Abstract: A surveyor range pole, for example, equipped with a GPS receiver and antenna mounted at the top end, a battery mounted at the bottom end to better balance the pole, a tilt sensor and a direction sensor. The tilt sensor and direction sensor provide information about the vector that lies between the top and the bottom points of the range pole. The GPS receiver computes the position of the top end of the range pole from GPS satellite signals received by the GPS at the top end, and then computes the position of the bottom end of the range pole with the vector information. A variable length, telescoping range pole includes a linear transducer for automatically measuring the overall length of the range pole and contributing that length information to the vector calculation.

Abstract: Apparatus for measuring surveying parameters, such as distances and angular displacements between survey stations, with improved accuracy. The invention combines a differential satellite positioning system (SATPS), available with positioning systems such as GPS and GLONASS, with electromagnetic measurements of distances and optically encoded angles by a conventional electro-optical survey instrument to provide survey measurements that can be accurate to within a few millimeters in favorable situations. The differential satellite positioning system relies upon carrier phase measurements, after removal of certain phase integer ambiguities associated with carrier phase SATPS signals. The SATPS may be retrofitted within the housing of the conventional electro-optical instrument.