signals and system - stanley chan

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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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