nyuuzyou/kompy huggingface dataset:
Taktli sinxronizatsiya tarmoqlarida asosiy
boshqarish sxemalari

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Taktli sinxronizatsiya tarmoqlarida asosiy
boshqarish sxemalari
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bet | 15/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)Taktli sinxronizatsiya tarmoqlarida asosiy
boshqarish sxemalari
Sinxronizatsiyaning asosiy masalalari va asosiy tushunchalari xalqaro elektraloqa ittifoqi (XEI) G.810 [6] tavsiyalarida berilgan, ular raqamli TOAT uchun dolzarbdir.
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Taktli sinxronizatsiyaning maqsadi — birlamchi taktli interval uzunligi to yoki taktli chastota fo haqidagi axborotlarni bir tarmoqning barcha qurilma/tugunlariga yoki barcha o'zaro ta’sir- lashuvdagi tarmoqlarga talab etiladigan aniqlikda uzatishdan iborat. Bu maqsadga erishish tarmoq operatoriga sinxronizatsiya man- bayining berilgan aniqligi uchun tanlangan vaqt oralig‘ida minimum yuzaga kelishi mumkin bo'lgan sliplar soni haqida axborotga ega bo'lish imkonini beradi. Bu barcha tarmoq tugunlarida eng yuqori sifatli saqlovchi manba yoki taymerni o'rnatish bilan barobar.
Ko‘rsatilgan masalani soddalashtirish mumkin: tarmoqning inarkaziy tugunida bitta yuqori aniqlikli generatomi o‘matish va bosliqa tarmoq tugunlarida uning ko'rsatkichlarini translyatsiya qilish hamda ko'paytirish.
Btiniiig uchun nal’aqat yuqori aniqlikdagi birlamchi generatorga, ba Ik i isl unichli sinxronizatsiya signalini taqsimlovchi tizim (SSTT)ga ham cga bo'lish kerak.
Agar tarmoq katta bo‘lsa, u (sinxronizatsiya maqsadiga erishish uchun) bir necha regional tarmoqlarga bo‘linishi mumkin, har bir regional tarmoqda birlamchi generator o‘rnatiladi va sinxronizatsiya signalini taqsimlash xizmati tashkil etiladi. Bu tizim TTSning uch muqobil sxemalari bo'yicha tuzilishi mumkin (1.13- rasm):
bir sathli yulduzcha sxemasi (1.13-a rasm), bunda tarmoqning hamma tugunlari taktli impulslaming (yulduzcha markazida joylashgan) birlamchi etalon generator (BEG) (uni birinchi sathli saqlovchi manba deb ataymiz) manbayi bilan ta’minlanadi;
O — tarmoqning sinxronizatsiyalanadigan tugunlari, SB— sinxronizatsiya bloklari, MChBG — mahalliy chastota beruvchi generator);
bir sathli taqsimlangan sxema (1.13-b rasm), bunda har bir (yoki har bir ikkinchi) tarmoq tuguni BEG yoki uning ekvivalenti — BEG signallarini qabul qilgich (masalan, GLONASS yoki GPS tizim) bilan jihozlanadi;
iyerarxik ko‘p sathli sxema (1.13-d rasm)da BEG (iyerar- xiyaning birinchi sathi) joylashtiriladigan, bazaviy nuqta aniqlanadi. BEG signallari daraxtsimon sinxronizatsiya tarmog‘ining sinxronizatsiyalanadigan elementlari (SE) bo'ylab ikkilamchi iyerar-
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12-laboratoriya ishi kerio control yordamida vpn asosida xavfsiz tarmoqni qurish ishdan maqsad

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12-laboratoriya ishi kerio control yordamida vpn asosida xavfsiz tarmoqni qurish ishdan maqsad
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Sana | 20.05.2024 | Hajmi | 2,42 Mb. | | #244807 |
MUHAMMAD AL-XORAZMIY NOMIDAGI TOSHKENT AXBOROT TEXNOLOGIYALARI UNIVERSITETI
TELEKOMMUNIKATSIYA TEXNOLOGIYALARI
FAKULTET
Virtual tarmoq texnologiyasi
Labaratoriya ishi -12
Talaba guruhi: 415-20
Bajardi: Norqulov Aslbek
Tekshirdi: Temirova Dilfuza
12-LABORATORIYA ISHI
KERIO CONTROL YORDAMIDA VPN ASOSIDA XAVFSIZ
TARMOQNI QURISH
Ishdan maqsad
Kerio Control dasturiy ta’minoti asosida VPN tarmog‘ini qurish bo‘yicha
amaliy ko‘nikmalarga ega bo‘lish.
Qisqa nazariy ma’lumotlar
VPN yoki Virtual Private Network atamasi ingliz tilidan – virtual xususiy
tarmoq ma’nosini anglatadi. Oddiy so‘zlar bilan ifodalanganda, bu – mavjud aloqa
ustidan tonnel ko‘rinishidagi alohida shifrlangan tarmoqni yaratuvchi texnologiya.
Masalan, internet tarmog‘i ustidan. VPN, faqatgina ma’lum foydalanuvchilar kirishi
mumkin bo‘lgan izolyatsiyalangan tarmoq bo‘lishi ham mumkin.
VPN tarmoqda anonimlikni saqlab qolish imkonini beradi. VPN orqali siz
kiradigan saytlarga ulanishda, sizning joylashgan joyingiz, brauzer ma’lumotlari va
boshqa shaxsiy ma’lumotlarni kuzatish imkoni bo‘lmaydi. Masalan, siz ta’tilga “N”
nomli mamlakatga dam olishga borishingiz mumkin. Bu davlatda Telegram va
YouTube taqiq ostida bloklangan bo‘lishi mumkin.
Interfeys bo`limi
Vpn server sozlanishi
Trafik qoidalari
Userlar bo`limi
Foydalanuvchini o`zgartirish
Ip manzil biriktirish
Yangi VPN ulanish
Ulanish usulini tanlash
Tarmoq adresini kiritish
Foydalanuvchi nomi va parolini kiritish
Ulanish natijasi
“Безопасность” bo‘limi
XULOSA:
VPN-server, yoki Virtual Private Network serveri, internetdagi xavfsiz aloqa kanalini yaratish uchun ishlatiladigan maxsus serverdir. VPN-server orqali foydalanuvchilar va tarmoqlar o'rtasida shifrlangan tunel o'rnatiladi, bu esa foydalanuvchilarga Internetti xavfsiz va anonim tarzda ishlatishga imkon beradi. VPN foydalanuvchilarini Internetdagi potentsial xavflardan himoya qilish bilan birga, geografik cheklovlarni chetlab o'tish, masofadan turib korporativ tarmoqlarga xavfsiz kirish va Internetdagi maxfiy ma'lumotlarni himoyalash uchun keng qo'llaniladi. VPN-server saytga yoki tarmoq resurslariga shifrlangan, xavfsiz va xususiy ulanishni taqdim etadi.
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Vaqt bo‘yicha zichlashtirish

