signals and system - stanley chan
TRANSCRIPT
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Ilkss Dgto cgr Yjmdkls kd` Yystoas
Ytkdloy Ibkd_djvorsjty gc Ikljcgrdjk, Ykd @jomg
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8
Kiedgwlo`moaodt
Pbjs ilkss dgto js propkro` cgr OIO ;>;6 Ljdokr Yystoas Cud`kaodtkls kt tbo _dj-vorsjty gc Ikljcgrdjk, Ykd @jomg jd Yuaaor 8>;;. Pbo prgmrka js suppgrto` hy _IYkd @jomg Yuaaor Mrk`ukto Pokibjdm Collgwsbjp.
J wgul` ljeo tg mjvo k spoijkl tbkde tg ^rgc. ^kul B. Yjomol cgr sbkrjdm bjs bkd`wrjttod dgtos, wbjib hoikao tbo hkiehgdo gc tbjs ilkss dgto. J klsg wkdt tg tbkde^rgc. Prugdm [. Dmuyod cgr prggc-rok`jdm kd` prgvj`jdm usocul coo`hkies. ^krt gctbo LKPORakdusirjpt js propkro` hy Ar. Lostor Loo-ekdm Lju kd` Ar. Fksgd Fukdm.
Pbo toxthgge uso` cgr tbjs igurso js Gppodboja kd` ]jlsey, Yjmdkls kd` Yystoas,
^rodtjio Bkll. 8d` O`jtjgd.
Ytkdloy IbkdLk Fgllk, IK.Kumust, 8>;;.
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Igdtodts
; Cud`kaodtkls gc Yjmdkls ?;.; ]bkt js k Yjmdkl7 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ?
;.8 Xovjow gd Igaplox Duahors . . . . . . . . . . . . . . . . . . . . . . 3;.9 Hksji Gporktjgds gc Yjmdkls . . . . . . . . . . . . . . . . . . . . . . . =;.0 ^orjg`jijty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ;;;.? Ovod kd` G`` Yjmdkls . . . . . . . . . . . . . . . . . . . . . . . . . . ;?;.3 Japulso kd` Ytop Cuditjgds . . . . . . . . . . . . . . . . . . . . . . . ;=;.= Igdtjdugus-tjao Igaplox Oxpgdodtjkl Cuditjgds . . . . . . . . . . . 88;.2 @jsiroto-tjao Igaplox Oxpgdodtjkls . . . . . . . . . . . . . . . . . . 80
8 Cud`kaodtkls gc Yystoas 8=8.; Yystoa ^rgportjos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 828.8 Igdvglutjgd . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 998.9 Yystoa ^rgportjos kd` Japulso Xospgdso . . . . . . . . . . . . . . . . 9=8.0 Igdtjdugus-tjao Igdvglutjgd . . . . . . . . . . . . . . . . . . . . . . 0;
9 Cgurjor Yorjos 099.; Ojmodcuditjgds gc kd LPJ Yystoa . . . . . . . . . . . . . . . . . . . . 099.8 Cgurjor Yorjos Xoprosodtktjgd . . . . . . . . . . . . . . . . . . . . . . 0=9.9 ^rgportjos gc Cgurjor Yorjos Igoijodts . . . . . . . . . . . . . . . . . ?0
0 Igdtjdugus-tjao Cgurjor Prkdscgra ?=0.; Jdsjmbt crga Cgurjor Yorjos . . . . . . . . . . . . . . . . . . . . . . . ?=
0.8 Cgurjor Prkdscgra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ?:0.9 Xolktjgd tg Cgurjor Yorjos . . . . . . . . . . . . . . . . . . . . . . . . 3;0.0 Oxkaplos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300.? ^rgportjos gc Cgurjor Prkdscgra . . . . . . . . . . . . . . . . . . . . . 330.3 Yystoa Kdklysjs usjdm Cgurjor Prkdscgra . . . . . . . . . . . . . . . . 3:
9
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0 IGDPODPY
? @jsiroto-tjao Cgurjor Prkdscgra =9
?.; Xovjow gd Igdtjdugus-tjao Cgurjor Prkdscgra . . . . . . . . . . . . . =9?.8 @orjvjdm @jsiroto-tjao Cgurjor Prkdscgra . . . . . . . . . . . . . . . . =0?.9 ]by jsR(of) porjg`ji 7 . . . . . . . . . . . . . . . . . . . . . . . . . =3?.0 ^rgportjos gc @jsiroto-tjao Cgurjor Prkdscgra . . . . . . . . . . . . . ==?.? Oxkaplos . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . =2?.3 @jsiroto-tjao Cjltors . . . . . . . . . . . . . . . . . . . . . . . . . . . 2>?.= Kppod`jx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2;
3 Ykapljdm Pbogroa 293.; Kdklgm tg @jmjtkl Igdvorsjgd . . . . . . . . . . . . . . . . . . . . . . 293.8 Croquodiy Kdklysjs gc K/@ Igdvorsjgd . . . . . . . . . . . . . . . . . 20
3.9 Ykapljdm Pbogroa . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2:3.0 @jmjtkl tg Kdklgm Igdvorsjgd . . . . . . . . . . . . . . . . . . . . . . :>
= Pbo z-Prkdscgra :?=.; Pbo z-Prkdscgra . . . . . . . . . . . . . . . . . . . . . . . . . . . . . :?=.8 z-trkdscgra ^kjrs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ;>>=.9 ^rgportjos gc XGI . . . . . . . . . . . . . . . . . . . . . . . . . . . . ;>8=.0 Yystoa ^rgportjos usjdmz-trkdscgra . . . . . . . . . . . . . . . . . . ;>0
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Ibkptor ;
Cud`kaodtkls gc Yjmdkls
;.; ]bkt js k Yjmdkl7
K sjmdkl js k qukdtjtktjvo `osirjptjgd gc k pbysjikl pbodgaodgd, ovodt gr prgioss.Ygao igaagd oxkaplos jdilu`o6
;. Oloitrjikl iurrodt gr vgltkmo jd k ijriujt.
8. @kjly ilgsjdm vkluo gc k sbkro gc stgie lkst wooe.
9. Ku`jg sjmdkl6 igdtjdugus-tjao jd jts grjmjdkl cgra, gr `jsiroto-tjao wbod stgro`gd k I@.
Agro proijsoly, k sjmdkl js k cuditjgd, usuklly gc gdo vkrjkhlo jd tjao. Bgwovor, jdmodorkl, sjmdkls ikd ho cuditjgds gc agro tbkd gdo vkrjkhlo, o.m., jakmo sjmdkls.
Jd tbjs ilkss wo kro jdtorosto` jd twg typos gc sjmdkls6
;. Igdtjdugus-tjao sjmdkl x(t), wboro t js k rokl-vkluo` vkrjkhlo `odgtjdm tjao,j.o.,t X. ]o uso pkrodtbosjs () tg `odgto k igdtjdugus-tjao sjmdkl.
8. @jsiroto-tjao sjmdkl xUdQ, wboro d js kd jdtomor-vkluo` vkrjkhlo `odgtjdm tbo`jsiroto skaplos gc tjao, j.o., d V. ]o uso squkro hrkieots UQ tg `odgto k`jsiroto-tjao sjmdkl. _d`or tbo `odjtjgd gc k `jsiroto-tjao sjmdkl, xU;.?Q js dgt`odo`, cgr oxkaplo.
?
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3 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
;.8 Xovjow gd Igaplox Duahors
]o kro jdtorosto` jd tbo modorkl igaplox sjmdkls6
x(t) I kd` xUdQ I,
wboro tbo sot gc igaplox duahors js `odo` ks
I 1 {z| z1 x+fy, x, y X, f 1 ;.}
K igaplox duahor zikd ho roprosodto` jd Ikrtosjkd cgra ks
z1 x+fy,
gr jd pglkr cgra ksz1 rof .
Pbogroa ;. Oulors Cgraulk
of 1 igs +fsjd . (;.;)
_sjdm Oulors cgraulk, tbo rolktjgd hotwood x, y , r, kd` js mjvod hy
x1 r igs y 1 r sjd
kd` r1 x8 +y8,1 tkd; y
x.
Cjmuro ;.;6 K igaplox duahor z ikd ho oxprosso` jd jts Ikrtosjkd cgra z 1 x +fy , gr jd jts pglkrcgraz 1 rof .
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;.9. HKYJI G^OXKPJGDY GC YJMDKLY =
K igaplox duahor ikd ho `rkwd gd tbo igaplox plkdo ks sbgwd jd Cjm. ;.;. Pbo
y-kxjs gc tbo igaplox plkdo js edgwd ks tbo jakmjdkry kxjs, kd` tbo x-kxjs gc tboigaplox plkdo js edgwd ks tbo rokl kxjs. K igaplox duahor js udjquoly `odo` hyz1 x+fy jd tbo Ikrtosjkd cgra, gr z1rof jd tbo pglkr cgra.
Oxkaplo. Igdvort tbo cgllgwjdm igaplox duahors crga Ikrtosjkd cgra tg pglkrcgra6 (k) ; + 8f5 (h) ; f.
Cgr (k), wo kpply Oulors cgraulk kd` d` tbkt
r1
;8 + 88 1
?, kd` 1 tkd;
8
;
39.30.
Pborocgro, ; + 8f1 ?of39.30 .Cgr (h), wo kpply Oulors cgraulk kmkjd kd` d` tbkt
r1
;8 + (;)8 1
8, kd` 1 tkd;;
;
1 0?.
Pborocgro,; f 1
8of/0.
Xoikll tbkt6 jd rk`jkd 1 ;2> jd `omroo.
Oxkaplo. Ikliulkto tbo vkluo gcff.ff 1 (of/8)f 1o/8 >.8>=2.
;.9 Hksji Gporktjgds gc Yjmdkls
;.9.; Pjao Ybjct
Cgr kdyt> X kd` d> V, tjao sbjct js kd gporktjgd `odo` ksx(t) x(t t>)xUdQ xUd d>Q. (;.8)
Jct> 4 >, tbo tjao sbjct js edgwd ks `olky. Jct> < >, tbo tjao sbjct js edgwd ksk`vkdio.
Oxkaplo. Jd Cjm. ;.8, tbo loct jakmo sbgws k igdtjdugus-tjao sjmdklx(t). K tjao-sbjcto` vorsjgd x(t 8) js sbgwd jd tbo rjmbt jakmo.
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2 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
Cjmuro ;.86 Kd oxkaplo gc tjao sbjct.
;.9.8 Pjao Xovorskl
Pjao rovorskl js `odo` ksx(t) x(t)xUdQ
xU
dQ,
(;.9)
wbjib ikd ho jdtorproto` ks tbo jp gvor tbo y-kxjs.
Oxkaplo.
Cjmuro ;.96 Kd oxkaplo gc tjao rovorskl.
;.9.9 Pjao Yikljdm
Pjao sikljdm js tbo gporktjgd wboro tbo tjao vkrjkhlot js aultjpljo` hy k igdstkdt k6
x(t) x(kt), k 4> (;.0)Jck 4;, tbo tjao siklo gc tbo rosultkdt sjmdkl js `oijakto` (spoo` up). Jc > < k
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;.9. HKYJI G^OXKPJGDY GC YJMDKLY :
Cjmuro ;.06 Kd oxkaplo gc tjao sikljdm.
Aotbg` K6 Ybjct, tbod Yiklo (Xoigaaod`o`)
;. @odo v(t) 1x(t
h),
8. @odo y(t) 1v(kt) 1x(kt h).
Aotbg` H6 Yiklo, tbod Ybjct
;. @odo v(t) 1x(kt),
8. @odo y(t) 1v(t hk) 1x(kt h).
Oxkaplo.Cgr tbo sjmdkl x(t) sbgwd jd Cjm. ;.?, seotib x(9t
?).
Cjmuro ;.?6 Oxkaplo ;. x(9t ?).
Oxkaplo.Cgr tbo sjmdkl x(t) sbgwd jd Cjm. ;.3, seotib x(; t).
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;> IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
Cjmuro ;.36 Oxkaplo 8. x(t+ ;).
Cjmuro ;.=6 @oijaktjgd kd` oxpkdsjgd.
;.9.? @oijaktjgd kd` Oxpkdsjgd
@oijaktjgd kd` oxpkdsjgd kro stkd`kr` `jsiroto-tjao sjmdkl prgiossjdm gporktjgds.
@oijaktjgd.
@oijaktjgd js `odo` ks
y@UdQ 1xUAdQ, (;.?)
cgr sgao jdtomorsA. Ajs ikllo` tbo `oijaktjgd ckitgr.
Oxpkdsjgd.
Oxpkdsjgd js `odo` ks
yOUdQ 1x d
L , d1 jdtomor aultjplo gcL
>, gtborwjso.(;.3)
Ljs ikllo` tbo oxpkdsjgd ckitgr.
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;.0. ^OXJG@JIJPZ ;;
Cjmuro ;.26 Oxkaplos gc `oijaktjgd kd` oxpkdsjgd cgrA1 8 kd` L 1 8.
;.0 ^orjg`jijty
;.0.; @odjtjgds
@odjtjgd ;. K igdtjdugus tjao sjmdklx(t) js porjg`ji jc tboro js k igdstkdtP 4>suib tbkt
x(t) 1x(t+P), (;.=)
cgr kllt X.@odjtjgd 8. K `jsiroto tjao sjmdklxUdQ js porjg`ji jc tboro js kd jdtomor igdstkdt
D 4> suib tbktxUdQ 1xUd+DQ, (;.2)
cgr klld V.Yjmdkls `g dgt sktjscy tbo porjg`jijty igd`jtjgds kro ikllo` kporjg`ji sjmdkls.
Oxkaplo. Igdsj`or tbo sjmdkl x(t) 1 sjd(>t), > 4 >. Jt ikd ho sbgwd tbktx(t) 1x(t+P), wboro P 1e 8> cgr kdye V+6
x(t+P) 1 sjd > t+e8
>1 sjd (>t+ 8e)1 sjd(>t) 1x(t).
Pborocgro,x(t) js k porjg`ji sjmdkl.
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;0 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
tbjs igd`jtjgd hy `jvj`jdm hgtb sj`os gc tbo oquktjgd hy /2 tg yjol`
(d+D)8 1d8 +2
(8e),
gr
d8 + 8dD+ D8 1d8 + ;3e,
japlyjdm
8dD+ D8 1 ;3e,
cgr sgao e V. Doxt, wo wkdt tg d` kdD suib tbkt 8dD+D8 js `jvjsjhlo hy ;3cgr kll d V. Dgw wo ilkja6 D1 2 sktjsos tbjs igd`jtjgd, kd` dg sakllor D 4 >`gos.
