Electrons Dancing with Photons in the Ocean of Digits http www wired com gadgetlab 2009 06 gallery deepinside the iphone 3g s Peek inside of a cell phone Lot s of chips Integrated Circuits What s inside of these chips Copyright Prof Ali M Niknejad Cell Phone by EE Courses Copyright Prof Ali M Niknejad Hybrid Technology Prius Copyright Prof Ali M Niknejad Solar Cells Copyright Prof Ali M Niknejad Cyber Physical Systems CPS Orchestrating networked computational resources with physical systems Building Systems Transportation Avionics Air traffic control at SFO Telecommunications Automotive Instrumentation E Corner Siemens Factory Power generation automation and distribution Daimler Chrysler Military systems Courtesy of Kuka Robotics Corp Soleil Synchrotron EE Trichotomy Devices Circuits You can touch and feel devices Semiconductors are materials of choice properties can be engineered Information is ultimately represented by electrons and holes and or photons Any interconnection of devices that performs a useful function Digital circuits analog circuits RF and microwave Systems The theory behind EE systems A model for the system that includes noise non linearity feedback and dynamics Most often digital signal processing algorithms used Copyright Prof Ali M Niknejad Some EE History Copyright Prof Ali M Niknejad Telegraphy First there was telegraphy use Vail Morse code to send messages over long distances Patented in the US in 1837 by Morse and Vail West coast connected by 1861 end of Poly Express Telegraph cables run along train tracks moving both information people and goods rapidly along the country Copyright Prof Ali M Niknejad Transatlantic Cable Transatlantic cable completed by 1866 worked only a few days before it failed Led to the advancement in the theory of transmission lines Copyright Prof Ali M Niknejad Bell Alexander Graham Bell was the first to be awarded a patent for the electric telephone by the United States Patent and Trademark Office USPTO in March 1876 10 March 1876 The first successful telephone transmission of clear speech using a liquid transmitter when Bell spoke into his device Mr Watson come here I want to see you and Watson heard each word distinctly Copyright Prof Ali M Niknejad Tesla The induction motor another Tesla invention In 1891 Nikola Tesla demonstrate wireless transmission of signals and he suggested wireless telegraphy as an application Copyright Prof Ali M Niknejad Bose In November 1894 the Bengali Indian physicist Jagadish Chandra Bose demonstrated publicly the use of radio waves in Calcutta did not file for a patent Copyright Prof Ali M Niknejad Wireless Radio Started as wireless telegraphy The history of the invention of the radio is very disputed Marconi widely recognized as an early inventor although he played a more important role in commercializing the radio In 1895 he sent signals 1 5 km Transatlantic in 1902 Copyright Prof Ali M Niknejad Titanic Boost in Radio In 1912 the RMS Titanic sank in the northern Atlantic Ocean Wireless radio transmissions telegraph were used to report the ship s location Britain s postmaster general summed up referring to the Titanic disaster Those who have been saved have been saved through one man Mr Marconi and his marvellous invention Copyright Prof Ali M Niknejad Early Ultra Wideband Radio In the beginning these sparks generated ultrawideband interference which represented Vail code The systems were essentially passive vacuum tubes and transistors were not yet invented and just realized with LC tanks and transformers Copyright Prof Ali M Niknejad First Audio Transmissions Reginald Fessenden Invented amplitude modulated AM radio so that more than one station can send signals as opposed to sparkgap radio where one transmitter covers the entire bandwidth of the spectrum On Christmas Eve 1906 Reginald Fessenden made the first radio audio broadcast from Brant Rock MA Ships at sea heard a broadcast that included Fessenden playing O Holy Night on the violin and reading a passage from the Bible Copyright Prof Ali M Niknejad AM FM Wireless Radio The dominant telegraph company of the time was Western Union They had a monopoly on telegraphy and they dismissed telephony and radio Telegraph gave way to audio transmission mainly phone lines and broadcast radio Frequency modulation FM was invented by Armstrong in 1935 FM has greater noise immunity than AM but requires more bandwidth Copyright Prof Ali M Niknejad Digital Communications By sampling a signal and quantizing it turning it into finite precision numbers we can easily store it using digital technology and we can also transmit it digitally Audio signals for example need to be sampled at about 20 000 times per second and with a resolution of around 18 bits to completely retain the fidelity of the signal for the human ear Today information is still transmitted with AM and FM but the amplitude and phase of the signal are mapped into a finite alphabet These digital signals are more noise immune and can be coded guarded to prevent correct and detect errors in transmission Copyright Prof Ali M Niknejad Devices Copyright Prof Ali M Niknejad Devices Devices Physical stuff you can touch and feel Manufacturing driven largely by integrated circuit IC fabrication The building block of ICs Transistors Transistors used to make Logic gates memory amplifiers Devices include electronic devices and optical devices Electron and hole transport through metals and semiconductors Semiconductors can be engineered to have specific properties conductivity The junction between two semiconducting materials is where the magic happens Photons light used to carry information through waveguides fiber optics or through electromagnetic radiation radios wireless Semiconductor junctions can generate photos or detect photons optical receivers solar cells Copyright Prof Ali M Niknejad The Transistor Invented at Bell Laboratories on December 16 1947 by William Shockley seated at Brattain s laboratory bench John Bardeen left and Walter Brattain right Inventors awarded Nobel Prize Probably the most important even in EE history Copyright Prof Ali M Niknejad Bell labs was the research lab of a telephone company As such the importance of the transistor was not recognized by many of the business folks at AT T Device was flaky and low power compared to vacuum tubes the workhorse device of the time for signal amplification In 1952 first transistorized radios appear Compared to vacuum tube transistors were
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