Aut O S Y Nchron Ization Mode; Pul Se Synch Roniza Tion Mo De; Pul Se Sp Ecificat Ion - Aeroflex 3900 Series Option Manual

A u t o S yn c h r o n i z at io n M o d e
The dow nlink sig nal f rom t he B ase S tat ion un der test is fe d to the RF input of the Test Set . The
SY NC bur sts f rom this sig nal a re u se d to estab lish t he cur rent posit ion in th e dow nlink fra me
stru cture . The si gnal g enera ted b y the Test Set is a utomat ically t imed t o pr ovide co rre ct
synchron ization wi th t he ba se stat ion.
W h e n A u t o m a t i c i s se l e c t e d on t h e B a s e S t a t i o n I de n t i t y P a r a m e t e r s ar e a o f t h e
Syste m ID and Sync C onfig urat ion T
a u t o m a t i ca l l y u s e s t h e M C C - M N C - B C C v a l u e s c ap t u r e d i n t h e s y n c b u r s t f o r s c r am b l i n g .
The Aut o Syn c Pat h Off set p aramet er co ntr ols th e time off s et be twe en t he dow nlin k fr ame str uctur e
and t he T1 U plink S ignal from t he Test Set wit hin th e rang e -999 9.99 symbol s to +99 99.99 symbol s.
Posit ive valu es advance the timing o f th e Test Set signa l, causi ng the signal to be gener ated ear lier;
negat ive valu es dela y the timing of the Test Set signal rela tive t o t he base stat ion do wnli nk fr ame
stru cture .
Pu ls e S yn ch r o n i z a t i o n M o d e
A syn c hroni za tion pulse is fed fr om the base stat io n by p hysical con nection to the Sync B NC
connect or on the rear of the Test S et. The base st ation does no t nee d to be tr ansmitt ing t o car ry out
test ing usin g th e Pu lse Mode. T he sig nal ge nerat ed by the Test Set is t imed t o pr ovide co rre ct
synchron ization wi th t he ba se stat ion syn ch roniza tion pulse.
T h e T 1 S i g n a l ge n e r a t e d b y t h e T e s t S e t m u s t u s e t h e s a m e M C C - M N C - B C C v a l u e s f o r
s cr a m b l i n g a s t h e b a s e s t a t i o n u n d e r t e s t . I f t h e r e i s n o b a s e s t a t i o n T x s i g n a l , t h e s e v a l u e s
m us t b e e n t e r e d m a n u a l l y o n t h e
The Sync Pulse Offset par amete r r epr esents the offse t be twe en t he st art of fr ame 1, time sl ot 1 of the
base st ation' s down link fr ame str uctur e and the synch roniza tion p ulse. R ange is 0 t o 1,02 0,000 µ s.
For example, a value o f 10 µ s indicat es th at t he ba se stat ion's syn ch roniza tion pulse o ccurs 1 0 µ s
aft er t he st art of fra me 1, timeslot 1 of t he ba se stat ion's d ownl ink fr ame st ruct ure.
The Sync P ulse E dge paramet er selects whet her timing is re fer enced t o th e risi ng or fal ling e dge of
the base st ation 's synchr onizatio n pulse .
Pu ls e S p e ci fi c ati o n
The signal applied to the Sync B NC C onne ct or on t he r ear of t he T est S et should confor m to the
specifi ca tions shown below .
Logic 1 Level
Logic 0 Level
P ulse Wi dth
Pulse Pol arit y
I nput Resist ance
T E T R A B S T 1 S y s t e m
TE TR A B S T1 S ystem I D and S ync Conf igur ation Tile
+3. 85 to +5. 00 V (max) †
0 ( m in)† to 1.35 V
> 1. 0 µs
Risin g or Fal ling
1 0 k Ω ± 5%
T h e v o lt a g e o n t h i s c o n n e c t o r s h o u ld a t n o t i m e e x c e e d + 5 . 0 V o r b e a l l o w e d t o
g o n e g a t i v e .
ile, t h e T 1 U p l i n k S i g n a l g e n e r a t e d b y t h e T e s t S e t
8-4
TE TRA B S T1
.