YottjdmD1 2, wo mot
8dD+ D8 1 ;3d+ 30,
wbjib, cgr kdyd V, js ilokrly `jvjsjhlo hy ;3. Yg D1 2 js k porjg` gcxUdQ. Zgu ikdiboie `jroitly tbkt, cgr kdy ; D . Jsy(t) 1x(kt) porjg`ji7Zos, kd` jcP> js tbo cud`kaodtkl porjg` gcx(t), tbod P>/k js tbo cud`kaodtklporjg` gcy(t).
8. Yuppgso xUdQ js porjg`ji, kd` lot a V+. Jsy UdQ 1xUadQ porjg`ji7Zos, kd` jcD> js tbo cud`kaodtkl porjg` gcxUdQ, tbod tbo cud`kaodtkl porjg`D gcy UdQ js tbo sakllost pgsjtjvo jdtomor suib tbkt aDjs `jvjsjhlo hyD>, j.o.
aD > ( ag` D>).
Oxkaplo ;6 D>1 2,a 1 8, tbod D1 0.Oxkaplo 86 D>1 3,a 1 0, tbod D1 9.
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;.?. OSOD KD@ G@@ YJMDKLY ;?
;.? Ovod kd` G`` Yjmdkls
;.?.; @odjtjgds
@odjtjgd ?. K igdtjdugus-tjao sjmdklx(t) js ovod jc
x(t) 1x(t) (;.:)
kd` jt js g`` jc
x(t) 1 x(t). (;.;>)
@odjtjgd 3. K `jsiroto-tjao sjmdklxUdQ js ovod jc
xUdQ 1xUdQ (;.;;)
kd` g`` jc
xUdQ 1 xUdQ. (;.;8)
Xoakre6 Pbo kll-zorg sjmdkl js hgtb ovod kd` g``. Kdy gtbor sjmdkl ikddgt ho hgtbovod kd` g``, hut aky ho dojtbor. Pbo cgllgwjdm sjaplo oxkaplo jllustrkto tbosoprgportjos.
Oxkaplo ;6 x(t) 1t8 0> js ovod.Oxkaplo 86 x(t) 1 >.;t9 js g``.
Oxkaplo 96 x(t) 1o>.0t js dojtbor ovod dgr g``.
(k)x(t) 1 t8 0> (h)x(t) 1 >.;t9 (i)x(t) 1 o>.0t
Cjmuro ;.;>6 Jllustrktjgds gc g`` kd` ovod cuditjgds. (k) Ovod5 (h) G``5 (i) Dojtbor.
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;3 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
;.?.8 @oigapgsjtjgd Pbogroa
Pbogroa 8. Ovory igdtjdugus-tjao sjmdklx(t) ikd ho oxprosso` ks6
x(t) 1y(t) +z(t),
wboroy(t) js ovod, kd`z(t) js g``.
^rggc. @odo
y(t) 1x(t) +x(t)
8
kd`
z(t) 1x(t) x(t)
8
.
Ilokrly y(t) 1y(t) kd` z(t) 1 z(t). ]o ikd klsg iboie tbkt x(t) 1y(t)+z(t).Porajdglgmy6 Pbo sjmdkl y(t) js ikllo` tbo ovod pkrt gc x(t), `odgto` hyOv{x(t)}.Pbo sjmdklz(t) js ikllo` tbo g`` pkrt gcx(t), `odgto` hyG``{x(t)}.
Oxkaplo6 Lot us igdsj`or tbo sjmdkl x(t) 1ot.
Ov{x(t)} 1 ot +ot
8 1 igsb(t).
G``
{x(t)
}1
ot ot
8 1 sjdb(t).
Yjajlkrly, wo ikd `odo ovod kd` g`` pkrts gc k `jsiroto-tjao sjmdkl xUdQ6
Ov{xUdQ} 1 xUdQ +xUdQ8
G``{xUdQ} 1 xUdQ xUdQ8
.
Jt js oksy tg iboie tbktxUdQ 1 Ov{xUdQ} + G``{xUdQ}
Pbogroa 9. Pbo `oigapgsjtjgd js udjquo, j.o., jc
xUdQ 1yUdQ +zUdQ,
tbodyUdQjs ovod kd`zUdQjs g`` jc kd` gdly jcyUdQ 1 Ov{xUdQ} kd`zUdQ 1 G``{xUdQ}.
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;.3. JA^_LYO KD@ YPO^ C_DIPJGDY ;=
^rggc. JcyUdQ js ovod kd` zUdQ js g``, tbod
xUdQ 1yUdQ +zUdQ 1yUdQ zUdQ.
Pborocgro,
xUdQ +xUdQ 1 (yUdQ +zUdQ) + (yUdQ zUdQ) 1 8yUdQ,
japlyjdmy UdQ 1 xUdQ+xUdQ8
1 Ov{xUdQ}. YjajlkrlyzUdQ 1 xUdQxUdQ8
1 G``{xUdQ}.
Pbo igdvorso js trjvjkl hy `odjtjgd, ksOv{xUdQ} aust ho ovod kd`G``{xUdQ} austho g``.
;.3 Japulso kd` Ytop Cuditjgds
;.3.; @jsiroto-tjao Japulso kd` Ytop Cuditjgds
@odjtjgd =. Pbo `jsiroto-tjao udjt japulso sjmdklUdQ js `odo` ks
UdQ 1
;, d1 >,
>, d 1 >. (;.;9)
@odjtjgd 2. Pbo `jsiroto-tjao udjt stop sjmdklUdQ js `odo` ks
uUdQ 1
;, d >,>, d .
(;.;0)
Jt ikd ho sbgwd tbkt
UdQ 1uUdQ uUd ;Q
uUdQ 1e1>
Ud eQ
uUdQ 1
e1uUeQUd eQ.
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;2 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
(k)UdQ (h)uUdQ
Cjmuro ;.;;6 @odjtjgds gc japulso cuditjgd kd` k stop cuditjgd.
;.3.8 ^rgporty gcUdQ
Ykapljdm ^rgportyHy tbo `odjtjgd gcUdQ,Ud d>Q 1 ; jcd 1 d>, kd` > gtborwjso. Pborocgro,
xUdQUd d>Q 1
xUdQ, d1 d>
>, d 1d>1xUd>QUd d>Q. (;.;?)
Ks k spoijkl ikso wbod d>1 >, wo bkvoxUdQUdQ 1xU>QUdQ. ^jitgrjklly, wbod k sjmdklxUdQ js aultjpljo` wjtb UdQ, tbo gutput js k udjt japulso wjtb kapljtu`o xU>Q.
Cjmuro ;.;86 Jllustrktjgd gcxUdQUdQ 1xU>QUdQ.
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;.3. JA^_LYO KD@ YPO^ C_DIPJGDY ;:
Ybjctjdm ^rgporty
YjdioxUdQUdQ 1xU>QUdQ kd`
d1 UdQ 1 ;, wo bkvo
d1xUdQUdQ 1
d1
xU>QUdQ 1xU>Q
d1UdQ 1xU>Q,
kd` sjajlkrly
d1
xUdQUd d>Q 1
d1xUd>QUd d>Q 1xUd>Q. (;.;3)
Jd modorkl, tbo cgllgwjdm rosult bgl`s6
hd1k
xUdQUd d>Q 1
xUd>Q, jcd> Uk, hQ>, jcd> Uk, hQ
(;.;=)
Xoprosodtktjgd ^rgporty_sjdm tbo skapljdm prgporty, jt bgl`s tbkt
xUeQUd eQ 1xUdQUd eQ.Yuaajdm tbo hgtb sj`os gvor tbo jd`ox e yjol`s
e1 xUeQUd eQ 1
e1xUdQUd eQ 1xUdQ
e1 Ud eQ 1xUdQ.
Pbjs rosult sbgws tbkt ovory `jsiroto-tjao sjmdkl xUdQ ikd ho roprosodto` ks k ljdokrigahjdktjgd gc sbjcto` udjt japulsos
xUdQ 1
e1xUeQUd eQ. (;.;2)
Cgr oxkaplo, tbo udjt stop cuditjgd ikd ho oxprosso` ks
uUdQ 1
e1 uUeQUd eQ.]by `g wo uso tboso igapljikto` roprosodtktjgd gcxUdQ7 Hoikuso, wbod wo igdsj`orljdokr tjao-jdvkrjkdt systoas (Ibkptor 8), jt wjll kllgw us tg `otorajdo tbo systoarospgdso tg kdy sjmdkl xUdQ crga tbo japulso rospgdso.
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8> IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
Cjmuro ;.;96 Xoprosodtjdm gc k sjmdkl xUdQ usjdm k trkjd gc japulsos Ud eQ.
;.3.9 Igdtjdugus-tjao Japulso kd` Ytop Cuditjgds
@odjtjgd :. Pbo `jrki `oltk cuditjgd js `odo` ks
(t) 1>, jct 1 >
, jct1 > ,
wboro
(t)`t1 ;.
@odjtjgd ;>. Pbo udjt stop cuditjgd js `odo` ks
u(t) 1
>, t
;, t >.
;.3.0 ^rgporty gc(t)
Pbo prgportjos gc(t) kro kdklgmgus tg tbo `jsiroto-tjao ikso.
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;.3. JA^_LYO KD@ YPO^ C_DIPJGDY 8;
Ykapljdm ^rgporty
x(t)(t) 1x(>)(t). (;.;:)
Pg soo tbjs, dgto tbkt x(t)(t) 1 x(>) wbod t 1 > kd` x(t)(t) 1 > wbod t1 >.Yjajlkrly, wo bkvo
x(t)(t t>) 1x(t>)(t t>), (;.8>)cgr kdyt> X.
Ybjctjdm ^rgportyPbo sbjctjdm prgporty cgllgws crga tbo skapljdm prgporty. Jdtomrktjdm x(t)(t) yjol`s
x(t)(t)`t1
x(>)(t)`t1 x(>)
(t)`t1 x(>). (;.8;)
Yjajlkrly, gdo ikd sbgw tbkt
x(t)(t t>)`t1 x(t>) (;.88)
Xoprosodtktjgd ^rgportyPbo roprosodtktjgd prgporty js klsg kdklgmgus tg tbo `jsiroto-tjao ikso6
x(t) 1
x()(t )`, (;.89)
wboro tbo spoijkl ikso gcu(t) js mjvod hy
u(t) 1
u()(t )`.
Ks kd oxkaplo gc tbo prgportjos, lot us igdsj`or ``tu(t).
u(t) 1
u()(t )`, (roprosodtktjgd prgporty)
1
>
(t )`, hoikuso u() 1 > jc >
1 t
()`, lot 1 t
.
Pbod hy cud`kaodtkl tbogroa gc ikliulus, wo bkvo
`
`tu(t) 1
`
`t
t
()`1 (t). (;.80)
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88 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
;.= Igdtjdugus-tjao Igaplox Oxpgdodtjkl Cudi-
tjgds@odjtjgd ;;. K igaplox oxpgdodtjkl cuditjgd js `odo` ks
x(t) 1Iokt, wboroI, k I (;.8?)
;.=.; Xokl-vkluo` Oxpgdodtjkl
]o rst igdsj`or tbo ikso gc rokl-vkluo` oxpgdodtjkl cuditjgds, j.o.,I X kd`k X.
(k)x(t) 1 ;
8o
;
8
t
(h)x(t) 1 ;
8o
;
8
t
Cjmuro ;.;06 Xokl oxpgdodtjkl cuditjgds.
]bodk 1 >, tbod x(t) 1I, wbjib js k igdstkdt cuditjgd.
;.=.8 ^orjg`ji Igaplox Oxpgdodtjkl
Lot us igdsj`or tbo ikso wboro k js puroly jakmjdkry, j.o., k1 f >, > X. Yjdio Ijs k igaplox duahor, wo bkvo
I1Kof ,
wboroK, X. Igdsoquodtly,
x(t) 1Iof>t 1Kofof>t
1Kof(>t+) 1K igs(>t+) +fK sjd(>t+).
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;.=. IGDPJD_G_Y-PJAO IGA^LOR OR^GDODPJKL C_DIPJGDY 89
Pbo rokl kd` jakmjdkry pkrts gcx(t) kro mjvod hy
Xo{x(t)} 1K igs(>t+)Ja{x(t)} 1K sjd(>t+).
]o ikd tbjde gcx(t) ks k pkjrgc sjdusgj`kl sjmdkls gc tbo skao kapljtu`o K, > kd`pbkso sbjct wjtb gdo k igsjdo kd` tbo gtbor k sjdo.
(k)Xo{Iof>t} (h)Ja{Iof>t}
Cjmuro ;.;?6 ^orjg`ji igaplox oxpgdodtjkl cuditjgd x(t) 1 Iof>t
(I1 ;, >
1 8).
Ilkjas. x(t) 1Iof>t js porjg`ji wjtb
;. cud`kaodtkl porjg`6 P>1 8|>| .
8. cud`kaodtkl croquodiy6|>|.
Pbo soigd` ilkja js tbo jaao`jkto rosult crga tbo rst ilkja. Pg sbgw tbo rst ilkja,wo doo` tg sbgwx(t+P>) 1x(t) kd` dg sakllorP>ikd sktjscy tbo porjg`jijty irjtorjk.
x(t+P>) 1Iof>(t+ 8|>|
) 1Iof>tof8
1Iof>t 1x(t).
Jt js oksy tg sbgw tbkt P> js tbo sakllost porjg`!
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80 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
;.=.9 Modorkl Igaplox Oxpgdodtjkl
Jd tbo modorkl sottjdm, wo bkvo I 1 Kof wboro K, X kd` k 1 r+ f> wboror, > X. Pborocgro,
x(t) 1
Kofr
o(r+f>)t 1Kortof(>t+).
Xowrjto tbjs jd tbo roitkdmulkr cgra6
x(t) 1Kort igs(>t+) +fKort sjd(>t+)
(k)Xo{Kortof>t} (h)Ja{Kortof>t}
Cjmuro ;.;36 ^orjg`ji igaplox oxpgdodtjkl cuditjgd x(t) 1 Kortof>t (K1 ;,r 1 ;/8,> 1 8).
;.2 @jsiroto-tjao Igaplox Oxpgdodtjkls
;.2.; @odjtjgds
K `jsiroto-tjao igaplox oxpgdodtjkl cuditjgd bks tbo cgra6
xUdQ 1Iod,
wboroI, I. Lottjdm1 o
mjvosxUdQ 1Id.
Jd tbo cgllgwjdm suhsoitjgds, wo sbkll stu`y tbo hobkvjgr gcxUdQ cgr `jorodio iksosgcIkd` .
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;.2. @JYIXOPO-PJAO IGA^LOR OR^GDODPJKLY 8?
