AIDJEX Bulletin #40 - Polar Science Center - University of Washington

function of time, control of the receiver search frequency, and the ability
to break off from a satellite after the end of the critical interval.
From a total of 81 passes per day, generally 30-50 were chosen to be
tracked. Only 50%-70% of the passes selected were actually tracked, due to
shortcomings in the control of the receivers. The principal difficulty was
interference of unwanted signals while trying to position the receiver
frequency at the frequency of the desired satellite. However, early breaking
from passes probably increased the number of fixes over what would have been
expected from conventional automatic acquisition receivers. Proper implementation
of the concept should result in nearly 100% success in tracking the
desired passes and would increase the quantity and quality of data collected
in high latitudes, especially during clustering of satellite passes.
The average number of fixes from successfully tracked passes was 30 per
day (Fig. 5). For each pair of stations, we typically acquired 20 translocation
fixes per day.
c
Q,
Fig. 5. Typical distribution of
fixes per day from a receiver
for the full year of the main
experiment. The histogram 0
includes effects of system
down-time, imperfect
>
receiver control, and vari- 0
ations in clustering of
satellite passes.
3
0
W
& 20
5 IO
a
LL
'0 10 20 30 40 50 60 70
GOOD FIXES PER DAY
90