Figure 7 shows the experimental configuration of
RTK-GPS positioning. First the authors tried
positioning at a fixed point on land in Tokyo University
of Mercantile Marine. The GPS antenna is about 20 m
high above the mean sea level on the roof of a 5-storied
building. Simultaneous positioning was tried with
three 4000SSi’s and a single GPS antenna, using CMR
data transmission from Nerima GPS-based CS (base
line length: 17 km).