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Vaqt bo‘yicha zichlashtirish
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bet | 11/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)Vaqt bo‘yicha zichlashtirish. Bu usulda bir necha informatsion oqimlarni bitta oqimga birlashtirish nazarda tutiladi. Birlashtirish elektrik signallar va optik signallar darajasida amalga oshirilishi mumkin. 1.9-rasmda elektr signallar darajasida vaqt bo‘yicha zichlashtirilgan TOAT liniya traktining tuzilish sxemasi ko‘rsatilgan
A va В kirishdan tushayotgan elektr signallarning ikki qism impulslari (Amanba bo‘lishi mumkin) birlashtiruvchi qurilma (BQ) yordamida vaqt bo‘yicha aniq ketma-ketlikka ega guruhli signalga birlashtiriladi. Guruhli signal optik uzatkich (OUz) da optik tashuvchini modulyatsiyalaydi. Optik nurlanish (ОТ) bo‘ylab tarqaladi va optik qabul qilgich (OQq) da qaytadan elektr signaliga o‘zgartiriladi. So‘ng bu signal ajratuvchi qurilma (AQ) yordamida A' va chiqishlariga beriladigan impulslarga ajratiladi.
1.9-rasm. Elektr signallar darajasida vaqt bo‘yicha zichlashtirilgan
TOATning liniya trakti
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iiijiKjOiiijubijiiji
rasmda optik va raqamli oqimlarning birlashtirish sxemasi ko‘rsatilgan.
1.10-rasm. Optik signallar darajasida vaqt bo‘yicha zichlashtirilgan
TOATning liniya trakti
Amanbadan elektrik raqamli oqimlar TV optik uzatkich OUz ga tushadi. OUz da elektr signallar optik signallarga o'zgartiriladi. Optik signallarni birlashtirishdan oldin ularni At; 2 At; 3At; (TV — l)At ga kechikishi ro‘y beradi. Bunday kechikishdan keyin optik siljitkich (OS) chiqishida optik impulslar ketma-ketligiga egabo‘lamiz. Qabul qilishda bunga teskari jarayon amalga oshiriladi.
Vaqt bo‘yicha zichlashtirishda qisqa (10'9C va undan kichik) yorug‘lik impulslarini uzatish talab etiladi. Lekin subnanosekundli impulslarni uzatish TOAT uzatib qabul qiluvchi apparaturalarining optoelektron qurilmalarining oxirgi imkoniyatiga yaqin bo‘lgan tezkorligiga juda yuqori talablar qo‘yadi. Bundan tashqari, optik tolaning dispersiya xususiyatlari tufayli uzatish tezligi, o‘tkazish oralig‘i ham chegaralangan. Vaqt bo‘yicha zichlashtirishning asosiy afzalligi bu ОТ o‘tkazish qobiliyatidan samarali foydalanish koeffitsiyentining ortishi va to‘liq optik aloqa tarmoqlarini yaratish imkoniyatining mavjudligi hisoblanadi.
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-bob. Optik attenyuator, optik filtrlar, izolator va
sirkulatoriar

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-bob. Optik attenyuator, optik filtrlar, izolator va
sirkulatoriar
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bet | 158/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)8-bob. Optik attenyuator, optik filtrlar, izolator va
sirkulatoriar
Optik attenyuatorlar 227
Optik filtrlar 228
Optik izolatorlar 234
Optik sirkulatoriar 238
9-bob. Optik multipleksoriar va
demultipleksorlar
Optik multpleksorva demultipleksorlar, ulaming turlari 241
Yupqa pardali filtrlar asosidagi optik multipleksoriar/ demultipleksorlar 243
Difraktsiya panjaralaridan foydalanishga asoslangan optik multipleksor /demultipleksorlar 245
Tolali bregg panjaralari asosidagi optik multipleksoriar 248
Optik multipleksor/demultipleksorlardan foydalanishga oid ayrim masalalar 250
Tolali optik aloqa tizimlarida invers multipleksorlash 251
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10-bob. Optik kommutatorlar
Asosiy tushunchalar 254
Optik kommutatorlaming asosiy vazifalari 255
Optik kommutatorlaming asosiy parametrlari 255
Optik kommutatorlaming asosiy turlari 256
Katta o'lchamli optik kommutatorlaming tuzilishi 259
Foydalanilgan adabiyotlar 272
4-bo‘lim. TOLALI OPTIK ALOQA TIZIMLARINING
LINIYA TRAKTI
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-bob. Optik aloqa tizimlarida qo'llaniladigan
fotoqabulqilgichlar

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-bob. Optik aloqa tizimlarida qo'llaniladigan
fotoqabulqilgichlar
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bet | 156/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)4-bob. Optik aloqa tizimlarida qo'llaniladigan
fotoqabulqilgichlar
Tolali optik aloqa tizimida qo'llaniladigan fotoqabulqilgichlarga qo'yiladigan talablar 128
Yarim o'tkazgichli fotoqabulqilgichlarning turlari, ulaming asosiy xarakteristikalari va parametrlari 129
Fotodiod, uning tuzilishi, ish mexanizmi, xarakteristikalari va parametrlari...131
p-i-n fotodiodi 136
Gctcroo'tishli fotodiod 139
Shottki to'siqli fotodiod 141
Ko'chkili fotodiod 143
Fototranzistorlar 146
Optik uzatish tizimlarida qo'llaniladigan fotoqabulqilgich turlarining qiyosiy tavsifi 150
Tolali optik aloqa tizimlarining optoelektron qabul qiluvchi moduli va uning tarkibiy qurilmalari 155
5-bob. Optik kuchaytirgichlar
Optik kuchaytitgich va uning turlari 158
Aralashmali tolalar optik kuchaytirgichlar, ulaming tuzilishi ish mexanizmi, xarakteristika va parametrlari 159
Yorag'likning Raman sochilishiga asoslangan optik kuchaytirgichlar 168
Yarimo'tkazgichli optik kuchaytirgichlar, ularning • xarakteristika va parametrlari ' 170
Optik kuchaytirgichlaming qiyosiy tafsivi 174
Optik kuchaytirgichlaming paramctrlarini aniqlash va hisoblash usullari 177
Optik kuchaytirgichlami qo'llash usullari 180
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-bob. Raqamli tolali optik aloqa tizimlarining liniya trakti

