Ondes lectromagntiques et transmission dinformations :

Ondes lectromagntiques et transmission dinformations

1- 2- 3- 4- 5-

RLC ( : ) RC multiplieur

LC

1

2

: AM FM SW

AM FM SW

3

Modem

. : AM FM -

2381 : Morse 6781 : Bell 3781 :Maxwell 9881 :Hertz 0981 :Popov 5981 :Marconi 0391 2691 6491 0791 9691 1991 GSM

: LC

E B

f)Hz( 3.1020 3.1017 3.1014 3.108 3.105MF BF

3.1011

EHF SHF UHF THF HF

VISIBLE R RX UV IR

10-12

10-9

10-5

10-3

1

103

)m(

1-C=3.108ms T f ((=C.T

Transmission dinformation

-

: ( )

1- : Cbles coaxiaux Les fibres optiques 2- ()Latmosphre Le vide

()

Cot Maintenance Installation Protection Dbit

Paires torsade Cbles coaxiaux Fibres optiques

IR Laser tlcommande : ... ... D.IR PD.IR

IR Laser-

: 4991 2,4GHz-2,8GHz

-

IR Laser

:

fmin

fmax

: f = fmax fmin

20Hz f 20KHz 3.1014Hz f 7,5.1014Hz variable >1GHz >100MHz >100 KHz f

: , , : 102Hz 104Hz ( - - - ,...)

-

- ((= /2 L

-

:

Modem

-

Atmosphre

-

A fs s: )s)t( = SmCos)2fs t +s )p)t( = PmCos)2fpt+p :

(0291) AM

) p)t( =Pm)t(Cos)2fpt+p (9391) FM

) p)t( = PmCos)2fp)t(t+p

)p)t( = PmCos)2fpt+p))t

AM : : Amplitude Modulation 335KHz - 1700KHz FM : : Frequency Modulation 88MHz - 108MHz : : SW Short Waves 5,9MHz - 26,1MHz

680KHz

336: AD3 3 6AD

Multiplieur

336: AD

HF Sortie BF

: s)t( = SmCos)2f)t : p)t( = PmCos)2fp)t 0U : ()HF ()BF

0U

(p)t( = PmCos)2fpt

0s)t(=SmCos)2fst(+U

(Us)t(=Kx[s)t(+U0]xp)t

K

((Us)t( = Kx[s)t(+U0]x)PmCos)2fpt (= KPm[s)t(+U0]Cos)2fpt (= a[s)t(+b] Cos)2fpt (= Um)t( Cos)2fpt Us))t )s)t

)s)t

Umax

Umin

Umin = KPm)-Sm+U0(

Umax = KPm)Sm+U0(

Umax - Umin = 2KPmSm

=m

=

: :

0Sm fs : 1>m 1=m

( 0)Sm>U ( 0)Sm=U

1>m 0Sm>U

1=m 0Sm=U

1