Incl

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‫‪ I‬ﺗﻀﻤﻴﻦ ﺍﻟﻮﺳﻊ‪:‬‬ ‫‪ (1‬ﻣﻔﻬﻮ ﻡ ﺍﻟﺘﻀﻤﻴﻦ‪:‬‬ ‫(‬ ‫ﺇﺭﺴﺎل ﺭﺴﺎﻝﺔ ﺇﻝﻰ ﺍﺸﺨﺹ ﻤﻌﻴﻥ‪ ،‬ﻴﺴﺘﻭﺠﺏ ﺘﺤﻭﻴل ﺍﻷﻓﻜﺎﺭ ﺍﻝﻤﺭﺍﺩ ﺇﺭﺴﺎﻝﻬﺎ ﺇﻝﻰ ﻨﺹ‪ ،‬ﻭﻜﺘﺎﺒﺔ ﻫﺫﺍ ﺍﻝﻨﺹ ﻓﻲ ﺭﺴﺎﻝﺔ ‪ ،‬ﺜﻡ ﻭﻀﻊ ﺍﻝﺭﺴﺎﻝﺔ‬ ‫ﻓﻲ ﻅﺭﻑ‪ ،‬ﻭﺇﺭﺴﺎل ﺍﻝﻅﺭﻑ ﻋﺒﺭ ﺍﻝﺒﺭﻴﺩ ﺇﻝﻰ ﺍﻝﻭﺠﻬﺔ ﺍﻝﻤﺨﺼﺼﺔ ﻝﻬﺎ‪ ،‬ﻓﺎﻝﺘﻀﻤﻴﻥ ﺍﻝﺫﻱ ﺘﻡ ﻫﻨﺎ ﻫﻭ ﺘﺠﻬﻴﺯ ﺍﻝﻤﻌﻠﻭﻤﺎﺕ ﺒﺼﻭﺭﺓ ﺘﻜﻭﻥ‬ ‫ﻤﻨﺎﺴﺒﺔ ﻹﺭﺴﺎﻝﻬﺎ‪ ،‬ﻋﺒﺭ ﻭﺴﻴﻠﺔ ﺍﻹﺭﺴﺎل ﺍﻝﻤﻨﺎﺴﺒﺔ‪ ،‬ﻭﺍﻝﺫﻱ ﺴﺎﻋﺩ ﻓﻲ ﺫﻝﻙ ﻫﻭ ﻭﺠﻭﺩ ﻭﺴﻴﻠﺔ ﺤﺎﻤﻠﺔ ﻝﻬﺎ ‪ ،‬ﺃﻱ ﺇﻥ ﺘﺠﻬﻴﺯ ﺍﻝﻤﻌﻠﻭﻤﺔ ﻭﻓﻕ‬ ‫ﻤﻌﺎﻴﻴﺭ ﻤﻌﻴﻨﺔ‪ ،‬ﻭ ﺇﺭﺴﺎﻝﻬﺎ ﻋﺒﺭ ﻭﺴﻴﻠﺔ ﹸﺘﻌ ّ‪‬ﺩل ﺨﺼﺎﺌﺼﻬﺎ ﺤﺴﺏ ﺍﻝﻐﺎﻴﺔ ‪ ،‬ﺘﺴﻤﻰ ﻫﺫﻩ ﺍﻝﻌﻤﻠﻴﺔ ﺒﺎﻝﺘﻀﻤﻴﻥ‪.‬‬

