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Wi-Fi
Internet senza fili cambia il mondo
delle
Telecomunicazioni
Breve panoramica dalle
ORIGINI al FUTURO
(fare click per procedere)
La telefonia ebbe origine da un illustre Italiano
… riconosciuto tardivamente …
But it seems that history must be
rewritten if justice is to be done to
an immigrant from Florence, Italy:
Antonio Meucci, who invented the
telephone in 1849 and filed his first
patent caveat (notice of intention to
take out a patent) in 1871, setting
into motion a series of mysterious
events and injustices which would
be incredible were they not so well
documented.
http://www.italianhistorical.org/MeucciStory.htm
Inventore del telefono
1808 - 1889
Le tappe dell’evoluzione
Brief History
1.
Telegraph invented by Gauss and Weber in 1834, perfected by Morse in 1844, Marconi
and Popov worked on wireless, and in 1901 trans Atlantic wireless from Cornwall to
Newfoundland.
2.
1860 Telephone developed by Reiss, 1876 Bell Telephone founded, 1878 first telephone
exchange in New Haven, CT, 1915 transcontinental telephone TJ Watson to AG Bell,
1953 transatlantic telephone cable, 1960s mobile radio (cellular).
3.
1900s AM invented and popularized by De Forest; commercial radio station begins
broadcasting in Pittsburgh 1920.
4.
1933 FM and angle modulation proposed by Armstrong (much opposition by De Forest),
but success by 1949.
5.
1929 Zworykin develops TV camera (iconoscope); 1939 BBC broadcasts TV, color TV in
US in 1954.
(da: http://www.media.mit.edu)
La telefonia : commutazione manuale
… Intanto Marconi inventava la radio
Guglielmo Marconi , (Bologna 1874 - Roma 1937)
è stato l' inventore italiano del primo sistema pratico di segnalazione radio. Studiò
a Bologna e a Firenze e fin da giovanissimo, intuendo la possibilità di utilizzare le
onde elettromagnetiche per inviare segnali a distanza, si interessò di telegrafia
senza fili. Verso il 1895, potete consultare anche 100 YEARS OF RADIO - HOME
PAGE , dopo numerosi esperimenti realizzati nella villa paterna di Pontecchio, mise
a punto un'apparecchiatura con cui riuscì a inviare segnali intelligibili a una
distanza di circa 2400 m, usando un'antenna direzionale. Dopo aver brevettato il
sistema telegrafico in Gran Bretagna (1896), fondò a Londra la Marconi's Wireless
Telegraph and Signal Company, nella quale lavorarono diversi scienziati a un
ulteriore perfezionamento dei progetti.
http://www.geocities.com/CapeCanaveral/Hall/2875/GAMT/marconi.htm
Marconi a bordo dell’ Elettra
… col campionamento la voce diventa digitale
Claude Elwood Shannon
1916 - 2001
Nyquist-Shannon
sampling theorem
From Wikipedia, the free encyclopedia.
The Nyquist-Shannon sampling theorem is the fundamental theorem in the field of
information theory, in particular telecommunications. It is also known as the
Whittaker-Nyquist-Kotelnikov-Shannon sampling theorem or just simply the
sampling theorem.
The theorem states that:
when sampling a signal (e.g., converting from an analog signal to digital), the
sampling frequency must be greater than twice the bandwidth of the input signal
in order to be able to reconstruct the original perfectly from the sampled version.
(Nyquist - 1928 ; Kotelnikov – 1933; Whittaker – 1935; Gabor – 1946; Shannon – 1948)
Dalle valvole …. ai transistor e Chips integrati
… verso l’alta densità di integrazione
Dal rame … alla fibra
Radio dal cielo …..
GALILEO: Un nuovo impiego estensivo dei satelliti
User Centric ICT Vision
WPAN / BAN
Transport
Short
Range
Optical
Solutions
EPON
GiBE
Wired
Access
IrDA
Sensors
IEEE 802.15x
RFID
WLAN
HiperLAN2
IEEE 802.11x
Proprietary
solutions
PLC
xDSL
LAN
ADSL
ADSL2
VDSL
Ethernet
IEEE 1394
HDSL
SDSL
Broadcasting
DVB-T
DAB
Other
Wireless
Access
Satellite
S-UMTS
Bluetooth
DVB-S
Broadband
Satellite
IEEE 802.16e
Cellular
Mobile
IEEE 802.20
UMTS
CDMA2000
PDC
GPRS
GSM
CDMAOne
EDGE
DECT
HomePlug
HomePNA
Narrow/
Broadband
Wireless
Access
Home
Plug and Play
EIB
Powerline
Quasi Cellular
MBS 60
MBS 40
Fixed BWA
HIPERACCESS
MVDS
LMDS
IEEE 802.16-2004
WiMAX applications
targeting 802.16d/e applications
IP Services for
SMALL BUSINESS
BACKHAUL for
HOTSPOTS
802.16REVd
RESIDENTIAL & SoHo
Wireless DSL
E1/T1 Leased-Lines
ENTERPRISE
802.16e
Full
Nomadism
WiFi
Veicoli del Futuro: Piattaforma di Telecomunicazioni
Universal telecom platform inside the car for communication
between the car (voice, data) and the outside
Security services: emergency, police
GSM
GPRS
UMTS
Web
Positionning
Public network
Voice and data from
conductor or passenger
Automotive diagnostic center
Automotive customer center
Navigation with traffic and Point of interest
Other applications
Technical Information from the car
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