TriPoint VertexRSI 7200, Руководство по эксплуатации и обслуживанию

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2.10 T r ack i ng Fun c t i ons
The 7 2 0 0 A C U a ll o w s a user to conf i gure up to 5 0 targets for estab li shment of
target-spec i f i c data bases (refer to paragraph 5.8.2.6). The fo ll o w i ng track i ng modes
are ava il ab l e:
Mov e to l oo k a ng l e s (refer to paragraph 2.9.1)
Mov e to l ong i tud e (refer to paragraph 2.9.2)
I nt e l s a t 11- e l e m e nt
O r b i t P r e d i c t i on T r ack i ng ( O P T )
St a r t r ack i ng (refer to paragraph 2.9.4)
2.10.1 I nt e l s a t 11- e l e m e nt T r ack
In th i s mode, the antenna i s moved accord i ng to po i nt i ng data generated us i ng the
Inte l sat E l even Parameter Mode l . The A C U accepts e l ement sets as d i str i buted by
Inte l sat, as w e ll as l oca l s i te data, and ca l cu l ates the correspond i ng pred i cted A Z and
EL pos i t i ons a l ong the ephemer i s. The antenna i s then moved to the pred i cted
pos i t i ons w i th suff i c i ent frequency to ma i nta i n po i nt i ng w i th i n a user-se l ectab l e
deadband around the theoret i ca l va l ues. A ga i n, the data for a g i ven target i s
ma i nta i ned i n a ded i cated data base for that target and i s cont i nua ll y updated to
prov i de appropr i ate pos i t i on i ng anyt i me the target i s accessed (w i th i n t i me of va li d i ty
constra i nts).
2.10.2 O r b i t P r e d i c t i on T r ack i ng
The OPT system prov i des except i ona l short-term and l ong-term po i nt i ng capab ili t i es
by comb i n i ng orb i ta l mechan i cs w i th modern mode li ng and error ana l ys i s techn i ques.
Orb i ta l mechan i cs are used to prov i de a mode l of the sate lli te’s and earth’s surface
mot i on. The mode li ng and error ana l ys i s takes po i nt i ng data co ll ected i n St e pt r ack
operat i ons and f i nds the sate lli te orb i ta l parameters and systemat i c errors caused by
the mechan i ca l structure w h i ch prov i de the best l east squares so l ut i on. The orb i ta l
parameters and systemat i c errors are then fed back through the orb i ta l mechan i cs
mode l s to determ i ne antenna l ook ang l es at any future po i nt i n t i me. The mode l s
accurate l y match the " rea l w or l d " and prov i de exce ll ent rea l w or l d resu l ts. (Refer to
paragraph 3.1).