UNAVCO Logo
 
 
Projects Help with Projects Project Support & Services Polar Services What's New Remote Station Technology Polar Geodetic Data GPS Support LiDAR Support GPS Base Stations External Polar-Related Links

Palmer Station GPS Survey System - Base Station


Base Station PAL2

A geodetic quality GPS base station is located in the IMS (TerraLab) facility at Palmer Station. The system consists of a Trimble NetR8 GPS receiver attached via an antenna splitter to an Ashtech Choke Ring antenna, which is located on geodetic monument PALM. Two other GPS base stations at Palmer, both operated by UNAVCO, are also connected to the same GPS antenna: IGS base station PALM (Ashtech receiver) and its backup PALV (Javad receiver).

A Pacific Crest RFM96W radio transmitter is connected to receiver PAL2, and broadcasts real-time kinematic (RTK) corrections to allow local real-time surveys and stakeouts up to 5 km from Palmer Station. The base can also be used for post-processed surveys up to a 100 km radius. A shared computer is available for data downloading and processing. The system is considered to be a permanent base station, and is not intended to be moved or disconnected.

Coordinates

Base Station PAL2 Coordinates. Coordinates are 0.0794m below bottom of antenna mount; antenna is Ashtech Choke Ring with Radome (ASH700936D_M SCIS).

Coordinate Value Ref. Frame
Latitude 64° 46' 30.32726" S WGS-84
Longitude 64° 03' 04.04752" W WGS-84
Height Above Ellipsoid (HAE) 30.942m WGS-84
Elevation Above MSL 15.222m EGM96.
Note: Value for Elevation above MSL corrected May 2013. Previously listed 15.720m

See the on-line NGS calculator for reference frame transformations.

Data Download

Users at Palmer Station can download base station data from Trimble NetR8 web interface:

This will bring up the receiver's web interface. The receiver is programmed to allow anonymous access for data download, however if prompted, the username and password are:

Username: pal2
Password: gps

The web interface also allows you to see how many satellites the receiver is tracking, what data files are being logged, and other configuration information. However, you can only download data using this user account and cannot change any of these parameters. Configuration changes are done remotely by UNAVCO using a separate account; contact UNAVCO for any changes or requests.

To download data, next click on the Data Logging tab, then Data Files. Click on the Internal directory then navigate to the directory where the desired files are stored. When you locate the file(s) you want, click on the filename to download. Note that you cannot download any files that are currently being written to. The NetR8 is configured to log files in the following locations:

24-hour 15-second datafiles
/Internal/YYYYMM/24hr15sc/PAL2YYYYMMDD0000A.T01

60-minute 2-Hz datafiles
/Internal/YYYYMM/DD/1hr2hz/PAL2YYYYMMDDHH00B.T01

60-minute 10-Hz datafiles
/Internal/YYYYMM/DD/1hr10hz/PAL2YYYYMMDDHH00C.T01

Each of these file types is allocated a certain portion of the NetR8 memory. When this section of memory is full, the oldest files are deleted. The NetR8 stores approximately 800 days of 15-second data, 40 days of 2Hz data, and 8 days of 10Hz data.

The 15-second data are also available from the UNAVCO data archive (site PAL2). Each summer season, from late October through mid February, high-rate data files are downloaded and archived by UNAVCO. However in general the higher sample rate data are recorded on the receiver only and are not archived. Due to the limited storage space for high-rate data on the receiver, any group requiring high-rate GPS data from this station should make a formal request as soon as possible by emailing archive-gpsunavco.org.

 

Last modified: 2019-12-24  02:12:46  America/Denver