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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