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-bob. Raqamli tolali optik aloqa tizimlarining liniya trakti
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bet | 159/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)11-bob. Raqamli tolali optik aloqa tizimlarining liniya trakti
Raqamli tolali optik aloqa tizimlarining liniya traktida qo‘llaniladigan asosiy qurilmalar. Retranslyatorlar, ulaming turlari: regenerator va optik kuchaytirgichlar 275
Optik signallarni regeneratsiyalash. Regeneratorning tuzilishi va ish prinsipi 277
Raqamli tolali optik aloqa tizimlarining liniya kodlari 282
Foydalanilgan adabiyotlar 294
5-bo‘lim. TOLALI OPTIK ALOQA TARMOQLARI
12-bob. Tolali optik aloqa tarmoqlari
Infokommunikatsion xizmatlar 295
Optik aloqa tarmoqlariga qo'yiladigan talablar 296
Optik aloqa tarmoqlarining turlari 297
Optik aloqa tarmoqlari 299
Optik kommutatorlar asosida optik aloqa tarmoqlarini tuzish prinsiplari 315
Foydalanilgan adabiyotlar 325
6-bo‘lim. TOLALI OPTIK ALOQA TIZIMLARI VA
TARMOQLARINI TEXNIK EKSPLUATATSIYA QILISH
13-bob. Tolali optik aloqa tizimlari va tarmoqlarini texnik ekspluatatsiya
qilish va boshqarishni tashkil etish bo'yicha asosiy qoidalar
Texnik ekspluatatsiya jarayonini tashkil etish 326
Texnik ekspluatatsiya va boshqarish tizimini tashkil etish 335
Foydalanilgan adabiyotlar 347
7-bo‘lim.
14-bob. Optik aloqa tizimlarining rivojlanish tamoyillari
va istiqbollari
14.1. To'liq foton texnologiyasiga asoslangan aloqa tizimlari vatarmoqlarini yaratishga qaratilgan ishlanmalar 349
Foydalanilgan adabiyotlar ro'yxati 363
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To‘Iqin uzunligi bo‘yicha zichlashtirish

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To‘Iqin uzunligi bo‘yicha zichlashtirish
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bet | 13/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)To‘Iqin uzunligi bo‘yicha zichlashtirish. Optik tolaning o‘tkazish qobiliyatidan samarali foydalanish koeffitsiyentini oshirishning istiqbolli yo'nalishlaridan biri to‘lqin uzunligi bo'yicha zichlash- tirishdir. 1.8 -rasmda to‘lqin uzunligi bo‘yicha zichlashtirish usuli tasvirlangan edi. Bunda liniya kabelidagi bir optik tola orqali ko‘plab axborotlarni uzatish hisobiga sezilarli darajada iqtisodiy samara- dorlikka erishiladi. Bundan tashqari, bu usul qo‘shimcha qurilish ishlarisiz tarmoq rivojlanishini ta’minlash, shuningdek, tarmoq- langan daraxtsimon va halqali tarmoqlarni tuzish imkonini beradi. Bunda har xil tezlikli, raqamli va analog turli modulyatsiyali (telefon, televideniye, telemetriya, boshqarish) signallarni uzatish imkoniyati kengayadi. Bu esa iqtisodni tejovchi ko‘p funksiyali aloqa tizimlarini tashkil etishni ta’minlaydi.
Optik tolaning spektral o'tkazish oralig‘idan birmuncha to‘liq foydalanish bu usulning eng muhim afzalliklaridan biri hisoblanadi. Hozirgi kunda 0,8.... 1,8 mkm diapazon oralig‘i o'rganilgan. Agarda spektral kanalning kengligi 10 nm ni tashkil etsa, u holda belgilangan diapazonda 100 tagacha spektral kanallarni joylashtirish mumkin.
To‘lqin uzunligi bo‘yicha zichlashtirilgan TOATda so'nish va dispersiya qiymatlari kichik bo'lgan bir modali optik tolalar hamda quwati yuqori lazer nurlanish manbalaridan foydalanish maqsadga muvofiqdir. Foydalaniladigan bir modali optik tola 1,5... 1,6 mkm to‘lqin uzunligida ishlashi va kvars shishasidan tayyorlangan bo‘lishi kerak.
To‘lqin uzunligi bo‘yicha zichlashtirilgan TOATda uzatishda optik kanallarni birlashtirish uchun optik multipleksor va qabul qilishda optik kanallarni ajratish uchun optik demultipleksor ishlatiladi.
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Panjara va prizmali qurilmalar kanallarni parallel ajratuvchi, filtrlar va selektiv fotodiodli qurilmalar esa kanallarni ketma-ket ajratuvchi hisoblanadi.
To'lqin uzunligi bo'yicha zichlashtiriladigan tizimlar tarkibiga kiradigan demultipleksorlarning tuzilishi, nurning teskari yo‘nalishda tarqalishida spektral-sezgir multipleksorlarning tuzilishiga o‘xshash.
Multipleksor va demultipleksorlar signallarning so‘nishiga sezilarli ta’sir qiladi. Shuning uchun ular optik kuchaytirgichlar bilan birga qo‘llaniladi.
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б-bob. Optik modulyatorlar

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б-bob. Optik modulyatorlar
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bet | 157/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)б-bob. Optik modulyatorlar
Yorug'lik oqimini ichki va tashqi modulyatsiyalash usullari 182
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Yomg‘lik nurlanishini modulyatsiyalashning fizik asoslari 187
Optik modulyator va uning turlari 191
Elektroptik modulyatorlar 192
Akustooptik modulyatorlar 197
Magnitooptik modulyatorlar 199
4. Yupqa pardali va yarimo'tkazgichli modulyatorlar 199
Spektr bo'yicha zichlashtirilgan optik aloqa tizimlarida modulyatsiyalash jarayoni 202
Intensivlik bo‘yicha modulyatsiyalangan optik signalni fotoqabulqilgich tomonidan qabul qilish jarayonlari va ularni bahoiash usullari 203
Foydalanilgan adabiyotlar 208
3-bo‘lim. TOLALI OPTIK ALOQA TIZIMLARINING
PASSIV ELEMENTLARI
7-bob. Yorug'lik nurlanishini optik tolaga kiritish va undan
chiqarish qurilmalari. Tolali optik ulagichlar va taraioqiagichlar
Passiv optik qurilmalaming asosiy parametrlari 210
Yorug‘lik nurlanishini optik tolaga kiritish va undan chiqarish qurilmalari 213
Tolali optik ulagichlar va ulaming turlari 214
Optik tarmoqlagichlar: daraxtsimon va yulduzsimon tarmoqlagichlar, shahoblagich 218
Tolali optik tarmoqlagichlaming parametrlari 222
Tolali optik tarmoqlagichlaming qo‘llanilishi 224
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Yorug‘Iikning sinish jarayoni