‫ﺍﻟﻮﺳﻊ‪:‬‬ ‫‪ (2‬ﺗﻀﻤﻴﻦ ﺍﻟﻮﺳﻊ‬ ‫ﺍﻝﺘﻀﻤﻴﻥ ﻫﻭ ﺘﻌﺩﻴل ﺇﺸﺎﺭﺓ ﺍﻝﻤﻌﻠﻭﻤﺎﺕ ﻝﺒﻌﺽ ﺨﺼﺎﺌﺹ ﻤﻭﺠﺔ ﺤﺎﻤﻠﺔ ﺫﺍﺕ ﺘﺭﺩﺩ ﻋﺎل‪.‬‬ ‫ﻭﻴﻌﺘﺒﺭ ﺘﻀﻤﻴﻥ ﺍﻝﻭﺴﻊ ﺘﻘﻨﻴﺔ ﺘﻌﺘﻤﺩ ﻋﻠﻰ ﻀﺭﺏ ﺍﻹﺸﺎﺭﺓ ﺍﻝﺘﻲ ﺘﺤﻤل ﺍﻝﻤﻌﻠﻭﻤﺔ ﻓﻲ ﺇﺸﺎﺭﺓ ﺃﺨﺭﻯ  ا دد ﺘﺴﻤﻰ ﺒﺎﻹﺸﺎﺭﺓ ﺍﻝﺤﺎﻤﻠﺔ‪،‬‬ ‫) ﻭﻴﺘﻡ ﺫﻝﻙ ﺒﻌﺩ ﺇﻀﺎﻓﺔ ﺘﻭﺘﺭ ﺜﺎﺒﺕ ﻝﻺﺸﺎﺭﺓ ﺍﻝﺘﻲ ﺘﺤﻤل ﺍﻝﻤﻌﻠﻭﻤﺔ ﻤﻥ ﺃﺠل ﺇﺯﺍﻝﺔ ﺍﻝﺘﺸﻭﻴﺵ(‪.‬‬

‫ﺍﻟﺬﻱ ﻳﻀﻢ ﺍﻟﻤﻌﻠﻮﻣﺔ‪:‬‬ ‫ﺩﺩ ﺍﻟﺘﻮﺗﺮ ﺍﻟﺬﻱ‬ ‫ﺗﻌﺒﻴﺮ ﻭﺗﺮﺩﺩ‬ ‫‪ (3‬ﺗﻌﺒﻴﺮ‬ ‫(‬ ‫ﻴﻤﻜﻥ ﺃﻥ ﻴﻜﻭﻥ ﺍﻝﺘﻭﺘﺭ ﺍﻝﺫﻱ ﻴﻀﻡ ﺍﻝﻤﻌﻠﻭﻤﺔ ﺠﻴﺒﻴﺎ ﻭ ﺩﻭﺭﻴﺎ ﻨﺒﻀﻪ ‪.ωm=2πfm :‬‬ ‫‪. u m (t ) = U m cos ω m .t‬‬ ‫‪ : m‬ﺘﻌﻨﻲ‪ Modulant‬ﺃﻱ‪ :‬ﺍﻝﻤﻀ ‪‬ﻤـّﻥ‪.‬‬ ‫ﻨﻀﻴﻑ ﺇﻝﻴﻪ ﺍﻝﺘﻭﺘﺭ ﺍﻝﺜﺎﺒﺕ ‪ UO‬ﻓﻴﺼﺒﺢ ﺍﻝﻤﺠﻤﻭﻉ‪:‬‬ ‫‪u1 (t)= um (t) +UO‬‬

‫ا ا‪s= 500 µs/div :‬‬

‫اور  ب‪ <= 4,5div :‬ا دد‬

‫‪f m ≈ 444 Hz‬‬

‫‪ (4‬ﺗﻌﺒﻴﺮ ﻭﺗﺮﺩﺩ ﺍﻟﺘﻮﺗﺮ ﺍﻟﺤﺎﻣﻞ‪:‬‬ ‫(‬ ‫ﺍﻝﻤﻭﺠﺔ ﺍﻝﺤﺎﻤﻠﺔ ﺫﺍﺕ ﺘﺭﺩﺩ ﻋﺎل ﻭﻫﻲ ‪:‬‬ ‫‪ u p (t ) = U p . cos ω p .t‬ﺘﻭﺘﺭ ﺍﻝﻤﻭﺠﺔ ﺍﻝﺤﺎﻤﻠﺔ‪.‬‬ ‫‪ : p‬ﺘﻌﻨﻲ‪ Porteuse‬ﺃﻱ‪ :‬ﺍﻝﺤﺎﻤﻠﺔ‪.‬‬

