PHOTOGRAMMETRIC APPLICATIONS OF SERCEL GPS TR5S-B 
RECEIVER AT INSTITUT GEOGRAPHIQUE NATIONAL - FRANCE 
R. BROSSIER, C. MILLION and A. REYNES 
Institut Géographique National 
2, avenue Pasteur 
94160 ST MANDE 
FRANCE 
Commission I, Working group I/3 
Abstract 
IGN-F has realized in 1986 and 1987 two test campaigns with a 
GPS TR5S-B receiver built by SERCEL company. Theaim of these 
operations was the evaluation of the contribution of this mate- 
rial, not only for navigation but mainly for photogrammetric 
purposes. 
A first aspect of the paper concerns a description of the on- 
board system. Then results are presented when using two levels 
Of accuracy for GPS data and testing differential measurements 
with a fixed receiver. Aerial triangulation computations take 
into account GPS data and several hypothesis are considered, 
concerning use of control groundpoints. 
it is shown that it is possible, to eliminate all control ground 
points for medium scales surveys, except one point at the cen- 
ter of the block for tving up.to, the geodetic network. 
A last aspect concerns use of GPS data for aerial survey itself, 
even when NAVSTAR constellation configuration is degraded, and 
for automatic drawing up of flight indexes. 
I) Introduction 
The Global Positioning System NAVSTAR has been already presen- 
ted in many other papers, concerning its civil applications in 
geodesy and for maritime, terrestrial and aerial navigation. 
But exploration of its abilities for photogrammetry has only 
begun recently. 
In 1986 IGN has realized its first flights tests with SERCEL 
company. A preliminary step consisted of verifying the recep- 
tion quality of GPS signals on an airplane and evaluating re- 
liability of GPS position determination relative to photogram- 
metric calculation. These trials were done, at great scale, 
with a low speed Aerocommander aircraft. Another operation at 
medium scale has been conducted in 1987 with a fast Mystere 20 
aircraft, for a more complete investigation of photogrammetric 
applications of GPS. 
This paper presents the both flight tests and results after 
photogrammetric computation.