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Yorug‘Iikning sinish jarayoni
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bet | 22/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)Yorug‘Iikning sinish jarayoni
Optika qonuniyatlari yorug'lik nurining to‘g‘ri chiziqli tarqa- lishi, tola muhiti bilan o‘zaro ta’sirlashuvi va izotroplik xususiyati — muhitda barcha yo'nalishlarda yorug'likning bir xil tarqalishiga (shisha bir turdagi va izotropli muhit hisoblanadi) asoslangan. Bu qonuniyatlarga yorug‘likning qaytish/sinish qonunlari va ularga asoslangan hodisalar talluqli.
Yorug'lik bir materialdan boshqasiga o‘tganda uning tarqalish tezligi o'zgaradi, ya’ni to'lqin nazariyasi nuqtayi nazaridan bu harakat yo‘nalishining o'zgarishiga olib keladi. Bu hodisa — yorug'likning to‘g‘ri yo‘nalishdan og‘ishi sinish deb ataladi.
Sinish hodisasini misollarda ko'rib chiqamiz.
Sinish hodisasiga baliq ovlashda ham duch kelinadi. Suv ostidagi baliqni ko‘rganimizda, uning haqiqiy joylashuvini emas, balki unga yaqin joylashuvini kohamiz (2.9-rasm).
Agar baliqqa pastga vertikal qarasak, yorug‘likning sinishi ro‘y bermaydi va baliqning asl joylashgan joyini ko‘ramiz. Agar unga burchak ostidan qarasak, sinish hisobiga asl joylashgan joyini ko‘rmaymiz, bunda baliq nazaramizdagi ko‘rinishdan chuqurroqda joylashgan bo'ladi [2].
Haqiqiy
joyiashuv
rasm. Yorug'likning sinishi
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Sinish hodisasini prizmada ham ko‘rlsh mumkin (2.10-rasm).
2.10-rasm. Prizmada yorug'likning sinishi
Prizmaga oq yorug‘lik tushirilganda, prizma bu yorug'likni sindiradi va kamalakning turli ranglariga ajraladi. Qizil rang eng kuchli og‘adi va kichik tarqalish tezligiga ega. Sinish prizma kirishida bo‘lganidek, chiqishida ham hosil bo'ladi [2].
Optik toladan signallarning uzatilishida ham yuqorida ко‘rib chiqilgan sinish hodisasi ro‘y beradi. Bu quyida batafsil tushin- tirilgan.
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MUNDARIJA - Optik aloqa asoslari

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Optik aloqa asoslari
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bet | 154/160 | Sana | 13.01.2024 | Hajmi | 1 Mb. | | #136728 |
Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)MUNDARIJA
So‘zboshi 3
1-bo‘lim. OPTIK ALOQA TIZIMLARINING TUZILISH
PRINSIPLARI VA ISH XUSUSIYATLARI
1-bob. Optik aloqa haqida umumiy ma’lumotlar
Optik aloqa rivojining qisqacha tarixi 7
Optik aloqaning afzalliklari 12
Optik aloqa tizimlarining tasnifi 19
Optik aloqa tizimlarining tuzilish prinsiplari 20
Ocltiq optik aloqa tizimining tuzilish prinsipi 23
Tolali optik aloqa tizimining tuzilish prinsipi 25
Ikki tomonlama tolali optik aloqa tizimini tashkil etish usullari 26
Tolali optik aloqa liniyasini zichlashtirish usullari 29
Tolali optik aloqa tizimlarida axborotlar oqimining sinxronlash masalalari 34
2-bob. Optik tola va kabellar
Optik tola va uning tuzilishi 44
Optik tola turlari va ularning tavsiflari. Bir modali
va ko‘p modali optik tolalar. Pog‘onali, gradiyentli va maxsus sindirish ko'rsatgichili optik tolalar 46
Yorug'likning optik tola bo'ylab tarqalish qonuniyatlari 54
Optik toladagi so'nish hodisasi 66
Optik toladagi dispersiya hodisasi va uning turlari 71
Tolali optik kabellar va ularning turlari 79
Foydalanilgan adabiyotlar 80
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Nazorat savollari - Optik aloqa asoslari

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Optik aloqa asoslari
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Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)Nazorat savollari
Optik aloqa tizimlarining rivojlanish tamoyillariga tavsif bering.
To'liq foto texnologiyasiga asoslangan aloqa tizimlari va tarmoqlarini yaratishga qaratilgan ishlanmalarni tavsiflang.
Optik qulf (zatvor)lardan qanday maqsadlarda foydalaniladi?
Perpendikulyar turdagi yorug'lik bilan boshqariladigan qulfning sxemasini chizib ко ‘rsating va ish prinsipini tushuntiring.
362
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Parallel turdagi yurug'lik bilan boshqariladigan qulfning sxemasini chizib ko‘rsating va ish prinsipini tushuntiring.
YorugTik bilan boshqariladigan fazoviy almashlab ulagichning tuzilishi sxemasini chizib ko‘rsating va ish prinsipini tushuntiring.
Yorug‘lik bilan boshqariladigan kommutatorning tuzilishi sxemasini chizib ko‘rsating va ish prinsipini tushuntiring.
Tolali lazerning tuzilishini va ish prinsipini tavsiflang.
Majburiy kombinatsion sochilishga asoslangan tolali lazerlarning tuzilish sxemalari va ish prinsiplarini tushuntiring.
Foydalanilgan adabiyotlar
Скляров O.K. Современные волоконно-оптические системы передачи. Аппаратура и элементы. — М.: SOLON-R, 2001. — 238 с.
Nakatsuhara К, Hisain S. i dr. All — opnical switching in a nonlinear directicnol coupler loaded with Bragg reflection ECOC’99, v.2, Nice, 1999.
Poustie A.J., Blow K.J., Kelly A.E. and Manning R.J. All-optical binary counter. TuC3.1, ECOC’99, Nice, 1999.
Sklyarov O.K. Formirovatel opticheskix impulsov. Patent №1802418, prioritet ot 08.01.1991, zaregistrirovan 13.10.1993.
Игнатов A.H. Оптоэлектронные приборы и устройства — М.: EKOTRENDZ. 2006. - 270 с.
Парамов В.М. и др. Двухчастотный волоконный VKR лазер // Квантовая электроника. 2004. - №3. — С. 213 - 215.
Dawning James N. Fiber optik communication. Publisher: Cengage learning Sep. 2004. —444 p.
Скляров O.K. Волоконно-оптические сети и системы связи: учебное пособие. 2-ое издание, стер СПБ.: Изд-во «Лань». 2010. —272 с.
Кузмичев В.Н., Макковеев В.И., Светилов Ю.В. Зарождение и развитие оптической многоканальной связи // Электросвязь. №6. 2013. стр 9-14.
www.ziyouz.com kutubxonasi
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Oliy va o’rta maxsus ta’lim vazirligi muqimiy nomidagi qo’qon davlat Учебное пособие предназначено для преподавателей и студентов высших учебных заведений по направлению "География" и "Методика преподавания географии", а также для преподавателей предмета географии в средних общеобразовательных 1,11 Mb. 27
-bo‘lim. OPTIK ALOQA TIZIMLARINING AKTIV
ELEMENTLARI