‫ﺍﻝﻜﺴﺢ ﺍﻷﻓﻘﻲ ﺍﻝﻤﺴﺘﻌﻤل ﻫﻭ ‪ 10 −5 s / div :‬ﻭﻤﻨﻪ ﺘﺭﺩﺩ ﺍﻝﻤﻭﺠﺔ ﺍﻝﺤﺎﻤﻠﺔ ‪ f P = 18.10 4 Hz = 180kHz .‬ﻭﻫﻭ ﺘﺭﺭﺩ ﺠﺩ ﻋﺎل‪.‬‬

‫ﺍﻝﺤﺴﺎﺴﻴﺔ ﺍﻝﺭﺃﺴﻴﺔ ‪ <=2V/div‬ﻭﺴﻊ ﺍﻝﻤﻭﺠﺔ ﺍﻝﺤﺎﻤﻠﺔ ‪. U p = 4V :‬‬ ‫‪1‬‬

‫(ﺇﻧﺠﺎﺯ ﻋﻤﻠﻴﺔ ﺍﻟﺘﻀﻤﻴﻦ‪:‬‬ ‫‪( 5‬ﺇﻧﺠﺎﺯ‬ ‫ﻭﺘﻘﻨﻴﺎ‪ ،‬ﺘﺘﻡ ﻋﻤﻠﻴﺔ ﺍﻝﺘﻀﻤﻴﻥ ﺒﻭﺍﺴﻁﺔ ﺘﺭﻜﻴﺏ ﺇﻝﻜﺘﺭﻭﻨﻲ ﺨﺎﺹ ‪:‬ﺩﺍﺭﺓ ﻤﺘﻜﺎﻤﻠﺔ ﻤﻨﺠﺯﺓ ﻝﻠﺠﺩﺍﺀ ‪.‬‬

‫ﻋﻨﺩ ﻤﺨﺭﺝ ﺍﻝﺩﺍﺭﺓ ﺍﻝﻤﺘﻜﺎﻤﻠﺔ ﺍﻝﻤﻨﺠﺯﺓ ﻝﻠﺠﺩﺍﺀ ﻨﺤﺼل ﻋﻠﻰ ﺩﺍﻝﺔ ‪ u s (t ) :‬ﺘﺘﻨﺎﺴﺏ ﺇﻀﻁﺭﺍﺩﺍ ﻤﻊ ﺍﻝﺠﺩﺍﺀ ) ‪u1 (t ).u 2 (t‬‬ ‫‪: k ،‬ﺜﺎﺒﺘﺔ ﺍﻝﺘﻨﺎﺴﺏ ﻭﻫﻲ ﺘﺘﻌﻠﻕ ﺒﺎﻝﺩﺍﺭﺓ ﺍﻝﻤﺘﻜﺎﻤﻠﺔ ‪.‬‬ ‫)‪us(t) =k. u1(t) .u2(t‬‬ ‫ﻤﻊ ‪:‬‬ ‫ﻭﻤﻨﻪ ‪:‬‬

‫‪u1 (t ) = u m (t ) + U O‬‬

‫) ‪u 2 (t ) = u p (t‬‬

‫ﻭ‪:‬‬

‫) ‪u s (t ) = k [u m (t ) + U O .].u p (t‬‬ ‫‪u s (t ) = k [U m cos ω m .t + U O .].U p . cos ω p .t‬‬