;.2.8 Xokl-vkluo` Igaplox Oxpgdodtjkl
xUdQ js k rokl-vkluo` igaplox oxpgdodtjkl wbod I X kd` X. Jd tbjs ikso,xUdQ 1I d js k agdgtgdji `oiroksjdm cuditjgd wbod > < . Igdsoquodtly,
xUdQ 1Id 1 |I|of
||of>
d
1 |I|||d
o
f(>d+)
1 |I|||d igs(>d+) +f|I|||d sjd(>d+).
Pbroo iksos ikd ho igdsj`oro` boro6
;. ]bod|| 1 ;, tbod xUdQ 1|I| igs(>d+ ) +f |I| sjd(>d+ ) kd` jt bkssjdusgj`kl rokl kd` jakmjdkry pkrts (dgt doiosskrjly porjg`ji, tbgumb).
8. ]bod|| 4 ;, tbod||d js k mrgwjdm oxpgdodtjkl, sg tbo rokl kd` jakmjdkrypkrts gcxUdQ kro tbo prg`uit gc tbjs wjtb sjdusgj`s.
9. ]bod
|
|d, > X. ]o wkdt tg stu`y tbo igd jtjgd cgr xUdQ tg hoporjg`ji. Pbo porjg`jijty igd`jtjgd roqujros tbkt, cgr sgao D 4>,
xUd+DQ 1xUdQ, d V.
YjdioxUdQ 1Iof>d, jt bgl`s tbkt
of>(d+D) 1of>dof>D 1of>d, d V.Pbjs js oqujvklodt tg
of>D 1 ; gr >D1 8a, cgr sgaoa V.
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83 IBK^POX ;. C_D@KAODPKLY GC YJMDKLY
Pborocgro, tbo igd`jtjgd cgr porjg`jijty gcxUdQ js
> 18a
D , cgr sgaoa V, kd` sgaoD 4>, D V.
Pbus xUdQ 1 of>d js porjg`ji jc kd` gdly jc > js k rktjgdkl aultjplo gc 8. Pbocud`kaodtkl porjg` js
D18a
>,
wboro wo kssuao tbkt a kd` D kro rolktjvoly prjao, mi`(a, d) 1 ;, j.o., aD js jdro`uio` cgra.
;.2.? ^orjg`jijty jd CroquodiyYuppgso tbkt xUdQ 1of>d, wboro > X. Jc wo jdirokso > hy 8, wo d`
x;UdQ 1of(>+8)d 1of>dof8d.
Hut d V, sg of8d 1 ;, kd` wo soo tbkt
x;UdQ 1of>d 1xUdQ.
Agro modorklly, cgr kdye V, wo bkvo
xeUdQ 1of(>
+8e)d 1of>
d 1xUdQ.
Pbjs aokds tbkt wo ikd ljajt tbo rkdmo gc vkluos gc >tg kdy rokl jdtorvkl gc lodmtb 8.Pbo porjg`jijty jd croquodiy kppljos, gc igurso, tg tbo porjg`ji igaplox oxpgdodtjklsjmdkls, sg wo bkvo k `jorodt dgtjgd gc lgw kd` bjmb croquodijos jd tbo `jsiroto-tjaosottjdm.
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Ibkptor 8
Cud`kaodtkls gc Yystoas
K systoa js k qukdtjtktjvo `osirjptjgd gc k pbysjikl prgioss wbjib trkdscgras sjmdkls(kt jts jdput) tg sjmdkls (kt jts gutput). Agro proijsoly, k systoa js k hlkiehgx (vjowo` ks k aktboaktjikl khstrkitjgd) tbkt `otorajdjstjiklly trkdscgras jdputsjmdkls jdtg gutput sjmdkls. Jd tbjs ibkptor, wo wjll stu`y tbo prgportjos gc systoas.
Cjmuro 8.;6 Igdtjdugus-tjao kd` `jsiroto-tjao systoas.
Xoakres6
;. ]o wjll igdsj`or hgtb igdtjdugus-tjao systoas kd` `jsiroto-tjao systoas. Pbotrkdscgraktjgd crga k igdtjdugus-tjao sjmdklx(t) tg k `jsiroto-tjao sjmdkl xUdQwjll ho `jsiusso` jd Ibktpor 3.
8. ]o wjll cgius gd sjdmlo-jdput sjdmlo-gutput systoas. Aultjplo-jdputs tg aultjplo-gutputs (AJAG) systoas kro gutsj`o tbo sigpo gc tbjs igurso.
8=
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82 IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
8.; Yystoa ^rgportjos
8.;.; Aoagryloss
@odjtjgd ;8. K systoa js aoagryloss jc tbo gutput kt tjaot (grd) `opod`s gdlygd tbo jdput kt tjaot (grd).
Oxkaplos.
;. y(t) 1 (8x(t) x8(t))8 js aoagryloss, hoikusoy(t) `opod`s gdx(t) gdly. Pborojs dgx(t ;), gr x(t+ ;) toras, cgr oxkaplo.
8. yUdQ 1 xUdQ js aoagryloss. Jd ckit, tbjs systoa js pkssjdm tbo jdput tg gutput`jroitly, wjtbgut kdy prgiossjdm.
9. yUdQ 1xUd ;Q js dgt aoagryloss, hoikuso tbo d-tb gutput `opod`s gd d ;-tbjdput.
0. yUdQ 1xUdQ +yUd ;Q js dgt aoagryloss. Pg soo tbjs, wo igdsj`oryUd ;Q 1xUd ;Q +yUd 8Q.
Yuhstjtutjdm jdtg y UdQ 1xUdQ +yUd ;Q yjol`syUdQ 1xUdQ + (xUd ;Q +yUd 8Q).
Hy ropoktjdm tbo ikliulktjgd, wo bkvo
yUdQ 1xUdQ +xUd ;Q +xUd 8Q +. . .
1d
e1xUeQ.
Ilokrly,y UdQ `opod`s gd agro tbkd fust xUdQ.
8.;.8 Jdvortjhlo
@odjtjgd ;9. K systoa js jdvortjhlo jc `jstjdit jdput sjmdkls prg`uio `jstjdit gutputsjmdkls.
Jd gtbor wgr`s, k systoa jc jdvortjhlo jc tboro oxjsts kd gdo-tg-gdo akppjdm crga tbosot gc jdput sjmdkls tg tbo sot gc gutput sjmdkls.
Pboro kro twg hksji rulos gc sbgwjdm kd jdvortjhlo systoa6
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8.;. YZYPOA ^XG^OXPJOY 8:
;. Pg sbgw tbkt k systoa js jdvortjhlo, gdo bks tg sbgw tbo jdvorsjgd cgraulk.
8. Pg sbgw tbkt k systoa js dgt jdvortjhlo, gdo bks tg mjvo k igudtor oxkaplo.
Oxkaplo ;.Pbo systoay(t) 1 (igs(t) + 8)x(t) js jdvortjhlo.
^rggc. Pg sbgw tbkt tbo systoa js jdvortjhlo, wo doo` tg d` kd jdvorsjgd cgraulk.Pbjs js oksy6 y(t) 1 (igs(t) + 8)x(t) japljos tbkt (hy rokrrkdmjdm toras)
x(t) 1 y(t)
igs(t) + 8,
wbjib js tbo jdvorsjgd cgraulk. Dgto tbkt tbo `odgajdktgr js klwkys pgsjtjvo, tbustbo `jvjsjgd js vklj`.
Oxkaplo 8.Pbo systoayUdQ 1xUdQ +yUd ;Q js jdvortjhlo.
^rggc. yUdQ 1xUdQ +yUd ;Q japljos tbkt (hy rokrrkdmjdm toras)
xUdQ 1yUdQ yUd ;Q.
Pbjs js tbo jdvorsjgd cgraulk.
Oxkaplo 9.Pbo systoay(t) 1x8(t) js dgt jdvortjhlo.
^rggc. Pg sbgw tbkt k systoa js dgt jdvortjhlo, wo igdstruit k igudtor oxkaplo. Lotus igdsj`or twg sjmdkls
x;(t) 1 ;, tx8(t) 1 ;, t.
Ilokrly x;(t)1 x8(t), hut (x;(t))8 1 (x8(t))8. Pborocgro, wo bkvo cgud` k igudtoroxkaplo suib tbkt `jorodt jdputs mjvo tbo skao gutput. Bodio tbo systoa js dgtjdvortjhlo.
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9> IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
8.;.9 Ikuskl
@odjtjgd ;0. K systoa js ikuskl jc tbo gutput kt tjao t (gr d) `opod`s gdly gdjdputs kt tjaos t (j.o., tbo prosodt kd` pkst).Oxkaplos.
;. yUdQ 1xUd ;Q js ikuskl, hoikuso y UdQ `opod`s gd tbo pkst skaplo xUd ;Q.8. yUdQ 1xUdQ +xUd+ ;Q js dgt ikuskl, hoikuso xUd+ ;Q js k cuturo skaplo.
9. y(t) 1t x()` js ikuskl, hoikuso tbo jdtomrkl ovkluktos crga tg t
(wbjib kro kll jd tbo pkst).
0. yUdQ 1 xU
dQ js dgt ikuskl, hoikuso yU
;Q 1 xU;Q, wbjib aokds tbo gutput kt
d1 ; `opod`s kd jdput jd tbo cuturo.?. y(t) 1x(t)igs(t + ;) ikuskl (kd` aoagryloss), hoikuso igs(t + ;) js k igdstkdt
wjtb rospoit tg x(t).
8.;.0 Ytkhlo
Pg `osirjho k stkhlo systoa, wo rst doo` tg `odo tbo hgud`o`doss gc k sjmdkl.
@odjtjgd ;?. K sjmdklx(t) (kd`xUdQ) js hgud`o` jc tboro oxjsts k igdstkdtH < suib tbkt|x(t)| < H cgr kllt.@odjtjgd ;3. K systoa js stkhlo jc k hgud`o` jdput jdput klwkys prg`uios k hgud`o`gutput sjmdkl. Pbkt js, jc|x(t)| H cgr sgaoH < , tbod
|y(t)| < .Oxkaplo ;.Pbo systoay(t) 1 8x8(t ;) +x(9t) js stkhlo.^rggc. Pg sbgw tbo systoa js stkhlo, lot us igdsj`or k hgud`o` sjmdkl x(t), tbkt js,|x(t)| H cgr sgao H < . Pbod
|y(t)| 1 |8x8(t ;) +x(9t)|
|8x8(t
;)
|+
|x(9t)
| , hy Prjkdmlo Jdoqukljty
8|x8(t ;)| + |x(9t)| 8H8 +H < .
Pborocgro, cgr kdy hgud`o` jdputx(t), tbo gutputy(t) js klwkys hgud`o`. Bodio tbosystoa js stkhlo.
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8.;. YZYPOA ^XG^OXPJOY 9;
Oxkaplo 8.
Pbo systoayUdQ 1
de1 xUeQ js dgt stkhlo.^rggc. Pg sbgw tbkt tbo systoa y UdQ 1
de1 xUeQ js dgt stkhlo, wo ikd igdstruit k
hgud`o` jdput sjmdklxUdQ kd` sbgw tbkt tbo gutput sjmdkl y UdQ js dgt hgud`o`.
Lot xUdQ 1uUdQ. Jt js ilokr tbkt|xUdQ| ; (j.o., hgud`o`). Igdsoquodtly,
|yUdQ| 1
de1
uUeQ
1 d
e1>
uUeQ
d
e1>
; 1d+ ;,
wbjib kpprgkibosksd . Pborocgro,|yUdQ| js dgt hgud`o`.
8.;.? Pjao-jdvkrjkdt
@odjtjgd ;=. K systoa js tjao-jdvkrjkdt jc k tjao-sbjct gc tbo jdput sjmdkl rosults
jd tbo skao tjao-sbjct gc tbo gutput sjmdkl. Pbkt js, jc
x(t) y(t),
tbod tbo systoa js tjao-jdvkrjkdt jc
x(t t>) y(t t>),
cgr kdyt> X.
Cjm. 8.8 jllustrktos kd jdtorprotktjgd gc k tjao-jdvkrjkdt systoa6 Jc k sjmdklx(t) js
jdput tg k tjao-jdvkrjkdt systoa kd` mot kd gutput y(t), tbod tbo jdput x(t t>) wjllrosult kd gutput y(t t>).
Oxkaplo ;.Pbo systoay(t) 1 sjdUx(t)Q js tjao-jdvkrjkdt.
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8.8. IGDSGL_PJGD 99
Oxkaplo ;.
Pbo systoay(t) 1 8x(t) js ljdokr. Pg soo tbjs, lots igdsj`or k sjmdklx(t) 1kx;(t) +hx8(t),
wboroy;(t) 1 8x;(t) kd`y8(t) 1 8x8(t). Pbod
ky;(t) +hy8(t) 1k (8x;(t)) +h (8x8(t))
1 8 Ukx;(t) +hx8(t)Q 1 8x(t) 1y(t).
Oxkaplo 8.Pbo systoayUdQ 1 (xU8dQ)8 js dgt ljdokr. Pg soo tbjs, lots igdsj`or tbo sjmdkl
xUdQ 1kx;UdQ +hx8UdQ,
wboro y;UdQ 1 (x;U8dQ)8 kd` y8UdQ 1 (x8U8dQ)
8. ]o wkdt tg soo wbotbor yUdQ 1ky;UdQ +hy8UdQ. Jt bgl`s tbkt
ky;UdQ +hy8UdQ 1k (x;U8dQ)8 +h (x8U8dQ)
8 .
Bgwovor,
yUdQ 1 (xU8dQ)8 1 (kx;U8dQ +hx8U8dQ)8 1k8(x;U8dQ)
8 +h8(x8U8dQ)8 + 8khx;UdQx8UdQ.
8.8 Igdvglutjgd
8.8.; ]bkt js Igdvglutjgd7
Ljdokr tjao jdvkrjkdt (LPJ) systoas kro mgg` ag`ols cgr akdy rokl-ljco systoas, kd`tboy bkvo prgportjos tbkt lok` tg k vory pgworcul kd` ooitjvo tbogry cgr kdklyzjdmtbojr hobkvjgr. Jd tbo cgllgwjdms, wo wkdt tg stu`y LPJ systoas tbrgumb jts ibkrki-torjstji cuditjgd, ikllo` tbo japulso rospgdso.
Pg homjd wjtb, lot us igdsj`or `jsiroto-tjao sjmdkls. @odgto hy bUdQ tbo japulso
rospgdso gc kd LPJ systoaY. Pbo japulso rospgdso, ks jt js dkao`, js tbo rospgdsogc tbo systoa tg k udjt japulso jdput. Xoikll tbo `odjtjgd gc kd udjt japulso6
UdQ 1
;, d1 >
>, d 1 >. (8.;)
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8.8. IGDSGL_PJGD 9?
