A LIMIT ON MODULATION WHETHER THE "SIGNAL" IS DIGITAL OR ANALOG: THE FREQUENCY OF THE CARRIER MUST BE GREATER THAN THAT OF THE "SIGNAL". IF YOU THINK BACK TO THE "COLORED FLASHLIGHTS ON FIBER" EXAMPLE, YOU CAN IMAGINE THAT IF WE TURN THE FLASHLIGHT ON AND OFF BEFORE IT CAN GENERATE ONE WAVELENGTH, THE LIGHT MIGHT NOT HAVE THE COLOR WE EXPECT. THIS EXPLAINS WHY MODEM SPEEDS ARE LIMITED AND WHY FIBER IS SO WONDERFUL.

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This page is part of a section of lecture slides related to " Modulation " within the topic "Digital Transmission Technology". Other slides within this section and other sections of slides for the topic "Digital Transmission Technology" can be accessed using the links below. Baseband Transmission HISTORICAL DIGITAL COMMUNICATION TELEGRAPH SIGNALS BINARY SIGNALS SYNCHRONIZATION MANCHESTER ENCODING Transmission Media TRANSMISSION MEDIA ELECTRICAL MEDIA OPTICAL FIBER Multiplexing MULTIPLEXING TIME DIVISION MULTIPLEXING FREQUENCY DIVISION MULTIPLEXING WHAT IS LIGHT? PROPERTIES OF WAVEFORMS THE ELECTRO-MAGNETIC SPECTRUM Modulation MODULATION MODULATION AND CARRIERS THE WAVE LAB MODULATION ON OTHER MEDIA A LIMIT ON MODULATION ANALOG MODULATION Understanding Bandwidth REMEMBER WHAT "FDM" MEANS? WHY SINE WAVES? FOURIER SERIES BANDWIDTH