‫‪u (t ) = U m (t ). cos ω p .t‬‬ ‫=<‬

‫ﺒﻤﻘﺎﺭﻨﺔ‬

‫)‪ ( 1‬ﻭ )‪( 2‬‬

‫ﻨﻀﻊ ‪A = k .U p .U o :‬‬

‫)‪( 2‬‬

‫ﻭﺴﻊ ﺍﻝﺘﻭﺘﺭ ﺍﻝﻤﻀﻤ‪‬ﻥ ﻫﻭ ‪:‬‬

‫ﻭ‪:‬‬

‫‪Um‬‬ ‫‪Uo‬‬

‫=‪m‬‬

‫ﺒﺤﻴﺙ ‪ m ،‬ﻫﻲ ‪ :‬ﻨﺴﺒﺔ ﺍﻝﺘﻀﻤﻴﻥ‪.‬‬

‫‪ω m = 2π . f m‬‬

‫ﻭﻴﻌﺒﺭ ﻋﻥ ﻨﺴﺒﺔ ﺍﻝﺘﻀﻤﻴﻥ ﺒﺩﻻﻝﺔ ‪ Um.max‬ﻭ ‪Um.min :‬‬

‫)‪U M :‬‬

‫‪2‬‬

‫ه ‬

‫‪ Um.max‬و ‪U m :‬‬

‫ه ‬

‫‪(Um.min‬‬

‫‪U M = 3div.2V / div = 6V‬‬ ‫‪U m = 1div.2V / div = 2V‬‬ ‫‪1‬‬ ‫‪1‬‬ ‫= ‪fm‬‬ ‫=‬ ‫ﺘﺭﺩﺩ ﺍﻝﺘﻭﺘﺭ ﺍﻝﻤﻀﻤﻥ ‪≈ 444 Hz :‬‬ ‫‪−6‬‬ ‫‪4,5div.500.10 s / div 2,25.10 −3 s‬‬ ‫ﻣﻠﺤﻮﻇﺔ ‪:‬ﺸﺭﻭﻁ ﺍﻝﺤﺼﻭل ﻋﻠﻰ ﺘﻀﻤﻴﻥ ﺠﻴﺩ‪:‬‬ ‫‪U‬‬ ‫ ﺃﻥ ﺘﻜﻭﻥ ﻨﺴﺒﺔ ﺍﻝﺘﻀﻤﻴﻥ ‪ m = m < 1 :‬ﺃﻱ ‪:‬‬‫‪. Uo > Um‬‬ ‫‪Uo‬‬ ‫‪ -‬ﺃﻥ ﻴﻜﻭﻥ ﺘﺭﺩﺩ ﺍﻝﺘﻭﺘﺭ ﺍﻝﺤﺎﻤل ‪ f p‬ﺃﻜﺒﺭ ﺒﻜﺜﻴﺭ ﻤﻥ ﺘﺭﺩﺩ ﺍﻝﺘﻭﺘﺭ ﺍﻝﻤﺭﺍﺩ ﺘﻀﻤﻴﻨﻪ ‪ ) f m‬ﻋﻠﻰ ﺍﻷﻗل ‪.( f p > 10 f m‬‬

‫ﻓﻲ ﻫﺫﻩ ﺍﻝﺤﺎﻝﺔ ﻻ ﻨﺤﺼل ﻋﻠﻰ ﺸﺒﻪ ﺍﻝﻤﻨﺤﺭﻑ ﻋﻨﺩ ﺍﺴﺘﻌﻤﺎل ﺍﻝﺭﺯ ‪ XY‬ﻝﺭﺍﺴﻡ ﺍﻝﺘﺫﺒﺫﺏ ‪ ،‬ﺒل ﻨﺤﺼل ﻋﻠﻰ ﺍﻝﺸﻜل‬

‫‪ (I‬ﺇﺯﺍﻟﺔ ﺍﻟﺘﻀﻤﻴﻦ‪:‬‬ ‫(‬ ‫‪ (1‬ﻣﻔﻬﻮﻡ ﺇﺯﺍﻟﺔ ﺍﻟﺘﻀﻤﻴﻦ‪:‬‬ ‫(‬ ‫‪3‬‬

‫ﺍﻝﺘﺎﻝﻲ‪:‬‬

‫‪ (2‬ﺘﻌﺭﻴﻑ ﺍﻝﻤﺭﺸﺢ‪: Filtres:‬‬ ‫– ﺍﻝﻤﺭﺸﺢ ﺍﻝﻤﻤﺭﺭ ﻝﻠﺘﺭﺩﺩﺍﺕ ﺍﻝﻌﺎﻝﻴﺔ ‪ ،‬ﻴﺴﻤﺢ ﺒﻤﺭﻭﺭ ﺍﻹﺸﺎﺭﺍﺕ ﺫﺍﺕ ﺍﻝﺘﺭﺩﺩﺍﺕ ﺍﻝﻌﺎﻝﻴﺔ ‪ ،‬ﻭﻫﻭ ﻤﻜﻭﻥ ﻤﻥ ﺜﻨﺎﺌﻲ ﻗﻁﺏ ‪RC‬ﻋﻠﻰ ﺍﻝﺘﻭﺍﻝﻲ‪.‬‬

