[time-nuts] Important parameters for a GPS/GNSS antenna

[Tom Van Baak]

> A tri-band antenna design is... uh.. difficult.
> At the moment I am just playing with some software. Yes, I might
> end up with something that resembles an antenna design. But with my level of
> knowledge getting a good single band antenna would be already quite
> some feat. Designing a multi-band antenna is way out of my league.
> 
> Attila Kinali

Hi Attila,

One other consideration is that for high-end positioning and timing use, an accurate characterization of a given antenna is more important than trying to achieve a "perfect" antenna. When you post-process raw GPS data you get to include antenna phase center / gain / az/el corrections for free. This means the goal is not so much a perfect antenna design, but an antenna whose imperfections are well-known.

Here are a dozen random GPS antenna calibration links to keep you busy for today:

National Geodetic Survey Absolute Antenna Calibrations
http://www.gps.gov/cgsic/meetings/2010/bilich.pdf

Leica GNSS Reference Antennas - White Paper
http://www.leica-geosystems.com/downloads123/zz/nrs/general/white-tech-paper/Leica_Reference_Antennas_Whitepaper_TPA_en.pdf

A Novel GPS Survey Antenna
http://www.meridware.com.tw/Documents/Papers/gps600antenna.pdf

Tests of phase center variations of various GPS antennas, and some results
ftp://geodesy.noaa.gov/pub/abilich/oldPC/Documents/antcal/calibPapers/Schmitz2002.pdf

GPS ANTENNA CALIBRATION AT THE NATIONAL GEODETIC SURVEY
https://www.fig.net/pub/fig2008/ppt/ts05g/ts05g_02_weston_mader_ppt_2857.pdf

A New Approach for Field Calibration of Absolute Antenna Phase Center Variations
http://www.geopp.com/pdf/ion96.pdf

ANTENNA PHASE CENTER VARIATIONS CORRECTIONS IN PROCESSING
OF GPS OBSERVATIONS WITH USE OF COMMERCIAL SOFTWARE
http://www.uwm.edu.pl/wnt/technicalsc/tech_13/B12.PDF

Phase center variations problem in GPS/GLONASS observations processing
http://leidykla.vgtu.lt/conferences/ENVIRO_2014/Articles/5/202_Dawidowicz.pdf

Calibration of antenna-radome and monument-multipath effect of
GEONET—Part 1: Measurement of phase characteristics
http://svr4.terrapub.co.jp/journals/EPS/pdf/2001/5301/53010013.pdf

Absolute phase center corrections of satellite and receiver antennas
http://www.dgfi.tum.de/media/jahresbericht/publications/4558dbb6f6f8bb2e16d03b85bde76e2c.pdf

Phase Center Calibration and Multipath Test Results of a Digital Beam-Steered Antenna Array 
http://navsys.com/Papers/0309002.pdf

/tvb