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Physical Layer
Computer Networks
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Where are we?
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Numbering Systems
Binary Hexadecimal Decimal
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Transmission of Information
From Physics Energy Electromagnetic wave propogation
From Mathematics Coding Theory
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Analog and Digital Signaling
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Amplitude Modulation
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Frequency Modulation
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Baseband and Broadband
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Phase Modulation
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Modems
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Digital Encoding
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CSU/DSU
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Undesirable Effects and Limitations
Propagation Delay Bandwidth Noise Interference Distortion Attenuation
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Sampling and Nyquists Theorem
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Shannons Limit
Corrects for SNR
Encoding more bits per cycle time helps, but you cannot overcome the fundamental physical limits of a real transmission system.
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Timing
Asynchronous bit level
Synchronous character level
Isochronous timing coordination must be successful
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Transmission Media
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Connectors
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Media Test and Measurement
Hands-on Demo
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Repeaters
Signal Regeneration Clean up Amplifly Distance Extension
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Hubs
Repeater functionality, plus... Concentration Point Signal Distribution Device Management Functions
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Throughput versus Bandwidth
Usable capacity Determined by
engineering
Electrical Property Determined by
physics