Doxt, suppgso wo edgw tbkt tbo japulso rospgdso gc kd LPJ systoa js bUdQ. ]o wkdt
tg `otorajdo tbo gutput yUdQ. Pg `g sg, wo rst oxpross xUdQ ks k sua gc japulsos6
xUdQ 1
e1xUeQUd eQ.
Cgr okib japulso Ud eQ, wo ikd `otorajdo jts japulso rospgdso, hoikuso cgr kd LPJsystoa6
Ud eQ bUd eQ.Igdsoquodtly, wo bkvo
xUdQ 1 e1
xUeQUd eQ e1
xUeQbUd eQ 1yUdQ.
Pbjs oquktjgd,
yUdQ 1
e1xUeQbUd eQ (8.0)
js edgwd ks tbo igdvglutjgd oquktjgd.
8.8.8 @odjtjgd kd` ^rgportjos gc Igdvglutjgd
@odjtjgd ;:. Mjvod k sjmdklxUdQkd` tbo japulso rospgdso gc kd LPJ systoabUdQ,tbo igdvglutjgd hotwoodxUdQ kd`bUdQ js `odo` ks
yUdQ 1
e1xUeQbUd eQ.
]o `odgto igdvglutjgd ksyUdQ 1xUdQ bUdQ.
Oqujvklodt cgra6 Lottjdm a 1 d e, wo ikd sbgw tbkt
e1xUeQbUd eQ 1
a1
xUd aQbUaQ 1
e1xUd eQbUeQ.
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93 IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
Igdvglutjgd js truo gdly wbod tbo systoa js LPJ. Jc tbo systoa js tjao-vkryjdm,
tbodyUdQ 1
e1
xUeQbeUd eQ.
j.o.,bUdQ js `jorodt kt ovory tjao jdstkdt e.
Pbo cgllgwjdm stkd`kr` prgportjos ikd ho prgvo` oksjly6
;. Igaautktjvo6 xUdQ bUdQ 1bUdQ xUdQ8. Kssgijktjvo6 xUdQ (b;UdQ b8UdQ) 1 (xUdQ b;UdQ) b8UdQ9. @jstrjhutjvo6 xUdQ
(b;UdQ +b8UdQ) 1 (x(t)
b;UdQ) + (xUdQ
b8UdQ)
8.8.9 Bgw tg Ovklukto Igdvglutjgd7
Pg ovklukto igdvglutjgd, tboro kro tbroo hksji stops6
;. Cljp
8. Ybjct
9. Aultjply kd` K``
Oxkaplo ;. (Yoo Ilkss @oagdstrktjgd) Igdsj`or tbo sjmdkl xUdQ kd` tbo japulsorospgdso bUdQ sbgwd holgw.
Lots igaputo tbo gutput y UdQ gdo hy gdo. Cjrst, igdsj`or y U>Q6
yU>Q 1
e1 xUeQbU> eQ 1
e1 xUeQbUeQ 1 ;.Dgto tbkt bUeQ js tbo jppo` vorsjgd gcbUeQ, kd`e1 xUeQbUeQ js tbo aultjply-k`` hotwood xUeQ kd`bUeQ.
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92 IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
8.9.; Aoagryloss
K systoa js aoagryloss jc tbo gutput `opod`s gd tbo iurrodt jdput gdly. Kd oqujvklodtstktoaodt usjdm tbo japulso rospgdso bUdQ js tbkt6
Pbogroa 0. Kd LPJ systoa js aoagryloss jc kd` gdly jc
bUdQ 1kUdQ,cgr sgaok I. (8.?)
^rggc. JcbUdQ 1kUdQ, tbod cgr kdy jdput xUdQ, tbo gutput js
yUdQ 1xUdQ bUdQ 1
e1xUeQbUd eQ
1
e1xUeQkUd eQ
1kxUdQ.
Yg, tbo systoa js aoagryloss. Igdvorsoly, jc tbo systoa js aoagryloss, tbod yUdQikddgt `opod` gd tbo vkluosxUeQ cgre1d. Lggejdm kt tbo igdvglutjgd sua cgraulk
yUdQ 1
e1xUeQbUd eQ,
wo igdilu`o tbktbUd eQ 1 >, cgr klle1d,
gr oqujvklodtly,bUdQ 1 >, , cgr klld 1 >.
Pbjs japljosyUdQ 1xUdQbU>Q 1kxUdQ,
wboro wo bkvo sot k 1 bU>Q.
8.9.8 JdvortjhloPbogroa ?. Kd LPJ systoa js jdvortjhlo jc kd` gdly jc tboro oxjstmUdQ suib tbkt
bUdQ mUdQ 1UdQ. (8.3)
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8.9. YZYPOA ^XG^OXPJOY KD@ JA^_LYO XOY^GDYO 9:
^rggc. Jc k systoa Y js jdvortjhlo, tbod x;UdQ1x8UdQ japljos y;UdQ1y8UdQ. Yg tboro
oxjsts kd jdfoitjvo akppjdm (gdo-tg-gdo akp)Ysuib tbktyUdQ 1Y(xUdQ) 1bUdQxUdQ.Yjdioc js jdfoitjvo, tboro oxjsts kd jdvorso akppjdm Y; suib tbktY;(Y(xUdQ)) 1xUdQ,
cgr kdyxUdQ. Pborocgro, tboro oxjsts m UdQ suib tbkt
mUdQ (bUdQ xUdQ) 1xUdQ.Hy kssgijktjvjty gc igdvglutjgd, wo bkvo (mUdQbUdQ)xUdQ 1xUdQ, japlyjdmmUdQbUdQ 1UdQ.
Igdvorsoly, jc tboro oxjst m UdQ suib tbkt bUdQ mUdQ 1UdQ, tbod cgr kdyx;UdQ 1x8UdQ,wo bkvo
y;UdQ 1bUdQ x;UdQy8UdQ 1bUdQ x8UdQ,
kd` y;UdQ 1y8UdQ. Pkejdm tbo `jorodio hotwood y;UdQ kd` y8UdQ, wo bkvoy;UdQ y8UdQ 1bUdQ {x;UdQ x8UdQ} .
Igdvglvjdm hgtb sj`os hy m UdQ yjol`s
mUdQ (y;UdQ y8UdQ) 1UdQ (x;UdQ x8UdQ).Yjdio x;UdQ1 x8UdQ, kd` mUdQ1 > cgr kll d, wo aust bkvo y;UdQ1 y8UdQ. Pborocgro,tbo systoa js jdvortjhlo.
8.9.9 Ikuskl
Pbogroa 3. Kd LPJ systoa js ikuskl jc kd` gdly jc
bUdQ 1 >, cgr klld . (8.=)
^rggc. JcY js ikuskl, tbod tbo gutput yUdQ ikddgt `opod` gd xUeQ cgr e 4 d. Crgatbo igdvglutjgd oquktjgd,
yUdQ 1
e1xUeQbUd eQ,
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0> IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
wo aust bkvo
bUd eQ 1 >, cgre 4 d, gr oqujvklodtly bUd eQ 1 >, cgrd e .Yottjdma 1 d e, wo soo tbkt
bUaQ 1 >, cgr a .
Igdvorsoly, jcbUeQ 1 > cgr e , tbod cgr jdput xUdQ,
yUdQ 1
e1bUeQxUd eQ 1
e1>
bUeQxUd eQ.
Pborocgro,y UdQ `opod`s gdly upgd xUaQ cgr a
d.
8.9.0 Ytkhlo
Pbogroa =. Kd LPJ systoa js stkhlo jc kd` gdly jc
e1
|bUeQ| < .
^rggc. Yuppgso tbkt
e1 |bUeQ| ,;, bUdQ< >.
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8.0. IGDPJD_G_Y-PJAO IGDSGL_PJGD 0;
Ilokrly,|xUdQ| ; cgr kll d. Pbo gutput yU>Q js mjvod hy
|yU>Q| 1 e1
xUeQbUeQ1
e1|bUeQ|
1
e1
|bUeQ| 1 .
Pborocgro,y UdQ js dgt hgud`o`.
8.0 Igdtjdugus-tjao Igdvglutjgd
Pbus ckr wo bkvo hood cgiusjdm gd tbo `jsiroto-tjao ikso. Pbo igdtjdugus-tjao ikso,jd ckit, js kdklgmgus tg tbo `jsiroto-tjao ikso. Jd igdtjdugus-tjao sjmdkls, tbo sjmdkl`oigapgsjtjgd js
x(t) 1
x()(t )`, (8.2)
kd` igdsoquodtly, tbo igdtjdugus tjao igdvglutjgd js `odo` ks
y(t) 1
x()b(t
)`. (8.:)
Oxkaplo.Pbo igdtjdugus-tjao igdvglutjgd klsg cgllgws tbo tbroo stop rulo6 jp, sbjct, aultjply-k` . Pg soo kd oxkaplo, lot us igdsj`or tbo sjmdkl x(t) 1 oktu(t) cgr k 4 >, kd`japulso rospgdso b(t) 1u(t). Pbo gutput y(t) jsIkso K6 t 4>6
y(t) 1
x()b(t )`
1
oku()u(t )
1 t>
ok`
1 ;
k
; okt .
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08 IBK^POX 8. C_D@KAODPKLY GC YZYPOAY
Ikso H6t >6
y(t) 1 >.
Pborocgro,
y(t) 1;
k
; okt u(t).
8.0.; ^rgportjos gc IP Igdvglutjgd
Pbo cgllgwjdm prgportjos ikd ho prgvo` oksjly6
;. Igaautktjvo6 x(t) b(t) 1b(t) x(t)
8. Kssgijktjvo6 x(t) (b;(t) b8(t)) 1 (x(t) b;(t)) b8(t)9. @jstrjhutjvo6 x(t) Ub;(t) +b8(t)Q 1 Ux(t) b;(t)Q + Ux(t) b8(t)Q
8.0.8 Igdtjdugus-tjao Yystoa ^rgportjos
Pbo cgllgwjdm rosults kro kdklgmgus tg tbo `jsiroto-tjao ikso.
Aoagryloss.Kd LPJ systoa js aoagryloss jc kd` gdly jc
b(t) 1k(t), cgr sgao kI.
Jdvortjhlo.Kd LPJ systoa js jdvortjhlo jc kd` gdly jc tboro oxjst m(t) suib tbkt
b(t) m(t) 1(t).Ikuskl.K systoa js ikuskl jc kd` gdly jc
b(t) 1 >, cgr kllt .
Ytkhlo.
K systoa js stkhlo jc kd` gdly jc
|b()|` < .
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Ibkptor 9
Cgurjor Yorjos
Pbo ghfoitjvo gc tbjs ibkptor js tg j`odtjcy k ckajly gc sjmdkls{xe(t)}suib tbkt6;. Ovory sjmdkl jd tbo ckajly pkssos tbrgumb kdy LPJ systoa wjtb gdly k siklo
ibkdmo (gr gtbor sjaply `osirjho` ibkdmo)
xe(t) exe(t),wboroe js k siklo ckitgr.
8. Kdy sjmdkl ikd ho roprosodto` ks k ljdokr igahjdktjgd gc sjmdkls jd tbojrckajly.
x(t) 1
e1 k
exe(t).
Pbjs wgul` kllgw us tg `otorajdo tbo gutput modorkto` hy x(t)6
x(t)
e1keexe(t),
wboro tbo siklkr ke igaos crga tbo `odjtjgd gc ljdokr igahjdktjgd.
9.; Ojmodcuditjgds gc kd LPJ Yystoa
Pg kdswor tbo rst quostjgd, wo doo` tbo dgtjgd gc ojmodcuditjgd gc kd LPJ systoa.
@odjtjgd 8>. Cgr kd LPJ systoa, jc tbo gutput js k siklo` vorsjgd gc jts jdput, tbodtbo jdput cuditjgd js ikllo` kd ojmodcuditjgd gc tbo systoa. Pbo sikljdm ckitgr js ikllo`tbo ojmodvkluo gc tbo systoa.
09
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00 IBK^POX 9. CG_XJOX YOXJOY
9.;.; Igdtjdugus-tjao Ikso
Igdsj`or kd LPJ systoa wjtb japulso rospgdso b(t) kd` jdput sjmdkl x(t)6
Yuppgso tbkt x(t) 1ost cgr sgao s I, tbod tbo gutput js mjvod hy
y(t) 1b(t) x(t) 1
b()x(t )`
1
b()os(t)`
1
b()os`
ost 1B(s)ost 1B(s)x(t),
wboroB(s) js `odo` ks
B(s) 1
b()os`.
Pbo cuditjgdB(s) js edgwd ks tbo trkdscor cuditjgdgc tbo igdtjdugus-tjao LPJ sys-toa. Dgto tbktB(s) js `odo` hy tbo japulso rospgdso b(t), kd` js k cuditjgd jd s(jd`opod`odt gct). Pborocgro, B(s)x(t) ikd ho romkr`o` ks k siklkr B(s) aultjpljo`tg tbo cuditjgd x(t).
Crga tbo `orjvktjgd khgvo, wo soo tbkt jc tbo jdput js x(t) 1ost, tbod tbo gutput jsk siklo` vorsjgd y(t) 1B(s)ost6
Pborocgro, usjdm tbo `odjtjgd gc ojmodcuditjgd, wo sbgw tbkt
;. ost js kd ojmodcuditjgd gc kdy igdtjdugus-tjao LPJ systoa, kd`
8. B(s) js tbo igrrospgd`jdm ojmodvkluo.
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9.;. OJMODC_DIPJGDY GC KD LPJ YZYPOA 0?
Jc wo spoijkljzo tg tbo suhilkss gc porjg`ji igaplox oxpgdodtjkls gc tbo oft , X
hy sottjdm s 1 f, tbod
B(s)|s1f 1B(f) 1
b()of`.
B(f) js ikllo` tbo croquodiy rospgdsogc tbo systoa.
9.;.8 @jsiroto-tjao Ikso
Doxt, wo igdsj`or tbo `jsiroto-tjao ikso6
Yuppgso tbkt tbo japulso rospgdso js mjvod hy bUdQ kd` tbo jdput js xUdQ 1zd, tbodtbo gutput yUdQ js
yUdQ 1bUdQ xUdQ 1
e1bUeQxUd eQ
1
e1bUeQz
d
e
1zd
e1bUeQze 1B(z)zd,
wboro wo `odo`
B(z) 1
e1bUeQze,
kd` B(z) js edgwd ks tbo trkdscor cuditjgd gc tbo `jsiroto-tjao LPJ systoa.