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ELEMENTLARI
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Bog'liq Optik aloqa asoslari (N.Yusupov, R.Isayev)2-bo‘lim. OPTIK ALOQA TIZIMLARINING AKTIV
ELEMENTLARI
3-bob. Optik aloqa tizimlarida qo‘Ilaniiadigan yorug‘lik manbalari
Optik aloqa tizimlarida qo'llaniladigan yorug'lik manbalariga qo'yiladigan talablar va ularning turlari 82
Yorug'lik diodlari 83
Yorug'lik diodi, uning tuzilishi va ish mexanizmi 83
Yorug'lik diodining asosiy xarakteristikalari va parametrlari 84
Yorug'lik diodining xarakteristikalari va parametrlariga tashqi omillaming ta’siri 97 |
. 3.2.4. Getero tuzilishi va super nurlanuvchi yorug'lik diodlari 98 ।
Yorug'lik diodlarining tolali optik aloqa tizimlarida qo'llanilishi 99
Lazer diodlari 101
364
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Kvaut asboblarining ish prinsipiga oid fundamental fizik jarayonlar- cncrgctik sathlarning teskari egallanganligi, majburiy nurlanish 101
Lazcr diodining ish prinsipi 105
Gctcroo'tishli lazer diodlari, ulaming xarakteristikalari va parametrlari 109
Lazcr diodining nurlanish quwatiga tashqi omillarning ta’siri 113
Lazcr diodining turlari 116
Tolali optik aloqa tizimlarida qo‘llaniladigan yorug'lik manbalarining qiyosiy tafsivi 122
Tolali optik aloqa tizimlarining optoelektron uzatuvchi moduli va uning tarkibiy qurilmalari 124
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Conventions Used in This Book

We appreciate, but do not require, attribution. An attribution usually includes the
title, author, publisher, and ISBN. For example: “
Learning Kali Linux
by Ric Messier
(O’Reilly). Copyright 2018 Ric Messier, 978-1-492-02869-7.”
If you feel your use of code examples falls outside fair use or the permission given
above, feel free to contact us at
permissions@oreilly.com
.
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Who This Book Is For - Learning Kali Linux

Who This Book Is For While I hope there is something in this book for readers with a wide variety of experi‐
ences, the primary audience for the book is people who may have a little Linux or
Unix experience but want to see what Kali is all about. This book is also for people
who want to get a better handle on security testing by using the tools that Kali Linux
has to offer. If you are already experienced with Linux, you may skip
Chapter 1
, for
instance. You may also be someone who has done web application testing by using
some common tools but you want to expand your range to a broader set of skills.
The Value and Importance of Ethics A word about ethics, though you will see this come up a lot because it’s so important
that it’s worth repeating. A lot. Security testing requires that you have permission.
What you are likely to be doing is illegal in most places. Probing remote systems
without permission can get you into a lot of trouble. Mentioning the legality at the
top tends to get people’s attention.
Beyond the legality is the ethics. Security professionals who acquire certifications
have to take oaths related to their ethical practices. One of the most important pre‐
cepts here is not misusing information resources. The CISSP certification has a code
of ethics that goes along with it, requiring you to agree to not do anything illegal or
unethical.
Testing on any system you don’t have permission to test on is not only potentially ille‐
gal, but also certainly unethical by the standards of our industry. It isn’t sufficient to
know someone at the organization you want to target and obtain their permission.
You must have permission from a business owner or someone at an appropriate level
of responsibility to give you that permission. It’s also best to have the permission in
writing. This ensures that both parties are on the same page. It is also important to
have the scope recognized up front. The organization you are testing for may have
restrictions on what you can do, what systems and networks you can touch, and dur‐
ing what hours you can perform the testing. Get all of that in writing. Up front. This
is your Get Out of Jail Free card. Write down the scope of testing and then live by it.
Also, communicate, communicate, communicate. Do yourself a favor. Don’t just get
the permission in writing and then disappear without letting your client know what
xii | Preface
you are doing. Communication and collaboration will yield good results for you and
the organization you are testing for. It’s also generally just the right thing to do.
Within ethical boundaries, have fun!
| Chapter 1: Foundations of Kali Linux

Over the years, another difference between distributions has come with the desktop
environment that is provided by default by the distribution. In recent years, distribu‐
tions have created their own custom views on existing desktop environments.
Whether it’s the GNU Object Model Environment (GNOME), the K Desktop Envi‐
ronment (KDE), or Xfce, they can all be customized with different themes and wall‐
papers and organization of menus and panels. Distributions will often provide their
own spin on a different desktop environment. Some distributions, like Elementar‐
yOS, have even provided their own desktop environment.
While in the end the software all works the same, sometimes the choice of package
manager or even desktop environment can make a difference to users. Additionally,
the depth of the package repository can make a difference to some users. They may
want to ensure they have a lot of choices in software they can install through the
repository rather than trying to build the software by hand and install it. Different
distributions may have smaller repositories, even if they are based on the same pack‐
age management utilities and formats as other distributions. Because of dependencies
of software that need to be installed before the software you are looking for will work,
packages are not always mix-and-match between even related distributions.
Sometimes, different distributions will focus on specific groups of users, rather than
being general-purpose distributions for anyone who wants a desktop. Beyond that,
distributions like Ubuntu will even have two separate installation distributions per
release, one for a server installation and one for a desktop installation. A desktop
installation generally includes a graphical user interface (GUI), whereas a server
installation won’t, and as a result will install far fewer packages. The fewer packages,
the less exposure to attack, and servers are often where sensitive information is stored
in addition to being systems that may be more likely to be exposed to unauthorized
users.
Kali Linux is a distribution that is specifically tailored to a particular type of user—
those who are interested in performing security testing or forensics work. Kali Linux,
as a distribution focused on security testing, falls into the desktop category, and there
is no intention to limit the number of packages that are installed to make Kali harder
to attack. Someone focused on security testing will probably need a wide variety of
software packages, and Kali loads their distribution out of the gate. This may seem
mildly ironic, considering distributions that focus on keeping their systems safe from
attack (sometimes called
secure
) tend to limit the packages. Kali, though, is focused
on testing, rather than keeping the distribution safe from attack.
Wireless Security Testing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

