mobiluri telekomunikaciis miwispira da Tanamgzavruli sistemebi

ganmeorebis N periodis mqone fsevdo-SemTxveviTi
mimdevrobis nebismieri r sigrZis CamonaWeri,
romelic Sedgeba `+1~ an `-1~ elementebisagan, mimdevrobaSi
warmoiqmneba saSualod N-jer;
aseTi mimdevrobebis avtokorelaciuri da urTierTkorelaciuri
funqciebi uzrunvelyofen optimalur
korelaciur gadamuSavebas miRebis dros.
signalis bazis gafarToebis princi pi sixSiris
speqtris pirdapiri gafarToebis meTodiT SeiZleba
aixsnas nax.1.10-is b,g,d fragmentis meSveobiT, sadac
erTeuli biti Seesabameba `+1~ elements, xolo
nulovani _ `-1~ elements.
b)
g)
d)
e)
a)
v)
1
0
1
0
1
0
informaciuli
signal i D(t)
D(t)
S(t)
S(t) D(t)
U(t)
V(t)
1
-1
T
Kkoduri mimdevroba
S(t)
nax. 1.10. sixSiris pirdapiri gafarToebis meTodi
a) koduri modulatori;
b) informaciuli signali;
g) koduri mimdevroba;
d) kodiT mani pulirebuli informaciuli
signali;
e) fazamani pulirebuli rTuli signali ;
v) kompleqsuri fazamani pulirebuli signali .
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rTuli signali
S(t) D(t)
2T 3T
t
t
t
t
t
gadamcemis gamosasvlelze fazamanipulirebuli
U(t) signali warmoadgens radioimpulsebis mimdevrobas,
romelTa sawyisi fazebi (0 da 180) icvleba
mocemuli kanoniT.
gadamtani f 0 sixSiris diskretuli signali kompleqsur
formaSi SeiZleba warmodgenil iqnas ase:
Re [ S
{t} exp(j 2π f t)] ,
S{t} 0
sadac
S
{t}
i
a
S
i 0(t
iΔ)
aris diskretuli sig-
nalis kompleqsuri momvlebi.
signalis i-uri impulsis kompleqsuri amplituda:
a i a
i exp[ j arg( a
i )] ,
sadac a i da arg( a
i)
Sesabamisad diskretuli sig-
nalis i-uri impulsis namdvili amplituda da sawyisi
fazaa; S o(t i)
- standartuli radioimpulsis
kompleqsuri momvlebia.
{a i }={a: i=…,-1,0,1,…} mimdevrobas ewodeba koduri
mimdevroba anu kodi.
Tu kodur mimdevrobas aqvs gameorebis N periodi
(a= a, i=…,-1,0,1,…), maSin S{t}-s ewodeba perioduli
diskretuli signali, xolo N ricxvs _kodis sigrZe.
nebismieri perioduli diskretuli signali
(pds) SeiZleba miviRoT, impulsuri finituri N signalis
gameorebiT T=N periodiT, amitom pds-saTvis
marTebulia Semdegi toloba:
N1
S{t}= a S
i 0t
i rNΔ
r i0
diskretul signals, romlis koduri mimdevroba
binaluria (a i =0,1,…,N-1, anu icvleba sawyisi fazebi,
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