PIs will systematically test new GPS receiver and antenna designs to determine how various instruments can be combined in one campaign without losing the high accuracy previously obtained with single receiver data. The multipath characteristics of the new antennae will be compared.