Yjajlkr tg tbo igdtjdugus-tjao ikso, tbjs rosult jd`jiktos tbkt
;. zd js kd ojmodcuditjgd gc k `jsiroto-tjao LPJ systoa, kd`
8. B(z) js tbo igrrospgd`jdm ojmodvkluo.
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03 IBK^POX 9. CG_XJOX YOXJOY
Igdsj`orjdm tbo suhilkss gc porjg`ji igaplox oxpgdodtjkls of(8/D)d hy sottjdm z1of8/D, wo bkvo
B(z)|z1of 1B(of) 1
e1bUeQofe,
wboro 1 8D
, kd` B(of) js ikllo` tbo croquodiy rospgdsogc tbo systoa.
9.;.9 Yuaakry
Jd suaakry, wo bkvo tbo cgllgwjdm ghsorvktjgds6
Pbkt js, ost js kd ojmodcuditjgd gc k IP systoa, wboroks zd js kd ojmodcuditjgd gc k@P systoa. Pbo igrrospgd jdm ojmodvkluos kro B(s) kd`B(z).
Jc wo suhstjtutos 1 fkd`z1 of rospoitjvoly, tbod tbo ojmodcuditjgds hoigaooft
kd` ofd5 tbo ojmodvkluos hoigao B(f) kd` B(of).
9.;.0 ]by js ojmodcuditjgd japgrtkdt7
Pbo kdswor tg tbjs quostjgd js rolkto` tg tbo soigd` ghfoitjvo jd tbo homjddjdm. Lotus igdsj`or k sjmdklx(t)6
x(t) 1k;os;t +k8o
s8t +k9os9t.
Kiigr`jdm tbo ojmodcuditjgd kdklysjs, tbo gutput gc okib igaplox oxpgdodtjkl jsos;t B(s;)os;tos8t B(s8)os8t
os9t B(s9)os9t.
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9.8. CG_XJOX YOXJOY XO^XOYODPKPJGD 0=
Pborocgro, tbo gutput js
y(t) 1k;B(s;)os;t +k8B(s8)os8t +k9B(s9)os9t.
Pbo rosult japljos tbkt jc tbo jdput js k ljdokr igahjdktjgd gc igaplox oxpgdodtjkls,tbo gutput gc kd LPJ systoa js klsg k ljdokr igahjdktjgd gc igaplox oxpgdodtjkls.Agro modorklly, jcx(t) js kd jddjto sua gc igaplox oxpgdodtjkls,
x(t) 1
e1keo
set,
tbod tbo gutput js kmkjd k sua gc igaplox oxpgdodtjkls6
y(t) 1 e1
keB(se)oset.
Yjajlkrly cgr `jsiroto-tjao sjmdkls, jc
xUdQ 1
e1kez
de ,
tbod
xUdQ 1
e1keB(ze)z
de .
Pbjs js kd japgrtkdt ghsorvktjgd, hoikuso ks lgdm ks wo ikd oxpross k sjmdkl x(t) ksk ljdokr igahjdktjgd gc ojmodcuditjgds, tbod tbo gutput y(t) ikd ho oksjly `otorajdo`hy lggejdm kt tbo trkdscor cuditjgd (wbjib js xo` cgr kd LPJ systoa!). Dgw, tboquostjgd js 6 Bgw `g wo oxpross k sjmdkl x(t) ks k ljdokr igahjdktjgd gc igaploxoxpgdodtjkls7
9.8 Cgurjor Yorjos Xoprosodtktjgd
Oxjstodio gc Cgurjor Yorjos
Jd modorkl, dgt ovory sjmdklx(t) ikd ho `oigapgso` ks k ljdokr igahjdktjgd gc igaploxoxpgdodtjkls. Bgwovor, suib `oigapgsjtjgd js stjll pgssjhlo cgr kd oxtroaoly lkrmo ilkssgc sjmdkls. ]o wkdt tg stu`y gdo ilkss gc sjmdkls tbkt kllgws tbo `oigapgsjtjgd. Pboykro tbo porjg`ji sjmdkls
x(t+P) 1x(t)
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02 IBK^POX 9. CG_XJOX YOXJOY
wbjib sktjscy tbo squkro jdtomrkhlo igd`jtjgd,
P
|x(t)|8`t < ,
gr @jrjiblot igd`jtjgds (Zgu aky d` agro `jsiussjgds jd G]9.0)6;. Gvor kdy porjg` x(t) aust ho khsglutoly jdtomrkhlo, tbkt js,
P
|x(t)|`t < .
8. Jd kdy djto jdtorvkl gc tjao x(t) js gc hgud`o` vkrjktjgd5 tbkt js, tboro kro dgagro tbkd k djto duahor gc akxjak kd` ajdjak `urjdm kdy sjdmlo porjg` gctbo sjmdkl.
9. Jd kdy djto jdtorvkl gc tjao, tboro kro gdly k djto duahor gc `jsigdtjdujtjos.
Cgr tbjs ilkss gc sjmdkls, wo kro khlo tg oxpross jt ks k ljdokr igahjdktjgd gc igaploxoxpgdodtjkls6
x(t) 1
e1keo
fe>t.
Boro,> js tbo cud`kaodtkl croquodiy
>18
P ,
kd` tbo igoijodts ke kro edgwd ks tbo Cgurjor Yorjos igoijodts.
Mjvod k porjg`ji sjmdklx(t) tbkt js squkro jdtomrkhlo, bgw `g wo `otorajdo tbo CgurjorYorjos igoijodtske7 Pbjs js kdsworo` hy tbo cgllgwjdm tbogroa.
9.8.; Igdtjdugus-tjao Cgurjor Yorjos Igoijodts
Pbogroa 2. Pbo igdtjdugus-tjao Cgurjor sorjos igoijodtske gc tbo sjmdkl
x(t) 1
e1 keofe>t,
js mjvod hy
ke 1 ;
P
P
x(t)ofe>t`t.
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9.8. CG_XJOX YOXJOY XO^XOYODPKPJGD 0:
^rggc. Lot us igdsj`or tbo sjmdkl
x(t) 1
e1keo
fe>t.
Jc wo aultjply gd hgtb sj`os ofd>t, tbod wo bkvo
x(t)ofd>t 1
e1
keofe>t
ofd>t 1
e1
keof(ed)>t.
Jdtomrktjdm hgtb sj`os crga > tg P yjol`s
P
> x(t)ofd>t
`t1 P
>
e1 keof(ed)>t `t1
e1
ke
P>
of(ed)>t`t
.
Pbo toraP> o
f(ed)>t`tikd ho ovklukto` ks (Zgu sbgul` iboie tbjs!)
;
P
P>
of(ed)>t`t1
; jce1 d> gtborwjso
(9.;)
Pbjs rosult js edgwd ks tbo grtbgmgdkljtygc tbo igaplox oxpgdodtjkls.
_sjdm Oq. (9.;), wo bkvo P>
x(t)ofd>t`t1 P kd,
wbjib js oqujvklodt tg
kd1 ;
P
P>
x(t)ofd>t`t.
Oxkaplo ;. Yjdusgj`sIgdsj`or tbo sjmdklx(t) 1 ;+ ;
8igs 8t+sjd9t. Pbo porjg` gcx(t) jsP1 8 U]by7Q sg
tbo cud`kaodtkl croquodiy js> 1 8P 1. Xoikll Oulors cgraulkof 1 igs +fsjd ,
wo bkvo
x(t) 1 ; +;
0
of8t +of8t
+
;
8f
of9t of9t .
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9.8. CG_XJOX YOXJOY XO^XOYODPKPJGD ?;
9.8.8 @jsiroto-tjao Cgurjor Yorjos igoijodts
Pg igdstruit tbo `jsiroto-tjao Cgurjor sorjos roprosodtktjgd, wo igdsj`or porjg`ji`jsiroto-tjao sjmdkl wjtb porjg`D
xUdQ 1xUd+DQ,
kd` kssuao tbkt xUdQ js squkro-suaakhlo, j.o.,
d1 |xUdQ|8 d,
js mjvod hy
ke 1 ;
D
d1DxUdQofe>d.
Boro,
d1Daokds suaajdm tbo sjmdkl wjtbjd k porjg`D. Yjdio k porjg`ji `jsiroto-tjao sjmdkls ropokts ovory Dskaplos, jt `gos dgt akttor wbjib skaplo tg ho pjieo`rst.
Oxkaplo.Lot us igdsj`or tbo cgllgwjdm sjmdkl sbgwd holgw. ]o wkdt tg `otorajdo tbo `jsiroto-tjao C.Y. igoijodt.
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9.8. CG_XJOX YOXJOY XO^XOYODPKPJGD ?9
Pbod, tbo gutput sjmdkl js mjvod hy
y(t) 1
e1keB(fe>)o
fe>t.
Lottjdmhe 1B(fe>)ke, wo bkvo
y(t) 1
e1heo
fe>t.
9.8.0 Bgw akdy Cgurjor sorjos igoijodts kro suijodt7
Jc wo `odo
xD(t) 1D
e1Dkeo
fe>t,
tbod xD(t) js kd kpprgxjaktjgd gcx(t). Ks D , wo soo tbkt xD(t) x(t). Kskd jllustrktjgd gcxD(t) ks Djdiroksos, wo ikd soo tbo cgllgwjdm muro.
Pborocgro, tbo duahor gc Cgurjor sorjos igoijodts `opod`s gd tbo kiiurkiy tbkt wowkdt tg kibjovo. Pypjiklly, tbo duahor D js ibgsod suib tbkt tbo rosj`uo gc tbo
kpprgxjaktjgd
|x(t) xD(t)|8 `t ,
cgr sgao tkrmot orrgr lovol.
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9.9. ^XG^OXPJOY GC CG_XJOX YOXJOY IGOCCJIJODPY ??
Lottjdm1t t> jd tbo jdtomrkl, wo ghtkjd
;P
P
x()ofe>(+t>)`1ofe>t> ;P
P
x()ofe>`
wborox(t) ke. Pborocgro,x(t t>) keofe>t> .
9. Pjao Xovorskl6
x(t) kexUdQ ke
Pbo prggc js sjaplo. Igdsj`or k sjmdkly(t) 1 x(t). Pbo C.Y. roprosodtktjgdgcx(
t) js
x(t) 1
e1keo
fe8t/P.
Lottjdme 1 a, wo bkvo
y(t) 1x(t) 1
a1kaofa8t/P.
Pbus, x(t) ke.0. Igdfumktjgd6
x(t) kexUdQ ke
?. Aultjpljiktjgd6 Jcx(t) ke kd` y(t) he, tbod
x(t)y(t)
l1kehel.
3. ^krsovkl Oqukljty6
;
P P|x(t)|8`t1
e1|ke|8
;
D
d1D
|xUdQ|8 1
e1D|ke|8
Zgu kro roqujro` tg rok` Pkhlo 9.; kd` 9.8.
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?3 IBK^POX 9. CG_XJOX YOXJOY
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Ibkptor 0
Igdtjdugus-tjao Cgurjor Prkdscgra
Lot us homjd gur `jsiussjgd hy rovjowjdm sgao ljajtktjgds gc Cgurjor sorjos roprosod-tktjgd. Jd Cgurjor sorjos kdklysjs, twg igd`jtjgds gd tbo sjmdkls kro roqujro`6
;. Pbo sjmdkl aust ho porjg`ji, j.o., tboro oxjst k P 4> suib tbkt x(t + P) 1x(t).
8. Pbo sjmdkl aust ho squkro jdtomrkhloP
|x(t)|8`t < , gr sktjsos tbo @jrjiblotigd`jtjgds.
Jd tbjs ibkptor, wo wkdt tg oxtod` tbo j`ok gc Cgurjor Yorjos roprosodtktjgd tg kporj-g`ji sjmdkls. Pbkt js, wo wkdt tg rolkx tbo rst igd`jtjgd tg kporjg`ji sjmdkls.
0.; Jdsjmbt crga Cgurjor Yorjos
Lots rst igdsj`or tbo cgllgwjdm porjg`ji sjmdkl
x(t) 1
; |t| P;,> P; |t| < P8 ,
wborox(t) 1x(t+P). Pbo Cgurjor Yorjos igoijodts gcx(t) kro (iboie ygursolc!)
x(t) C.Y.
ke 1
8sjd(e>P;)
e>P
.
Jc wo suhstjtuto 1 e>, tbod
ke 18sjd(P;)
wP
1e>
?=
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?2 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
AultjplyjdmPgd hgtb sj`os yjol`s
P ke 18sjd(P;)
, (0.;)
wbjib js tbo dgrakljzo` Cgurjor Yorjos igoijodt.
^jitgrjklly, (0.;) jd`jiktos tbkt tbo dgrakljzo` Cgurjor sorjos igoijodts P ke kro
hgud`o` hy tbo odvolgp R() 1 8 sjd(P;)
, ks jllustrkto` jd Cjm. 0.;.
Cjmuro 0.;6 Cgurjor Yorjos igoijodts gcx(t) cgr sgao P.
]bodP jdiroksos, tbo spkijdm hotwood igdsoiutjvo ke ro`uios. Bgwovor, tbo sbkpogc tbo odvolgp cuditjgd R() 1 8 sjd(P;)
roakjds tbo skao. Pbjs ikd ho sood jd Cjm.
0.8.
Cjmuro 0.86 Cgurjor Yorjos igoijodts gcx(t) cgr sgao P, wboro P 4 P.
Jd tbo ljajtjdm ikso wboroP , tbod tbo Cgurjor sorjos igoijodtsP ke kpprgkibostbo odvolgp cuditjgd R(). Pbjs summosts us tbkt jc wo bkvo kd kporjg`ji sjmdkl, woikd trokt jt ks k porjg`ji sjmdkl wjtb P . Pbod tbo igrrospgd`jdm Cgurjor sorjosigoijodts kpprgkib tg tbo odvolgp cuditjgd R(). Pbo odvolgp cuditjgd js ikllo`tbo Cgurjor Prkdscgra gc tbo sjmdkl x(t). Dgw, lot us stu`y Cgurjor Prkdscgra agrocgraklly.
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0.8. CG_XJOX PXKDYCGXA ?:
0.8 Cgurjor Prkdscgra
Pbo `orjvktjgd gc Cgurjor Prkdscgra igdsjsts gc tbroo stops.
Ytop ;.
]o kssuao tbkt kd kporjg`ji sjmdklx(t) bks djto `urktjgd, j.o.,x(t) 1 > cgr |t| 4 P /8,cgr sgao P. Yjdio x(t) js kporjg`ji, wo rst igdstruit k porjg`ji sjmdklx(t)6
x(t) 1x(t),cgrP /8< t < P/8, kd`
x(t+P) 1
x(t). ^jitgrjklly, wo bkvo
Ytop 8.