‫ﺍﻝﻤﺭﺸﺢ ﺍﻝﻤﻤﺭﺭ ﻝﻠﺘﺭﺩﺩﺍﺕ ﺍﻝﻤﻨﺨﻔﻀﺔ ‪ ،‬ﻴﺴﻤﺢ ﺒﻤﺭﻭﺭ ﺍﻹﺸﺎﺭﺍﺕ ﺫﺍﺕ ﺍﻝﺘﺭﺩﺩﺍﺕ ﺍﻝﻤﻨﺨﻔﻀﺔ ‪ ،‬ﻭﻫﺫﺍ ﺍﻝﻨﻭﻉ ﻫﻭ ﺍﻝﺫﻱ ﻋﻠﻰ ﺴﻨﺴﺘﻌﻤﻠﻪ‬‫ﻹﺯﺍﻝﺔ ﺍﻝﻤﻭﺠﺔ ﺍﻝﺤﺎﻤﻠﺔ‪ .‬ﻭﻫﻭ ﻤﻜﻭﻥ ﻤﻥ ﺜﻨﺎﺌﻲ ﻗﻁﺏ‪RC‬ﺍﻝﺘﻭﺍﺯﻱ‪.‬‬

‫ﺍﻝﺠﺯﺀ ﺍﻝﻤﺘﺒﻘﻰ ﻤﻥ ﺍﻝﺤﺎﻤﻠﺔ ‪ ،‬ﺘﺘﻡ ﺇﺯﺍﻝﺘﻪ ﺒﺎﺴﺘﻌﻤﺎل ﻜﺎﺸﻑ ﺍﻝﻐﻼﻑ‪.‬‬ ‫ﺒﺘﺠﻤﻴﻊ ﺼﻤﺎﻡ ﺜﻨﺎﺌﻲ ﻭﺜﻨﺎﺌﻲ ﻗﻁﺏ)‪ RC‬ﻋﻠﻰ ﺍﻝﺘﻭﺍﺯﻱ( ﻨﺤﺼل ﻋﻠﻰ ﻜﺎﺸﻑ ﺍﻝﻐﻼﻑ ﻭﻫﻭ ﺭﺒﺎﻋﻲ ﻗﻁﺏ‪.‬‬

‫ﺘﺒﻴﺎﻨﺔ ﺩﺍﺭﺓ ﻜﺎﺸﻑ ﺍﻝﻐﻼﻑ‬ ‫ﻤﻠﺤﻭﻅﺔ‪:‬ﻝﻠﺤﺼﻭل ﻋﻠﻰ ﻜﺸﻑ ﻏﻼﻑ ﺠﻴﺩ ﻴﻨﺒﻐﻲ ﺃﻥ ﺘﹸﺤﻘﻕ ﺜﺎﺒﺘﺔ ﺍﻝﺯﻤﻥ ﻝﺜﻨﺎﺌﻲ ﺍﻝﻘﻁﺏ ‪ RC :‬ﺍﻝﻤﺘﺭﺍﺠﺤﺔ ﺍﻝﺘﺎﻝﻴﺔ‪:‬‬ ‫‪ : T p‬دور ا‪ "*+‬ا)(" ‪ : Tm‬دور ا! رة ا' َـّ‪."#‬‬ ‫‪T p ≤ τ ≤ Tm‬‬ ‫‪ 09‬إزا" ا '‪>? @A7 -/‬ف ا آ;" ا  ة ( ‪ - ، U o :+‬أ* ذ‪ ( )  0 2 3‬ددات ا‪+7 8/)9 ، "/0‬م ا‪5‬‬ ‫‪D9 C 2‬زا" ا آ;" ا  ة ( ‪. :+‬‬

‫‪Sbiro abdelkrim‬‬ ‫‪Lycée agricole oulad –taima région d’Agadir Maroc‬‬ ‫‪Mail : [email protected]‬‬ ‫‪msn : [email protected]‬‬ ‫‪pour toute observation contactez moi‬‬

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