Cross-Site Scripting 250
Cross-Site Request Forgery 251
Session Hijacking 253
Using Proxies 255
Burp Suite 255
Zed Attack Proxy 259
WebScarab 265
Paros Proxy 266
Proxystrike 268
Automated Web Attacks 269
Recon 269
Vega 272
nikto 274
dirbuster and gobuster 276
Java-Based Application Servers 278
SQL-Based Attacks 279
Assorted Tasks 283
Summary 285
Useful Resources 285
9.
Cracking Passwords. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 287
Password Storage 287
Security Account Manager 289
PAM and Crypt 290
Acquiring Passwords 291
Local Cracking 294
John the Ripper 296
Rainbow Tables 298
HashCat 304
Remote Cracking 306
Hydra 306
Patator 308
Web-Based Cracking 309
Summary 313
Useful Resources 313
Looking for Vulnerabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115

|
Looking for Vulnerabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115Bog'liq learningkalilinux4.
Looking for Vulnerabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
Understanding Vulnerabilities 116
Vulnerability Types 117
Buffer Overflow 117
Race Condition 119
Input Validation 120
Access Control 120
Local Vulnerabilities 121
Using lynis for Local Checks 122
iv | Table of Contents
OpenVAS Local Scanning 124
Root Kits 126
Remote Vulnerabilities 128
Quick Start with OpenVAS 129
Creating a Scan 132
OpenVAS Reports 135
Network Device Vulnerabilities 139
Auditing Devices 139
Database Vulnerabilities 142
Identifying New Vulnerabilities 143
Summary 146
Useful Resources 147
5.
Automated Exploits. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 149
What Is an Exploit? 150
Cisco Attacks 151
Management Protocols 152
Other Devices 153
Exploit Database 155
Metasploit 157
Starting with Metasploit 158
Working with Metasploit Modules 159
Importing Data 161
Exploiting Systems 165
Armitage 168
Social Engineering 170
Summary 173
Useful Resources 173
6.
Owning Metasploit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 175
Scanning for Targets 176
Port Scanning 176
SMB Scanning 180
Vulnerability Scans 181
Exploiting Your Target 182
Using Meterpreter 185
Meterpreter Basics 185
User Information 186
Process Manipulation 189
Privilege Escalation 192
Pivoting to Other Networks 196
Maintaining Access 199
Table of Contents | v
Summary 202
Useful Resources 203
|
|
Bosh sahifa
Aloqalar
Bosh sahifa
Looking for Vulnerabilities. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 115
|
ix
     
What This Book Covers

What This Book Covers
Given that the intention is to introduce Kali through the perspective of doing security
testing, the following subjects are covered:
Foundations of Kali Linux
Linux has a rich history, going back to the 1960s with Unix.
This chapter covers a
bit of the background of Unix so you can better understand why the tools in
Linux work the way they do and how best to make efficient use of them. We’ll
also look at the command line since we’ll be spending a lot of time there through
the rest of the book, as well as the desktops that are available so you can have a
comfortable working environment.
If you are new to Linux, this chapter will pre‐
pare you to be successful with the remainder of the book so you aren’t over‐
whelmed when we start digging deep into the tools available.
Network Security Testing Basics
The services you are most familiar with listen on the network. Also, systems that
are connected to the network may be vulnerable. To be in a better position to
perform
testing over the network, we’ll cover some basics of the way network
protocols work. When you really get deep into security testing, you will find an
understanding of the protocols you are working with to be an invaluable asset.
We will also take a look at tools that can be used for
stress testing of network
stacks and applications.
Reconnaissance
When you are doing security testing or penetration testing, a common practice is
to perform reconnaissance against your target. A lot of open sources are available
that you can use to gather information about your target. This will not only help
you with
later stages of your testing, but also provide a lot of details you can
share with the organization you are performing testing for. This can help them
correctly determine the footprint of systems available to the outside world. Infor‐
mation about an organization and the people in it can provide stepping stones
for
attackers, after all.
Looking for Vulnerabilities
Attacks against organizations arise from vulnerabilities. We’ll look at vulnerabil‐
ity scanners that can provide insight into the technical (as opposed to human)
vulnerabilities that exist at your target organization. This will lead to hints on
where to go from here, since the objective of security testing
is to provide insights
to the organization you are testing for about potential vulnerabilities and expo‐
sures. Identifying vulnerabilities will help you there.
Automated Exploits
While Metasploit may be the foundation of performing security testing or pene‐
tration testing, other tools are available as well. We’ll cover the basics of using
Advanced Techniques and Concepts. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 315

Programming Errors 324
Buffer Overflows 325
Heap Overflows 327
Return to libc 329
Writing Nmap Modules 330
Extending Metasploit 333
Disassembling and Reverse Engineering 336
Debugging 337
Disassembling 341
Tracing Programs 343
Other File Types 345
Maintaining Access and Cleanup 346
Metasploit and Cleanup 346
Maintaining Access 347
Summary 349
Useful Resources 349
11.
Reporting. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 351
Determining Threat Potential and Severity 352
Writing Reports 354
Audience 354
Executive Summary 355
Methodology 356
Findings 357
Taking Notes 358
Text Editors 358
GUI-Based Editors 360
Notes 361
Capturing Data 362
Organizing Your Data 364
Dradis Framework 365
CaseFile 368
Summary 370
Useful Resources 370
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
viii | Table of Contents
Preface
A novice was trying to fix a broken Lisp machine by turning the power off and on.
Knight, seeing what the student was doing, spoke sternly: “You cannot fix a machine
by just power-cycling it with no understanding of what is going wrong.”
Knight turned the machine off and on.
The machine worked.
—
AI Koan
One of the places over the last half century
that had a deep hacker culture, in the
sense of learning and creating, was the Massachusetts Institute of Technology (MIT)
and,
specifically, its Artificial Intelligence Lab. The hackers at MIT generated a lan‐
guage and culture that created words and a unique sense of humor. The preceding
quote is an AI koan, modeled on the koans of Zen, which
were intended to inspire
enlightenment. Similarly, this koan is one of my favorites because of what it says: it’s
important to know how things work.
Knight
, by the way,
refers to Tom Knight, a
highly respected programmer at the AI Lab at MIT.
The intention for this book is to teach readers about the capabilities of Kali Linux
through the lens of security testing. The idea is to help you better understand how
and why things work. Kali Linux is a security-oriented
Linux distribution, so it ends
up being popular with people who do security testing or penetration testing for either
sport or vocation. While it does have its uses as a general-purpose
Linux distribution
and for use with forensics and other related tasks, it really was designed with security
testing in mind. As such, most of the book’s content focuses
on using tools that Kali
provides. Many of these tools are not necessarily easily available with other Linux dis‐
tributions. While the tools can be installed, sometimes built from source,
installation
is easier if the package is in the distribution’s repository.
Cross-Site Request Forgery