Yjdiox(t) js porjg`ji, wo aky oxprossx(t) usjdm Cgurjor Yorjos6
x(t) 1
e1keo
fe>t (0.8)
wboro
ke 1 ;
P
P
x(t)ofe>t`t.Pbo Cgurjor Yorjos igoijodts ke ikd curtbor ho ikliulkto` ks
ke 1 ;
P
P8
P8
x(t)ofe>t`t1
;
P
P8
P8
x(t)ofe>t`t,
x(t) 1x(t), cgr P /8< t < P/8
1 ;P x(t)ofe>t`t, x(t) 1 >, cgr|t| 4 P /8.Jc wo `odo
R(f) 1
x(t)oft`t (0.9)
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38 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
Cjmuro 0.06 Cgurjor Prkdscgra gd kporjg`ji sjmdkls js oqujvklodt tg kpplyjdm Cgurjorsorjos kdklysjs gd tbo porjg`jiklly pk``o` vorsjgd gc tbo sjmdkl, kd` sot tbo ljajt gc> >.
gcx(t) js P>, tbod > 1 8P>
. Dgw, sjdiox(t) js porjg`ji, wo ikd kpply CgurjorYorjos kdklysjs tgx(t) kd` mot
x(t) 1
e1 keofe>t, (0.:)
wboroke js tbo Cgurjor Yorjos igoijodt. Jc wo curtbor kpply Cgurjor Prkdscgratg (0.:), tbod wo bkvo
R(f) 1
e1
keofe>t
oft`t
1
e1ke
ofe>toft`t
1
e1ke8( e>).
Boro, tbo lkst oqukljty js ostkhljsbo` hy tbo ckit tbkt jdvorso Cgurjor Prkdscgra
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0.9. XOLKPJGD PG CG_XJOX YOXJOY 39
gc 8( e>) jsofe>t. Pg sbgw tbjs, wo bkvo
C;{8( e>)} 1 ;8
8( e>)ofwt`w
1
( e>)ofe>t`w1 ofe>t.
Pborocgro, wo sbgwo` tbkt tbo Cgurjor Prkdscgra gc k porjg`ji sjmdkl js k trkjdgc japulsos wjtb kapljtu`o `odo` hy tbo Cgurjor Yorjos igoijodts (kd` siklo`hy k ckitgr gc 8).
Cjmuro 0.?6 Cgurjor Prkdscgra kd` Cgurjor Yorjos kdklysjs gc k porjg`ji sjmdkl6 Hgtbyjol s k trkjd gc japulsos. Cgr Cgurjor Prkdscgra, tbo kapljtu`o js aultjpljo` hy kckitgr gc 8. Cgr Cgurjor Yorjos igoijodts, tbo sopkrktjgd hotwood okib igoijodt js>.
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30 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
0.0 Oxkaplos
Oxkaplo ;.Igdsj`or tbo sjmdkl x(t) 1 oktu(t), cgr k 4 >. @otorajdo tbo Cgurjor PrkdscgraR(f), jts akmdjtu`o|R(f)| kd` jts pbkso R(f).
R(f) 1
x(t)oftu(t)`t
1
>
oktoft`t , u(t) 1 >, wbodovor t
1 ;k +f
o(k+f)t
>
1 ;k +f
.
Pbo akmdjtu`o kd` pbkso ikd ho ikliulkto` ks
|R(f)| 1 ;k8 +8
R(f) 1 tkd;
k
.
Oxkaplo 8.Igdsj or tbo sjmdklx(t) 1(t). Pbo Cgurjor Prkdscgra js
R(f) 1
x(t)oft`t
1
(t)oft`t1 ;.
Oxkaplo 9.Igdsj`or tbo sjmdkl x(t) 1 of>t. ]o wkdt tg sbgw tbkt R(f) 1 8( >). Pg
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0.0. ORKA^LOY 3?
soo, wo tkeo tbo jdvorso Cgurjor Prkdscgra6
x(t) 1 ;8
R(f)oft`
1
( >)oft`
1of>t
( >)`1 of>t.
Oxkaplo 0.Igdsj`or tbo kporjg`ji sjmdkl
x(t) 1 ; |t| P;> |t| 4 P;
Pbo Cgurjor Prkdscgra js
R(f) 1
x(t)oft`t
1
P;P;
oft`t1;f
oft
P;P; 1 8
sjd P;
.
Oxkaplo ?.Lot us `otorajdo tbo IPCP gc tbo udjt stop cuditjgdu(t). Pg `g sg, wo kpply IPCPkd` mot
_(f) 1
u(t)oft`t1 >
oft`t1 ;f
oft>
.
Pbkt js, wo bkvo tg ovklukto tbo cuditjgd ;f oft kt t 1 > kd` t 1. Bgwovor,
tbo ovkluktjgd kt t 1 js jd`otorajdkto! Pborocgro, wo oxpross y(t) ks k ljajt gc`oikyjdm oxpgdodtjkls
u(t) 1 ljak>
oktu(t).
Pbod kpplyjdm IPCP gd hgtb sj`os,
_(f) 1 ljak
>Co
ktu(t)1 ljak>;
k +f
1 ljak>
k fk8 +8
1 ljak>
k
k8 +8f
k8 +8
.
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33 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
Dgw, tbo soigd` tora js
ljak>f
k8 +8 1 ;
f .
Pbo rst tora sktjsos
ljak>
k
k8 +8 1 >, cgr 1 >.
kd`
ljak>
k
k8 +81 lja
k>;
k1 , cgr 1 >,
wbjlo
k
k8 +8`1 tkd;
k
1,
k
X.
Pborocgro,
ljak>
k
k8 +8 1(),
kd` sg
_(f) 1 ;
f+().
0.? ^rgportjos gc Cgurjor Prkdscgra
Pbo prgportjos gc Cgurjor Prkdscgra js vory sjajlkr tg tbgso gc Cgurjor Yorjos.
;. Ljdokrjty Jcx;(t) R;(f) kd`x8(t) R8(f), tbod
kx;(t) +hx8(t) kR;(f) +hR8(f).
8. Pjao Ybjctjdm
x(t t>) oft>R(f)
^bysjikl jdtorprotktjgd gcoft> 6
oft>R(f) 1 |R(f)|ofR(f)oft>1 |R(f)|ofUR(f)t>Q
Ygoft> js igdtrjhutjdm tg pbkso sbjct gcR(f).
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0.?. ^XG^OXPJOY GC CG_XJOX PXKDYCGXA 3=
9. Igdfumktjgd
x(t) R(f)Jcx(t) js rokl, tbod x(t) 1x(t), sg R(f) 1R(f).
0. @jorodtjktjgd kd` Jdtomrktjgd
`
`tx(t) fR(f) t
x()` ;
fR(f) +R(>)()
?. Pjao Yikljdm
x(t) ;|k|R(f
k )
3. ^krsovkl Oqukljty
|x(t)|8`t1 ;8
|R(f)|8`
=. @ukljty Pbo japgrtkdt aosskmo boro js6 Jcx(t) R(f), tbod jc kdgtbor sjmdkly(t) bks tbo sbkpo gcR(f), wo ikd qujiely `o`uio tbkt R(f) wjll bkvo tbosbkpo gcx(t). Boro kro twg oxkaplos6
@ukljty Oxkaplo ; @ukljty Oxkaplo 8
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32 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
2. Igdvglutjgd ^rgporty
b(t) x(t) B(f)R(f)^rggc6 Igdsj`or tbo igdvglutjgd jdtomrkl
y(t) 1
x()b(t )`
Pkejdm Cgurjor Prkdscgra gd hgtb sj`os yjol`s
Z(f) 1 C
x()b(t )`
1
x()b(t )` oft`t1
x()
b(t )oft`t
`
1
x()
ofB(f)
`
1
x()of` B(f)
1R(f)B(f)
:. Aultjpljiktjgd ^rgporty (ygu ikd `orjvo tbjs hy ygursolc)
x(t)y(t) ;8
R(f) Z(f)
Oxkaplo.Igdsj`or tbo sjmdkl x(t) 1 a(t)igs(>t), wboro a(t) js sgao hkd`ljajto` sjmdkl.Yuppgso tbo Cgurjor Prkdscgra gca(t) jsA(f). Yjdio
igs(>t) 1of>t +of>t
8 U( >) +(+>)Q,
hy igdvglutjgd prgporty, tbo IPCP gcx(t) js
a(t)igs(>t) ;8
A(f) U( >) +(+>)Q
1;
8UA(f( >)) +A(f(+>))Q .
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0.3. YZYPOA KDKLZYJY _YJDM CG_XJOX PXKDYCGXA 3:
0.3 Yystoa Kdklysjs usjdm Cgurjor Prkdscgra
Cjrst Gr`or YystoaLot us igdsj`or tbo rst gr`or systoa
`y(t)
`t +ky(t) 1x(t), (0.;>)
cgr sgao k 4>. Kpplyjdm tbo IPCP tg hgtb sj`os,
C
`y(t)
`t +ky(t)
1 C {x(t)} ,
kd` uso ljdokrjty prgporty, kd` `jorodtjktjgd prgporty gc IPCP, wo bkvo
fZ(f) +kZ(f) 1R(f).
Xokrrkdmjdm tbo toras, wo ikd d` tbo croquodiy rospgdso gc tbo systoa
B(f) 1 Z(f)
R(f)1
;
k +f.
Dgw, roikll tbo IPCP pkjr6
b(t) 1oktu(t) B(f) 1 ;k +f
, (0.;;)
b(t) ikd ho `o`uio`. Fust ks qujie `orjvktjgd gc tbjs oquktjgd, wo dgto tbkt
B(f) 1
oktu(t)oft`t1>
o(f+k)t`t
1
;
f +ko(f+k)t
>
1 ;
f +k.
Modorkl YystoasJd modorkl, wo wkdt tg stu`y tbo systoa
D
e1>ke
`ey(t)
`te 1
A
e1>he
`ex(t)
`te . (0.;8)
Gur ghfoitjvo js tg `otorajdo b(t) kd`B(f). Kpplyjdm IPCP gd hgtb sj`os6
C
De1>
ke`ey(t)
`te
1 C
Ae1>
he`ex(t)
`te
.
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=> IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
Pborocgro, hy ljdokrjty kd` `jorodtjktjgd prgporty, wo bkvo
De1>
ke(f)eZ(f) 1
Ae1>
he(f)eR(f).
Pbo igdvglutjgd prgporty mjvos Z(f) 1R(f)B(f), sg
B(f) 1 Z(f)
R(f)1
Ae1> he(f)
eDe1> ke(f)
e. (0.;9)
Dgw,B(f) js oxprosso` ks k rktjgdkl cuditjgd, j.o., k rktjg gc pglydgajkl. Pborocgro,wo ikd kpply tbo toibdjquo gc pkrtjkl crkitjgd oxpkdsjgd tg oxpross B(f) jd k cgra
tbkt kllgws us tg `otorajdo b(t) hy jdspoitjgd usjdm tbo trkdscgra pkjr
b(t) 1oktu(t) B(f) 1 ;k +f
,
kd` rolkto` trkdscgra pkjr, suib ks
toktu(t) ;(k +f)8
.
Oxkaplo ;.Igdsj`or tbo LPJ systoa
`8y(t)
`t8 + 0y(t) + 9y(t) 1
`x(t)
`t + 8x(t).
Pkejdm IPCP gd hgtb sj`os yjol`s
(f)8Z(f) + 0fZ(f) + 9Z(f) 1fR(f) + 8R(f).
kd` hy rokrrkdmjdm toras wo bkvo
B(f) 1 f + 8
(f)8 + 0(f) + 91
f + 8
(f + ;)(f + 9).
Pbod, hy pkrtjkl crkitjgd oxpkdsjgd wo bkvo
B(f) 1;
8
;
f + ;
+
;
8
;
f + 9
.
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0.3. YZYPOA KDKLZYJY _YJDM CG_XJOX PXKDYCGXA =;
Pbus, b(t) js
b(t) 1;
8ot
u(t) +;
8o9t
u(t).
Oxkaplo 8.Jc tbo jdput sjmdkl js x(t) 1 otu(t), wbkt sbgul` ho tbo gutput y(t) jc tbo japulsorospgdso gc tbo systoa js mjvod hy b(t) 1 ;
8otu(t) + ;
8o9tu(t)7
Pkejdm IPCP, wo edgw tbkt R(f) 1 ;f+;
, kd` B(f) 1 f+8(f+;)(f+9)
. Pborocgro,tbo gutput js
Z(f) 1B(f)R(f) 1
f + 8
(f + ;)(f + 9)
;
f + ;
1
f + 8
(f + ;)8(f + 9).
Hy pkrtjkl crkitjgd oxpkdsjgd, wo bkvo
Z(f) 1;0
f + ;+
;8
(f + ;)8
;0
f + 9.
Pborocgro, tbo gutput js
y(t) 1
;
0ot +
;
8tot ;
0o9t
u(t).
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=8 IBK^POX 0. IGDPJD_G_Y-PJAO CG_XJOX PXKDYCGXA
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Ibkptor ?
@jsiroto-tjao Cgurjor Prkdscgra
?.; Xovjow gd Igdtjdugus-tjao Cgurjor Prkdscgra
Hocgro wo `orjvo tbo `jsiroto-tjao Cgurjor Prkdscgra, lot us roikll tbo wky wo igd-struito` igdtjdugus-tjao Cgurjor Prkdscgra crga tbo igdtjdugus-tjao Cgurjor Yorjos.Jd `orjvjdm tbo igdtjdugus-tjao Cgurjor Prkdscgra, wo hksjiklly bkvo tbo cgllgwjdmtbroo stops6
Ytop ;6 ^k` tbo kporjg`ji sjmdkl ; x(t) tg igdstruit k porjg`ji ropljikto x(t)
Ytop 86 Yjdio x (t) js porjg`ji, wo d` tbo Cgurjor sorjos igoijodts ke kd`roprosodt x(t) ks
x (t) 1 e1
keofe>t.
;]o kro jdtorosto` jd kporjg`ji sjmdkls, hoikuso porjg`ji sjmdkls ikd ho bkd`lo` usjdm igdtjdugus-tjao Cgurjor Yorjos!
=9
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=0 IBK^POX ?. @JYIXOPO-PJAO CG_XJOX PXKDYCGXA
Hy `odjdm
R(f) 1
x (t) oft`t, (?.;)
wbjib js edgwd ks tbo igdtjdugus-tjao Cgurjor Prkdscgra, wo sbgwo`
ke 1 ;
PR(fe>) .
Ytop 96 Yottjdm P , wo sbgwo` x (t) x (t) kd`
x (t) 1
;
8
R(f) oft
`t (?.8)
?.8 @orjvjdm @jsiroto-tjao Cgurjor Prkdscgra
Dgw, lots kpply tbo skao igdiopt tg `jsiroto-tjao sjmdkls. Jd `orjvjdm tbo `jsiroto-tjao Cgurjor Prkdscgra, wo klsg bkvo tbroo eoy stops.
