The following power tests were conducted on GPS and GNSS antennas using an Agilent N6705 DC Power Analyzer. The following tests show short, 1-minute averages of measured power consumption. The power use of each antenna was tested at two separate... Read More

Permanent GNSS/GPS Station Planning: Technology, Equipment, Costs Permanent GNSS Stations for Geodetic Applications: Equipment, Sites, Costs -- S. Fisher This is intended as a primer for investigators wishing to implement permanent GNSS stations wit... Read More

Update: GPS/GNSS Interference From Iridium Data TransmissionsThe Iridium satellite communication system broadcasts in the 1610 to 1626.5 MHz band. UNAVCO Inc. uses iridium communication links to download GPS data from remote GPS stations. The L1 freq... Read More

The Iridium satellite communication system uses the 1616-1626.5 MHz band to uplink with orbiting communication satellites. UNAVCO Inc. uses iridium communication links to download GPS data from remote GPS stations located at high latitudes. The L1... Read More

Location: UNAVCO facility roof NE corner Author: Henry Berglund Contact: Berglund@unavco.org Introduction: Trimble currently offers two choke ring antenna designs for GNSS applications: The Trimble GNSS Choke Ring Antenna has a traditional Dorne... Read More

GNSS Antenna Phase Center Stablity Test - TPSPG_A1+GP Background Topcon TPSPG_A1+GP Campaign Height Measurement Bias Problems were reported by Bob King, Adrian Borsa and other investigators regarding height estimate biases introduced when using... Read More

This article presents a comparison of measured signal to noise ratio (SNR) values observed from several  GNSS antenna types. The results presented below were collected using a monument located on the UNAVCO Facility Roof in Boulder, CO. Each... Read More

Introduction to GNSS Antenna Set-up Methods for Campaigns When collecting geodetic data, the GPS antenna is set up over the particular point of interest. For high accuracy crustal applications, the actual survey mark is precisely defined, typically... Read More

How to use declination to align the GNSS antenna to true north For consistency both within and between campaign GPS surveys, GPS antennas are generally aligned to true north (antenna elements may be asymmetrical). Most antennas have markings... Read More

Title: Testing the Susceptibility of GNSS Receivers to Radio Frequency Interference Authors: Henry Berglund, Frederick Blume, Warren Gallaher Date: 2015 Summary:  To better characterize GNSS receiver susceptibility to more general RF... Read More