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A System's View of Communications From Signals to Packets, Using MATLAB and Wireshark

Link to Files from System's View of Communications From Signals to Packets, Part 1, Point to Point Links

Parts 1 and 2 of this course focused on the physical layer, where as Part 3 focused on the rest of the communication stack layers, link, network, transport and application.

Part 1 for Point to Point Links: Basic engineering tools used and tradeoffs encountered in the design of communication systems like mobile phones for a point-to-point link, which communicates information from a single transmitter to a single receiver.

Topics From Part 1 (physical layer):

• Error Correction Coding for sending a waveform (adding bits)


• Bits-to-waveforms (sent on channel)


• Encoding bits to send


• Continuous verses discrete waveforms representation


• Discrete time channel step response


• Communication protocols


• Inter-symbol interference


• Recursive channel model


• Performance evaluation


• Equalization


• Additive noise


• Bit error rate


• From a received waveform on channel, convert waveforms-to-bits


• Error Correction on Received Waveform


• bit errors


• parity bit code


• repetition code


• channel coding


• eye diagrams

Part 2 - examined how multiple transmitters can share the same physical channel using MATLAB.

Link to Files from System's View of Communications From Signals to Packets, Part 2, how multiple transmitters can share the same physical channel using MATLAB

Topics From Part 2 (physical layer):

• lossless and lossy source coding compression


• sequence of yes/no questions


• entropy of a bit and a discrete random variable (lossless compression)


• entropy and the average code length


• Huffman source code for a set of symbols (lossless compression)


• parameters that control the shape of continuous and discrete time sinusoids


• signals as sums of sinusoids


• reconstruct a signal given its Fourier coefficients


• MP3 encoding used to compress our music files (lossy compression)


• why frequency domain analysis of signals is needed


• lossy source coding:
  • perceptual
  
  
  • time/frequency analysis
  
  
  • masking, non-uniform quantization
  
  
• frequency response of linear time invariant system


• different types of filters from their frequency response (low-pass, band-pass, high-pass)


• predict the output of a filter given the Fourier coefficients of its input and its frequency response


• complex exponential (numbers, exponentials, aliasing, discrete Fourier transform)


• relationship between the discrete Fourier series and the discrete Fourier transform


• frequency division multiplexing (to share channel, move signals in and out of frequency ranges)


• modulation and demodulation shifts signals from one part of the frequency spectrum to another


• Analyze modulation and demodulation using sine waves and complex exponentials


• Signal Transmission - Modulation: Radio Spectrum, Modulation


• Modulation with Complex Exponentials and Demodulation


• mixing using cosines


• mixing using complex exponentials


• Filtering


• Non-ideal effects


• effect of frequency and phase mismatches between the transmitter and receiver


• how digital data can be transmitted wirelessly using binary phase shift keying (BPSK)


• understand how quadrature phase shift keying can be used to double the rate information sent over the same channel - better efficiency


• I/Q modulation


• Quadrature phase shift keying (QPSK)


• interpret eye and constellation diagrams for performance analysis of channel

Part 3 - discussed how information can be transmitted reliably from one station to another over a network that connects multiple stations using MATLAB and Wireshark for the application layer.

Link to Files from System's View of Communications From Signals to Packets, Part 3, how information can be transmitted reliably from one station to another over a network that connects multiple stations using MATLAB and Wireshark for the application layer

Topics From Part 3 (Link, Network, Transport and Application Layers):

• Link Layer Topics:
  • Understanding the difference between circuit switching and packet switching
  
  
  • The use of layering in organizing network functionality
  
  
  • Multiple access protocols
  
  
  • How the Aloha protocol operates
  
  
  • Analyzing the efficiency of the slotted variant of the Aloha protocol
• Network Layer Topics:
  • Descriptions of the different functions of the network layer:
    • Addressing
    
    
    • Encapsulation
    
    
    • Routing and forwarding
    
    
  • Identifying differences between the distance vector and link state algorithms for routing
  
  
  • Applying the distance vector algorithm to estimate forwarding tables at nodes in a network iteratively
  
  
  • Calculating the best path in a network from one node to every other node using Dijkstra’s algorithm
  
  
• Transport Layer Topics:
  • The transport layer's functions
  
  
  • Descriptions of UDP and the TCP, and identifying differences between them
  
  
  • Explanations of how the stop-and-wait protocol ensures in-order packet transfer
  
  
  • Derivations of the throughput of the stop-and-wait protocol
  
  
  • Analyzing the increase in throughput enabled by the sliding window protocol.
  
  
• Application Layer Topics:
  • Understanding the internet hourglass
  
  
  • Descriptions of different application architectures, such as client-server and peer to peer
  
  
  • Illustrations of how the hypertext transfer protocol (HTTP) is used to retrieve information on webpages
  
  
  • Explanations of how the domain name system maps host names to IP addresses