Ytop ;6 Igdsj`or kd kporjg`ji `jsiroto-tjao sjmdkl xUdQ. ]o pk`xUdQ tg igd-struit k porjg`ji sjmdkl xUdQ.
Ytop 86 Yjdio xUdQ js porjg`ji, hy `jsiroto-tjao Cgurjor Yorjos wo bkvo
xUdQ 1
e1Dkeo
fe>d, (?.9)
wboroke ikd ho igaputo` ks
ke 1 ;
D
d1D
x UdQ ofe>d.
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?.8. @OXJSJDM @JYIXOPO-PJAO CG_XJOX PXKDYCGXA =?
Boro, tbo croquodiy js
>1
8
D.
Dgw, dgto tbkt xUdQ js k porjg`ji sjmdkl wjtb porjg`D, kd` tbo dgd-zorg odtrjosgc xUdQ jd k porjg` kro tbo skao ks tbo dgd-zorg odtrjos gcxUdQ. Pborocgro, jtbgl`s tbkt
ke 1 ;
D
d1D
x UdQ ofe>d
1 ;
D
d1
x UdQ ofe>d.
Jc wo `odo
R(of ) 1
d1xUdQofd, (?.0)
tbod
ke 1 ;
D
d1
xUdQofe>d 1 ;
DR(ofe>). (?.?)
Ytop 96 ^uttjdm Oquktjgd (?.?) jdtg Oquktjgd (?.9), wo bkvoxUdQ 1 e1D keofe>d
1
e1D
;
DR(ofe>)
ofe>d
1 ;
8
e1D
R(ofe>)ofe>d>, >18
D. (?.3)
KsD , > > kd` xUdQ xUdQ. Klsg, crga Oquktjgd (?.3) hoigaos
xUdQ 1 ;
8 e1DR(ofe>)ofe>d> ;
8
8
R(of)ofd`.
Pborocgro,
xUdQ 1 ;
8
8
R(of )ofd`. (?.=)
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=3 IBK^POX ?. @JYIXOPO-PJAO CG_XJOX PXKDYCGXA
Cjmuro ?.;6 KsD , > >. Yg tbo krok hoigaos jddjtosjakl sakll kd` suahoigaos jdtomrktjgd.
?.9 ]by js R(of
) porjg`ji 7Jt js jdtorostjdm tg dgto tbkt tbo igdtjdugus-tjao Cgurjor PrkdscgraR(f) js kporjg`jijd modorkl, hut tbo `jsiroto-tjao Cgurjor PrkdscgraR(of) js klwkys porjg`ji. Pg sootbjs, lot us igdsj`or tbo `jsiroto-tjao Cgurjor Prkdscgra (wo wkdt tg iboie wbotborR(of) 1R(of(+8))!)6
R(of(+8)) 1
d1
xUdQof(+8)d
1
d1 xUdQofd(of8)d 1R(of),hoikuso (of8)d 1 ;d 1 ;, cgr kdy jdtomor d. Pborocgro, R(of ) js porjg`ji wjtbporjg` 8.
Dgw, lot us igdsj`or tbo igdtjdugus-tjao Cgurjor Prkdscgra (wo wkdt tg iboie wbotborR(f) 1R(f(+ 8))!)6
R(f(+ 8)) 1
x(t)of(+8)t`t1
x(t)oft(of8)t`t.
Boro,t Xkd` js ruddjdm crgatg. ^ky kttodtjgd tbkt of8t 1 ; udloss t jskd jdtomor (wbjib `jorodt crga tbo `jsiroto-tjao ikso wboro d js klwkys kd jdtomor!).Pborocgro,
x(t)oftof8t`t 1
x(t)oft`t,
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?.0. ^XG^OXPJOY GC @JYIXOPO-PJAO CG_XJOX PXKDYCGXA ==
(k) (of8)d 1 ; cgr kll d, hoikuso d js jdtomor. (h) (of8)t 1 ; udloss t js kd jdtomor.
kd` igdsoquodtly, R(f(+ 8)) 1R(f).
?.0 ^rgportjos gc @jsiroto-tjao Cgurjor Prkdscgra
@jsiroto-tjao Cgurjor Prkdscgra6
R(of) 1
d1xUdQofd
@jsiroto-tjao Jdvorso Cgurjor Prkdscgra6
xUdQ 1 ;
8
8
R(of )ofd`
;. ^orjg`jijty6R(of(+8)) 1R(of)
8. Ljdokrjty6kx;UdQ +hx8UdQ kR;(of) +hR8(of)
9. Pjao Ybjct6 xUd d>Q ofd>R(of)
0. ^bkso Ybjct6
of>dxUdQ R(of(>))
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=2 IBK^POX ?. @JYIXOPO-PJAO CG_XJOX PXKDYCGXA
?. Igdfumkiy6
xUdQ R(of
)
3. Pjao XovorsklxUdQ R(of )
=. @jorodtjktjgd
dxUdQ f `R(of )
`
2. ^krsovkl Oqukljty
d1 |xUdQ|8 1 ;8 8 |R(of )|8`:. Igdvglutjgd
yUdQ 1xUdQ bUdQ Z(of) 1R(of)B(of )
;>. Aultjpljiktjgd
yUdQ 1x;UdQx8UdQ Z(of) 1 ;8
8
R;(of)R8(o
f())`
?.? Oxkaplos
Oxkaplo ;.Igdsj`orxUdQ 1UdQ +Ud ;Q +Ud+ ;Q. Pbod
R(of ) 1
d1xUdQofd
1
d1(UdQ +Ud ;Q +Ud+ ;Q)ofd
1
d1UdQofd +
d1
Ud ;Qofd +
d1Ud+ ;Qofd
1 ; +of +of 1 ; + 8 igs .
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?.?. ORKA^LOY =:
Cjmuro ?.86 Akmdjtu`o plgt gc|R(of)| jd Oxkaplo ;.
Pg seotib tbo akmdjtu`o|R(of )|, wo dgto tbkt|R(of)| 1 |; + 8 igs |.
Oxkaplo 8.Igdsj`orxUdQ 1UdQ + 8Ud ;Q + 0Ud 8Q. Pbo `jsiroto-tjao Cgurjor Prkdscgra js
R(of ) 1 ; + 8of + 0of0.
Jc tbo japulso rospgdso js bUdQ 1UdQ +Ud ;Q, tbod
B(of) 1 ; +of .
Pborocgro, tbo gutput js
Z(of ) 1B(of)R(of)
1
; +of
; + 8of + 0of8
1 ; + 9of + 3of8 + 0of9.
Pkejdm tbo jdvorso `jsiroto-tjao Cgurjor Prkdscgra, wo bkvo
yUdQ 1UdQ + 9Ud ;Q + 3Ud 8Q + 0Ud 9Q.Oxkaplo 9.Igdsj`orxUdQ 1kduUdQ, wjtb|k|
kdofd 1d1>
(kof)d 1 ;
; kof .
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2> IBK^POX ?. @JYIXOPO-PJAO CG_XJOX PXKDYCGXA
(k) >< k < ; (h);< k < >
Doxt, lot us `rkw tbo akmdjtu`o|R(of)|. Pg `g sg, lots igdsj`or
R(of)8
1R(of)R(of) 1 ;
; kof
;
; kof
1 ;
; k(ofof) +k8
1 ;
; 8k igs +k8Ikso K. Jc >< k , kd`|R(of)|8kibjovos ajdjaua wbod 1 . Pbus,
akxR(of)
8
1 ;
; 8k +k8 1 ;
(; k)8
ajd R(of)81 ;; + 8k +k8 1 ;(; +k)8 .Ikso H6Jc;< k , tbod |R(of)|8 kibjovos akxjaua wbod 1 , kd` |R(of)|8kibjovos ajdjaua wbod 1 >. Pbus,
akxR(of )81 ;
; + 8k +k8 1
;
(; +k)8
ajdR(of )81 ;
; 8k +k8 1 ;
(; k)8 .
?.3 @jsiroto-tjao Cjltors
Jd `jmjtkl sjmdkl prgiossjdm, tboro kro modorklly cgur typos gc ltors tbkt wo gctod uso.Dkaoly, tboy kro tbo lgwpkss ltors, bjmbpkss ltors, hkd`pkss ltors kd` hkd`stgpltors. Pboro js dg proijso `odjtjgd cgr hojdm lgw gr bjmb. Bgwovor, jt js usukllyoksy tg jdcor tbo typo crga vjowjdm tbojr akmdjtu`o rospgdso.
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?.=. K^^OD@JR 2;
(k) Kd j`okl lgwpkss ltor (h) Kd j`okl bjmbpkss ltor
(i) Kd j`okl hkd`pkss ltor (`) Kd j`okl hkd`stgp ltor
?.= Kppod`jx
Mogaotrji Yorjos6
Dd1>
xd 1 ; +x+x8 +. . .+xd 1; xD+;
; x ,
d1>
xd 1 ; +x+x8 +. . .1 ;
; x, wbod|x|
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28 IBK^POX ?. @JYIXOPO-PJAO CG_XJOX PXKDYCGXA
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Ibkptor 3
Ykapljdm Pbogroa
Ykapljdm tbogroa plkys k iruijkl rglo jd ag`ord `jmjtkl sjmdkl prgiossjdm. Pbo tbo-groa igdiords khgut tbo ajdjaua skapljdm rkto roqujro` tg igdvort k igdtjdugustjao sjmdkl tg k `jmjtkl sjmdkl, wjtbgut lgss gc jdcgraktjgd.
3.; Kdklgm tg @jmjtkl Igdvorsjgd
Igdsj`or tbo cgllgwjdm systoa sbgwd jd Cjm. 3.;. Pbjs systoa js ikllo` kd kdklgm-tg-`jmjtkl (K/@) igdvorsjgd systoa. Pbo hksji j`ok gc K/@ igdvorsjgd js tg tkeo kigdtjdugus-tjao sjmdkl, kd` igdvort jt tg k `jsiroto-tjao sjmdkl.
Cjmuro 3.;6 Kd kdklgm tg `jmjtkl (K/@) igdvorsjgd systoa.
Aktboaktjiklly, jc tbo igdtjdugus-tjao sjmdkl js x(t), wo ikd iglloit k sot gc skaploshy aultjplyjdm x(t) wjtb kd japulso trkjd p(t)6
p(t) 1
d1
(t dP),
29
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20 IBK^POX 3. YKA^LJDM PBOGXOA
wboroP js tbo porjg` gc tbo japulso trkjd. Aultjplyjdm x(t) wjtbp(t) yjol`s
xp(t) 1x(t)p(t)
1x(t)
d1(t dP)
1
d1x(t)(t dP)
1
d1x(dP)(t dP).
^jitgrjklly, xp(t) js k sot gc japulsos hgud`o` hy tbo odvolgp x(t) ks sbgwd jd Cjm.3.8.
Cjmuro 3.86 Kd oxkaplo gc K/@ igdvorsjgd. Pbo gutput sjmdkl xp(t) roprosodts k sotgc skaplos gc tbo sjmdkl x(t).
]o aky romkr`xp(t) ks tbo skaplos gcx(t). Dgto tbktxp(t) js stjll k igdtjdugus-tjaosjmdkl! (]o ikd vjow xp(t) ks k `jsiroto-tjao sjmdkl jc wo `odo xpUdQ 1x(dP). Huttbjs js dgt kd japgrtkdt jssuo boro.)
3.8 Croquodiy Kdklysjs gc K/@ Igdvorsjgd
Bkvjdm kd oxplkdktjgd gc tbo K/@ igdvorsjgd jd tjao `gakjd, wo dgw wkdt tg stu`ytbo K/@ igdvorsjgd jd tbo croquodiy `gakjd. (]by7 ]o doo` jt cgr tbo `ovolgp-aodt gc Ykapljdm Pbogroa!) Yg, bgw `g tbo croquodiy rospgdsos R(f),^(f) kd`Rp(f) lgge ljeo7
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3.8. CXO[_ODIZ KDKLZYJY GC K/@ IGDSOXYJGD 2?
3.8.; Bgw `gos ^(f) lgge ljeo7
Lots stkrt wjtb ^(f). Crga Pkhlo 0.8 gc tbo toxthgge, wo edgw tbkt
p(t) 1
d1(t dP) C.P. 8
P
e1
( 8eP
) 1^(f) (3.;)
Pbjs aokds tbkt tbo croquodiy rospgdso gc tbo japulso trkjd p(t) js kdgtbor japulsotrkjd. Pbo gdly `jorodio js tbkt tbo porjg` gcp(t) jsP, wboroks tbo porjg` gc^(f)js 8P .
Cjmuro 3.96 Jllustrktjgd gcR(f) kd`^(f).
3.8.8 Bgw `gos Rp(f) lgge ljeo7
Doxt, suppgso tbkt tbo sjmdkl x(t) bks k croquodiy rospgdsoR(f). ]o wkdt tg edgwtbo croquodiy rospgdso gc tbo gutput xp(t). Crga tbo `odjtjgd gcxp(t), wo edgwedgw tbkt
xp(t) 1x(t)p(t).
Pborocgro, hy tbo aultjpljiktjgd prgporty gc Cgurjor Prkdscgra, wo bkvo
Rp(f) 1 ;
8R(f) ^(f).
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3.8. CXO[_ODIZ KDKLZYJY GC K/@ IGDSOXYJGD 2=
Cjmuro 3.?6 Jllustrktjgd gcxp(t) kd`Rp(f).
japulsos jdiroksos (j.o., ckrtbor kpkrt). Jd croquodiy `gakjd, sjdio
^(f) 18
P
e1( 8e
P ),
tbo porjg` 8P ro`uios! Jd gtbor wgr s, tbo japulsos kro agro pkieo` jd croquodiy`gakjd wbod P jdiroksos. Cjm. 3.3 jllustrktos tbjs j`ok.
Cjmuro 3.36 ]bodPjdiroksos, tbo porjg` jd croquodiy `gakjd ro`uios.
Jc wo igdsj`or Rp(f), wbjib js k porjg`ji ropljikto gcR(f) kt tbo japulsos mjvodhy^(f), wo soo tbkt tbo sopkrktjgd hotwood ropljiktos ro`uios. ]bodP bjts ior-tkjd ljajt, tbo sopkrktjgd hoigaos zorg5 kd` hoygd` tbkt ljajt, tbo ropljiktos stkrt tggvorlkp! ]bod tbo croquodiy ropljiktos gvorlkp, wo sky tbkt tboro js kljksjdm.
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3.9. YKA^LJDM PBOGXOA 2:
Cjmuro 3.:6 Loct6 K hkd` ljajto` sjmdkl (sjdio R(f) 1 > cgr kll 4 |]|.) Xjmbt6 Khkd` dgd-ljajto` sjmdkl.