Cross-Site Request Forgery A
cross-site request forgery (CSRF) attack creates a request that appears to be associ‐
ated with one site when, in fact, it’s going to another site. Or, put another way, a user
Web-Based Attacks | 251
visits one page that either is on site X or appears to be on site X when in fact a request
on that page is being requested against site Y. To understand this attack, it helps to
know how HTTP works and how websites work. In order to understand this, let’s
take a look at some simple HTML source in
Example 8-3
.
Example 8-3. Sample HTML source code This is a title
Table of Contents - Learning Kali Linux

Denial-of-Service Tools 51
Encryption Testing 55
Packet Captures 60
Using tcpdump 61
Berkeley Packet Filters 63
Wireshark 65
Poisoning Attacks 68
ARP Spoofing 69
DNS Spoofing 72
Summary 73
Useful Resources 74
3.
Reconnaissance. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
What Is Reconnaissance? 75
Open Source Intelligence 77
Google Hacking 79
Automating Information Grabbing 81
Recon-NG 85
Maltego 88
DNS Reconnaissance and whois 92
DNS Reconnaissance 92
Regional Internet Registries 96
Passive Reconnaissance 99
Port Scanning 101
TCP Scanning 102
UDP Scanning 102
Port Scanning with Nmap 103
High-Speed Scanning 106
Service Scanning 109
Manual Interaction 110
Summary 112
Useful Resources 113
Auto CAD grafik dasturi tarixi

Auto CAD grafik dasturi tarixi.
AutoCad – chizmani komputerda tahrirlash dasturi Amerikaning Autodesk firmasi tomonidan ishlab chiqilgan bo’lib, dastlabki versialari o’tgan asrning 80 yillarida chiqarilgan va keng ommalashib ketgan.
Tizimning doimiy rivojlanib borishi, foydalanuvchilarning e’tiroz va maslaxatlari inobatga olinib, kamchiliklarni muayan bartaraf etish va boshqa firmalar maxsulotlari (ayniqsa Microsoft) bilan integrasialashuvi ushbu dasturni butun dunyoda keng ommalashuviga olib keldi.
Ushbu dasturning Rossiada keng tarqalishi uning 10 – versiasidan boshlandi. U MS DOS operasion tizimi tarkibida ishlar edi. Keyinchalik, 12 – 13 versialarga doir shu tizimda ishladi va ular sekinlik bilan “WINDOWS” (WINDOWS 3.1 yoki WINDOWS – 95) operasion tizimiga o’tkazila bordi. 14 – versia to’liq WINDOWS operasion tizimiga o’tkazildi.
1999 yilda AutoCAD ning 15 – versiasi chiqdi va u foydalanuvchilar orasida AutoCAD – 2000 nomini oldi. AutoCAD ning 16 – versiasi (AutoCAD - 2004) 2004 yilning Mart oyida chiqdi va endilikda firma ularning WINDOWS – 95, 98 operasion tizimlarida yaxshi ishlashiga kafolat bermasdi. Sababi ushbu dasturning to’liq imkoniyatlaridan foydalanish uchun yanada mukammalroq operasion tizimlar kerak edi.{5}
Hozirgi kunga kelib, AutoCAD – 2007 dasturi foydalanuvchilar orasida keng ommalashgan bo’lib:
|
«Simvоl» - Belgi - Pedagogika fakulteti

|
Pedagogika fakulteti
|
bet | 14/54 | Sana | 24.03.2021 | Hajmi | 5,98 Mb. | | #13476 |
«Simvоl» - Belgi faol tugmasi. U orqali ko’plab belgilanishlarni kiritish mumkin. Masalan: diametr, radius, burchak, kvadrat, kub, delta va h…
Harflarning og’ish burchagini belgilab beradi.
Harflar orasidagi masofalarni belgilab beradi.
Harflarni kengligini belgilab beradi.
«Оdnоstrоchniy» - Bir qatorli matn kiritish.
Ushbu funcsiya bir qatorli so’zlarni, son va raqamlarni, belgilanishlarni kiritish uchun qo’llaniladi. Bu jarayon uch bosqichdan iborat. Birinchi bosqichda matn kiritiladigan joy sichqoncha orqali tanlanadi. Ikkinchi bosqichda harf balandligi klaviatura orqali kiritiladi. Uchinchi bosqichda esa qatorning og’ish burchagi sichqoncha yoki klaviatura orqali kiritiladi.
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Mavzuning dоlzarbligi - Pedagogika fakulteti

Mavzuning dоlzarbligi: Ijоdkоr shaхsning muhim qоbiliyatlaridan biri uning fazоviy tasavvur qila оlishidir. Fazоviy tasavvur insоn intеlеktining tarkibiy qismlaridan biri bo`lib, uning yuqоri darajada shakllanganligi bo`lajak mutaхasis qanday faоliyat turi bilan shug’ullanmasin, albatta muvaffaqiyatli bajarilishini ta’minlaydi. Jumladan kоnstruktоr, dizaynеr, arхitеktоr, amaliy san’at ustalari kabi ko`plab sоha vakillarining kasbiy vazifilarini bajarishda fazоviy tasavvurning yuqоri darajada shakllanganligi muhim ahamiyatga ega.
Bоzоr iqtisоdiyoti sharоitida har qanday ishga ijоdiy yondashadigan, nоstandart еchimlar tоpa оladigan injеnеr, lоyihachi, dizaynеr va umummuhandislik mutaхasislarni tayyorlash grafik fanlarning, хususan Kоmpyutеr grafikasi fanining rоli juda kattadir.
Hozirgi kunda respublikamizning barcha oliy o’quv yurtlari, kasb- hunar kollejlari va umumta`lim o`rta maktablarida Auto CAD grafik dasturidan foydalanish juda og’ir kechmoqda.
Buning bir nеchta sababini ko`rsatib o`tamiz.
—Maktab chizmachilik dasturida kоmpyutеr grafikasi uchun ajralilgan sоatlar miqdоri nihоyatda оz;
—Dasturda ko`rsatilgan chizish dasturlaridan fоydalanuvchi sifatida ishlab bilish uchun vaqt еtarli emas;
—Chizmachilik o`qituvchilari “AutoCAD”, “3D MAX”, “Kоmpas”, “CorelDRAW” va “Photoshop” dasturlari bilan to`liq tanish emas;
Manashularning oldini olishning qisqacha bo’lsa ham algoritmi ko’rsatilgan
Shunday qilib, muhandislik grafikasi fanlari darslarida talabalarga qog’ozdan ko’ra kompyuterda ishlash qulayroqdir.
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DRV8825 va A4988 - Step motor nima va u qanday ishlaydi?

