(Guided - hardwire) (Unguided, wireless, softwire) :

,

:

( ) ()

(multi - point)

(Twisted Pair)

(Coaxial cable)

(Optical fiber)

40 km5 s/km0.2 0.5dB/km186 370THz

1 9 km4 s/km7 dB/km -10MHz0 500MHz

2 km5 s/km0.7 dB/km -1kHz0 1 MHz()

2 km50 s/km0.2 dB/km -1 kHz0 3.5 kHz

.

(local exchange) - (subscriber loop)

PBX (Private Branch

Exchange) (LAN Local Area Network)

10Mb/s, 100Mb/s 1Gb/s, 10 Gb/s

5km 6km

a 2km 3km

: , (1MHz) (100MHz)

. . . .

- UTP (Unshielded Twisted Pair) () j aje .

STP(Shielded Twisted Pair)

() ( , )

3 (Cat 3) 16MHz () 7.5 cm 10 cm

4 (Cat 4) 20 MHz

5 (Cat 5) 100MHz 0.6 cm 0.85 cm

UTP

UTP 5 (Cat 5E) 5

100MHz 6 (Cat 6)

200MHz 7 (Cat 7)

600MHz

Oe - e e

31.3--21.4-300

38.532-12.322.0-100

47.541-6.210.4-25

50.444234.48.213.616

5853322.24.15.64

5862411.12.02.61

150-STP

. 5 UTP

. 3 UTP

150-STP

. 5 UTP

. 3 UTP

.(MHz)

(dB) (dB 100 m)

2.21.51.210.7

(Cat 5 =1)

SSTPUTP/FTPUTP/FTPUTP/FTPUTP

600 MHz200 MHz100 MHz100 MHz16 MHz

.7 F

. 6 E. 5E

. 3 D

. 3 C

10000

()

km 500MHz

1km

-

Gbps

10-

-

(Long-haul) (trunks)

-

1014 1015 Hz

LED(Light Emitting Diode)

ILD (Injection Laser Diode)

()

.(THz)

820 900nm 366 333 Multimode LAN

1280 1350nm

234 222 S Single mode

1528 1561nm

196 192 C Single mode

WDM

1561 1620nm

185 192 L Single mode

WDM

2GHz 40GHz -

30MHz 1GHz () Broadcast

3 x 1011 2 x 1014

MIR= Mid infrared HF= High freq. HX= Hard X-Rays FIR= Far infrared MF= Medium freq. SX= Soft X-Rays

LF= Low freq. EUV= Extreme ultraviolet EHF= Extremely high freq. VLF= Very low freq. NUV= Near ultraviolet SHF= Super high freq. VF/ULF= Voice freq.

UHF= Ultra high freq. SLF= Super low freq. NIR= Near Infrared VHF= Very high freq. ELF= Extremely low freq.

380450 nm 450495 nm 495570 nm 570590 nm 590620 nm 620750 nm

()

( ...) :

( ) e

() (pattern)

() () .

() ()

.

(dB)

(Line of sight) .

:

, .

35,784km

-

Broadcast

(Omnidirectional) FM UHF VHF (multipath interference)

Broadcast

TV , IRD

:

2MHz AM

...

30Mhz

~3 x 108 m/s ,

,

Sin()/sin( )

( )

22GHz, 15GHz 60GHz, 30GHz

(Multipath) e

!