3.9 Ykapljdm Pbogroa
Pbogroa ;;(Ykapljdm Pbogroa). Lotx(t)ho k hkd` ljajto` sjmdkl wjtbR(f) 1 >cgr kll|| 4 ]. Pbod tbo ajdjaua skapljdm rkto suib tbkt dg kljksjdm giiurs jdRp(f) js
s 4 8],
wboros1 8P
.
3.9.; Oxplkdktjgd
Yuppgso x(t) bks hkd`wj`tb]. Pbo tjmbtost krrkdmoaodt tbkt dg kljksjdm giiurs jssbgwd jd Cjm. 3.;>
Cjmuro 3.;>6 Ajdjaua skapljdm rkto tbkt tboro js dg kljksjdm.
Jd tbjs ikso, wo soo tbkt tbo skapljdm rkto s (1 8P
) js
s 1 8].
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:> IBK^POX 3. YKA^LJDM PBOGXOA
JcP js lkrmor (gr s js sakllor), tbod 8P hoigaos loss tbkd 8], kd` kljksjdm giiurs.
Pborocgro, tbo ajdjaua skapljdm rkto tg odsuro dg kljksjdm js
s 4 8].
3.9.8 Oxkaplo
Yuppgso tboro js k sjmdkl wjtb akxjaua croquodiy 0>eBz. ]bkt js tbo ajdjauaskapljdm rkto 7
Cjmuro 3.;;6 Oxkaplo6 Ajdjaua skapljdm croquodiy.
Kdswor 6Yjdio 1 8c, wo edgw tbkt tbo akx croquodiy (jd rk`) js 1 8(0> ;>9) 12>
;>9 (rk`). Pborocgro, tbo ajdjaua Ykapljdm rkto js6 8
(2>
;>9), wbjib js
;3> ;>9 (rk`) 1 2>eBz.
3.0 @jmjtkl tg Kdklgm Igdvorsjgd
Jd tbo provjgus soitjgds, wo stu`jo` K/@ igdvorsjgd. Dgw, mjvod k `jsiroto-tjaosjmdkl (kssuao dg kljksjdm), wo wgul` ljeo tg igdstruit tbo igdtjdugus tjao sjmdkl.
3.0.; Mjvod Rp(t) (dg kljksjdm), bgw `g J roigvor x(t)7
Jc dg kljksjdm giiurs `urjdm tbo skapljdm prgiossjdm (j.o., aultjply x(t) wjtb p(t)),tbod wo ikd kpply k lgwpkss ltor B(f) tg oxtrkit tbo x(t) crga xp(t). Cjm. 3.;8sbgws k siboaktji `jkmrka gc bgw tbjs js porcgrao`.Pg soo bgw kd j`okl lgwpkss ltor ikd oxtrkit x(t) crga xp(t), wo rst lgge kt tbocroquodiy rospgdso gcRp(f). Yuppgso tbktp(t) bks k porjg` gcP(sg tbkts1
8P).
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3.0. @JMJPKL PG KDKLGM IGDSOXYJGD :;
Cjmuro 3.;86 Yiboaktji `jkmrka gc roigvorjdm x(t) crga xp
(t). Pbo ltor B(f) jskssuao` tg ho kd j`okl lgwpkss ltor.
Pbod
Rp(f) 1 ;
P
R(f( es)).
Ks sbgwd jd tbo tgp loct gc Cjm. 3.;9, Rp(f) js k porjg`ji ropljikto gcR(f). Yjdiowo kssuao tbkt tboro js dg kljksjdm, tbo ropljikto igvorjdm tbo y-kxjs js j`odtjikl tgR(f). Pbkt js, cgr|| < s8,
Rp(f) 1R(f).
Dgw, jc wo kpply kd j`okl lgwpkss ltor (sbgwd jd hgttga loct gc Cjm. 3.;9)6
B(f) 1
;, || < s8,>, gtborwjso,
tbodRp(f)B(f) 1R(f),
cgr kll . Pkejdm tbo jdvorso igdtjdugus-tjao Cgurjor trkdscgra, wo ikd ghtkjd x(t).
3.0.8 JcRp(t) bks kljksjdm, ikd J stjll roigvor x(t) crga xp(t) 7
Pbo kdswor js DG. Jc kljksjdm giiurs, tbod tbo igd`jtjgd
Rp(f) 1R(f)
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:8 IBK^POX 3. YKA^LJDM PBOGXOA
Cjmuro 3.;96 Loct6 Aultjpljiktjgd hotwood Rp(f) kd` tbo lgwpkss ltor B(f). Pbo
oxtrkito` gutput R(f) js j`odtjikl tg R(f) jc dg kljksjdm giiurs. Hy kpplyjdm
jdvorso Cgurjor trkdscgra tg R(f) wo ikd ghtkjd x(t).
`gos dgt bgl` cgr kll || < s8. Igdsoquodtly, ovod jc wo kpply tbo lgwpkss ltorB(f)tgRp(f), tbo rosult js dgt R(f). Pbjs ikd ho sood jd Cjm. 3.;0.
Cjmuro 3.;06 Jc kljksjdm giiurs, wo kro udkhlo tg roigvor x(t) crga xp(t) hy usjdm kdj`okl lgwpkss ltor.
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3.0. @JMJPKL PG KDKLGM IGDSOXYJGD :9
3.0.9 ]bkt ikd J `g jc ay skapljdm `ovjio `gos dgt suppgrt
k vory bjmb skapljdm rkto 7 Aotbg` ;6 Huy k hottor skapljdm `ovjio ! Aotbg` 86 Yod` sjmdkls wjtb dkrrgwor hkd`wj`tb gr ljajt tbo hkd`wj`tb ho-
cgro sod`jdm 6
Aotbg` 96 Mg tg mrk` sibggl kd` lokrd agro iggl aotbg`s !!
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:0 IBK^POX 3. YKA^LJDM PBOGXOA
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Ibkptor =
Pbo z-Prkdscgra
Pboz-trkdscgra js k modorkljzktjgd gc tbo `jsiroto-tjao Cgurjor trkdscgra wo lokrdo`jd Ibkptor ?. Ks wo wjll soo, z-trkdscgra kllgws us tg stu`y sgao systoa prgportjostbkt @PCP ikddgt `g.
=.; Pbo z-Prkdscgra
@odjtjgd 8;. Pboz-trkdscgra gc k `jsiroto-tjao sjmdklxUdQ js6
R(z) 1
d1 xUdQzd. (=.;)
]o `odgto tboz-trkdscgra gporktjgd ks
xUdQ R(z).Jd modorkl, tbo duahorzjd (=.;) js k igaplox duahor. Pborocgro, wo aky wrjto zks
z1 rofw ,
wboror X kd` w X. ]bodr1 ;, (=.;) hoigaos
R(ofw) 1
d1xUdQofwd ,wbjib js tbo `jsiroto-tjao Cgurjor trkdscgra gcxUdQ. Pborocgro, @PCP js k spoijklikso gc tbo z-trkdscgra! ^jitgrjklly, wo ikd vjow @PCP ks tbo z-trkdscgra ovklukto`gd tbo udjt ijrilo6
:?
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=.;. PBOV-PXKDYCGXA :=
Oxkaplo ;. Igdsj`or tbo sjmdkl xUdQ 1kduUdQ, wjtb >< k
kz;
d.
Pborocgro, R(z) igdvormos jc
d1>(kz;)d
rz;
d1
;
; kz; ,
wbod|kz;|
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:2 IBK^POX =. PBOV-PXKDYCGXA
Oxkaplo 8. Igdsj`or tbo sjmdkl xUdQ 1kduUd ;Q wjtb > < k < ;. Pbo
z-trkdscgra gcxUdQ js
R(z) 1
d1kduUd ;Qzd
1 ;
d1kdzd
1 d1;
kdzd
1 ;
d1>
k;zd .Pborocgro,R(z) igdvormos wbod|k;z|
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=.;. PBOV-PXKDYCGXA ::
Oxkaplo 9. Igdsj`or tbo sjmdkl
xUdQ 1 =
;
9
duUdQ 3
;
8
duUdQ.
Pboz-trkdscgra js
R(z) 1
d1
=
;
9
d 3
;
8
duUdQzd
1 = d1
;9d uUdQzd 3
d1;
8d uUdQzd
1 =
;
; ;9z;
3
;
; ;8z;
1 ; 98z;
; ;9z;
; ;8z; .
Cgr R(z) tg igdvormo, hgtb suas jd R(z) aust igdvormo. Yg wo doo` hgtb|z| 4 |;9|
kd`
|z
|4
|;8
|. Pbus, tbo XGI js tbo sot gczsuib tbkt
|z
|4
|;8
|.
Cjmuro =.06 ^glo-zorg plgt kd` XGI gc Oxkaplo 9.
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;>> IBK^POX =. PBOV-PXKDYCGXA
=.8 z-trkdscgra ^kjrs
=.8.; K. Pkhlo ;>.8
;. UdQ ;, kll z8. Ud aQ za, kllzoxiopt > wbod a 4> kd`wboda .9. uUdQ ;
;z; ,|z| 4;
0. kduUdQ ;;kz; ,|z| 4 k
?.kduUd ;Q ;;kz; ,|z| < |k|.
Oxkaplo 0. Lot us sbgw tbkt UdQ ;. Pg soo tbjs,
R(z) 1
d1xUdQzd 1
d1
UdQzd
1
d1UdQ 1 ;.
Oxkaplo ?. Lots sbgw tbkt Ud aQ za6
R(z) 1
d1
xUdQzd 1
d1
Ud aQzd
1za
d1Ud aQ 1za.
=.8.8 H. Pkhlo ;>.;
;. kx;UdQ +hx8UdQ kR;(z) +hR8(z)8. xUd d>Q R(z)zd>
9. zd> xUdQ R( zz> )0. ofw>dxUdQ R(ofw>z)?. xUdQ R(;z )
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=.8. V-PXKDYCGXA ^KJXY ;>;
3. xUdQ R(z)
=. x;UdQ x8UdQ R;(z)R8(z)
2. Jcy UdQ 1
xUd/LQ, djs aultjplos gcL
>, gtborwjso,
tbodZ(z) 1R(zL).
Oxkaplo 3. Igdsj`or tbo sjmdklbUdQ 1UdQ + Ud ; Q + 8Ud 8Q. Pboz-PrkdscgragcbUdQ js
B(z) 1 ; +z; + 8z8.
Oxkaplo =. Lot prgvo tbkt xUdQ R(z;
). Lottjdm y UdQ 1xUdQ, wo bkvo
Z(z) 1
d1yUdQzd 1
d1
xUdQzd
1
a1
xUaQza 1R(;/z).
Oxkaplo 2. Igdsj`or tbo sjmdkl xUdQ 1;9
sjd
0
d
uUdQ. Pg d` tbo z-Prkdscgra,wo rst dgto tbkt
xUdQ 1 ;8f
;9
of 0d uUdQ ;8f
;9
of 0d uUdQ.Pboz-Prkdscgra js
R(z) 1
d1xUdQzd
1
d1>
;
8f
;
9of
0 z;
d
d1>
;
8f
;
9of
0 z;
d1
;
8f
;
; ;9of
0 z; ;
8f
;
; ;9of
0 z;
1
;98
z;
(; ;9
of0 z;)(; ;
9of
0 z;)
.
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=.9. ^XG^OXPJOY GC XGI ;>9
hoikuso r> < ; mukrkdtoos tbkt tbo sua js djto.
Dgw, jc tboro js kdgtbor pgjdt z wjtb|z| 1r; 4 r>, wo aky wrjto r; 1 kr> cgr sgaok 4;. Pbod tbo sorjos
d1D;
xUdQrd; 1
d1D;
xUdQkdrd>
kD;
d1D;
xUdQrd> < .
Yg, z js klsg jd tbo XGI.
^rgporty =. JcR(z) js rktjgdkl, j.o., R(z) 1 K(z)H(z)
wboroK(z) kd`H(z) kro pgly-
dgajkls, kd` jcxUdQjs rjmbt-sj`o`, tbod tbo XGI js tbo romjgd gutsj`o tbo gutoragstpglo.
^rggc. JcR(z) js rktjgdkl, tbod hy (Kppod`jx, K.?=) gc tbo toxthgge
R(z) 1 K(z)
H(z)1
d;e1>kez
e
re1;(; p;e z)e
,
wborope js tbo e-tb pglo gc tbo systoa. _sjdm pkrtjkl crkitjgd, wo bkvo
R(z) 1r
j1;
je1;
Ije
(; p;j z)e.
Okib gc tbo tora jd tbo pkrtjkl crkitjgd bks kd XGI hojdm tbo sot gc z suib tbkt|z| 4|pj| (hoikuso xUdQ js rjmbt-sj`o`). Jd gr`or tg bkvo R(z) igdvormodt, tbo XGIaust ho tbo jdtorsoitjgd gc kll jd`jvj`ukl XGIs. Pborocgro, tbo XGI js tbo romjgdgutsj`o tbo gutoragst pglo.
Cgr oxkaplo, jc
R(z) 1 ;
(; ;9z;)(; ;8z;),
tbod tbo XGI js tbo romjgd|z| 4 ;8 .
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;>0 IBK^POX =. PBOV-PXKDYCGXA
=.0 Yystoa ^rgportjos usjdmz-trkdscgra
=.0.; Ikuskljty
^rgporty 2. K `jsiroto-tjao LPJ systoa js ikuskl jc kd` gdly jc XGI js tbo oxtorjgrgc k ijrilo (jdilu`jdm).
^rggc. K systoa js ikuskl jc kd` gdly jc
bUdQ 1 >, d .
Pborocgro,bUdQ aust ho rjmbt-sj`o`. ^rgporty ? japljos tbkt XGI js gutsj`o k ijrilo.
Klsg, hy tbo `odjtjgd tbkt
B(z) 1d1>
bUdQzd
wboro tboro js dg pgsjtjvo pgwors gcz, B(z) igdvormos klsg wbod z (Gc igurso,|z| 4; wbod z !).
=.0.8 Ytkhljljty
^rgporty :. K `jsiroto-tjao LPJ systoa js stkhlo jc kd` gdly jc XGI gc B(z)jdilu`os tbo udjt ijrilo.
^rggc. K systoa js stkhlo jc kd` gdly jcbUdQ js khsglutoly suaakhlo, jc kd` gdly jc@PCP gcbUdQ oxjsts. Igdsoquodtly hy ^rgporty 8, XGI gcB(z) aust jdilu`o tboudjt ijrilo.
^rgporty ;>. K ikuskl `jsiroto-tjao LPJ systoa js stkhlo jc kd` gdly jc kll gc jtspglos kro jdsj`o tbo udjt ijrilo.
^rggc. Pbo prggc cgllgws crga ^rgporty 2 kd` : `jroitly.
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