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Step motor nima va u qanday ishlaydi?
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bet | 11/13 | Sana | 09.02.2024 | Hajmi | 12,35 Mb. | | #153839 |
Bog'liq stepper word DRV8825 va A4988
Xo'sh, endi men boshida aytib o'tgan DRV8825 drayveridan foydalanib, qadam motorlarini qanday boshqarishimiz mumkinligini ko'rib chiqaylik.
Aslida, A4988 step drayveri bilan step motorlarini boshqarish haqida biz hozirgacha tushuntirgan hamma narsa DRV8825 uchun ham amal qiladi. Ish printsipi, ulanishlar va kodlash ikkala drayver uchun deyarli bir xil. Ularning orasidagi farq ularning texnik xususiyatlarida va endi biz ularni ko'rib chiqamiz va ularni taqqoslaymiz.
DRV8825 Texas Instruments tomonidan ishlab chiqarilgan step drayveri bo'lib, u Allegro A4988 drayverini to'g'ridan-to'g'ri almashtirish sifatida ishlatilishi mumkin, chunki ularning ulanishlari bir xil. Ularning orasidagi uchta asosiy farq shundaki, DR8825 qo'shimcha sovutishsiz (1,5A va 1A) A4988 ga qaraganda ko'proq tokni etkazib bera oladi, u yuqori maksimal kuchlanish kuchlanishiga ega (45V va 35V) va u yuqori mikrostep aniqligini (32 va 16 mikrostep) taqdim etadi. ).
Albatta, ularning boshqa kichik farqlari ham bor. Misol uchun, joriy chegara potansiyometri boshqa joyga ega va oqim chegarasi sozlamalari va mos yozuvlar pinining kuchlanishi o'rtasidagi munosabatlar boshqacha. DRV8825 mantiqiy quvvat manbaiga muhtoj emas va bu pin joylashuvi FAULT chiqishi sifatida ishlatiladi.
Biroq, FAULT pinini to'g'ridan-to'g'ri 5V ga ulash xavfsizdir, shuning uchun DRV8825 A4988 drayveri uchun mo'ljallangan tizimlarda to'g'ridan-to'g'ri almashtirish sifatida ishlatilishi mumkin.
Shuni ta'kidlash kerakki, A4988 drayverini DRV8825 bilan almashtirishda haydovchining yo'nalishi to'g'ri ekanligiga ishonch hosil qilish juda muhimdir. Men allaqachon aytib o'tganman, ularning potansiyometrlari turli joylarda, A4988da u chip ostida, DRV8825da esa chipning ustida joylashgan va bu ba'zida chalkashlikka olib kelishi mumkin va drayverni noto'g'ri tomonga osongina joylashtirish mumkin.
Oqim chegarasini o'rnatish uchun biz mos yozuvlar kuchlanishini GND dagi bitta prob bilan, ikkinchisini esa potansiyometrning o'zida o'lchashimiz mumkin.
DRV8825 step drayverini hisoblash formulasi quyidagicha:
Joriy chegara = Vref x 2
Microstepping rezolyutsiyasini tanlashga kelsak, biz quyidagi jadvaldan foydalanishimiz mumkin.
Umuman olganda, DRV8825 A4988-ga qaraganda yaxshiroq step haydovchi hisoblanadi, chunki u yuqori oqim va kuchlanish ko'rsatkichlari va yuqori mikrostep o'lchamlarini taklif qiladi, bu esa step motorining silliq va jim ishlashiga olib keladi.
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TMC2208 step haydovchi - Step motor nima va u qanday ishlaydi?

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Step motor nima va u qanday ishlaydi?
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bet | 12/13 | Sana | 09.02.2024 | Hajmi | 12,35 Mb. | | #153839 |
Bog'liq stepper word TMC2208 step haydovchi
Yumshoqroq va jimroq ishlash haqida gapirganda, keling, TMC2208 step drayverini ko'rib chiqaylik. TMC2208 chipi harakatni boshqarish elektronikasiga ixtisoslashgan Germaniyada joylashgan Trinamic kompaniyasi tomonidan ishlab chiqarilgan. TMC2208 tovushsiz qadamli motor drayveri bo'lib, uni A4988 yoki DRV8825 drayverlari uchun mo'ljallangan tizimlarda to'g'ridan-to'g'ri almashtirish sifatida ham ishlatish mumkin. U ish stoli 3D printerlarida, lazer gravürlarida, skanerlarda va hokazolarda keng qo'llaniladi.
Ushbu drayverni boshqa ikkitasidan ajratib turadigan narsa uning 256 ta bo'linma yoki mikropog'onani ta'minlovchi integratsiyalashgan interpolyatsiya birligidir. Bu chip ichida ichki ishlab chiqarilgan mukammal sinusoidal boshqaruvga imkon beradi. Bu shuni anglatadiki, biz ikkita MS pinlari, 2, 4, 8 yoki 16 mikrosteplar orqali qanday mikrostep ruxsatini tanlagan bo'lishimizdan qat'iy nazar, haydovchi step motoriga 256 mikroqadam chiqaradi. Bu yumshoqroq ishlashni ta'minlaydi va mikrokontrollerning yukini sezilarli darajada kamaytiradi.
Haydovchining bu xususiyati shovqinsiz tokni boshqarish StealthChop2 texnologiyasi bilan birgalikda step motorlarining ultra jim boshqaruvini ta'minlaydi. Bu erda uchta haydovchi o'rtasidagi shovqin darajasini taqqoslash.
Step haydovchi shovqin darajalari: A4988 65dB atrofida, DRV8825 67dB atrofida va TMC2208 41dB atrofida.
TMC2208 step motorlarini butunlay jimgina boshqaradi, bu juda ta'sirli.
TMC2208 ning joriy reytingi A4988 drayveridan biroz yuqoriroq yoki u 2A maksimal oqim bilan 1,2A ni tashkil qiladi. Drayvning joriy chegarasini o'rnatish uchun yana boshqa drayverlar uchun tushuntirilgan usuldan foydalanishimiz mumkin. Biz mos yozuvlar kuchlanishini GND ustidagi bitta prob bilan, ikkinchisi esa "Enable" pinining yonidagi to'liq o'ng tomonda o'lchashimiz kerak.
Joriy chegarani hisoblash formulasi quyidagicha:
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