10 2020 档案
摘要：Vector Quantization In scalar quantization each output of the discrete-time source is quantized separatelyand then encoded. For example, if we are usi
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摘要：Quantization In the previous section we studied two methods for noiseless coding; that is, compressionof the source output sequence such that full rec
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摘要：Measure of Information Noiseless Coding Noiseless coding is the general term for all schemes that reduce the number of bits requiredfor the representa
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摘要：Analog-to-Digital Conversion The majority of information sources are analog by nature. Analog sources includespeech, image, and many telemetry sources
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摘要：Angle Modulation Angle-modulation schemes, which include frequency modulation (FM) and phase modulation(PM), belong to the class of nonlinear modulati
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摘要：Conventional AM Demodulation The conventional AM is inferior to DSB-AM and SSB-AM whenpower and SNR are considered. The reason is that a usually large
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摘要：Conventional AM Demodulation The conventional AM is inferior to DSB-AM and SSB-AM whenpower and SNR are considered. The reason is that a usually large
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摘要：Demodulation of AM Signals Demodulation is the process of extracting the message signal from the modulated signal.The demodulation process depends on
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摘要：Demodulation of AM Signals Demodulation is the process of extracting the message signal from the modulated signal.The demodulation process depends on
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摘要：SSB-AM SSB-AM is derived from DSB-AM by eliminating one of the sidebands. Therefore,it occupies half the bandwidth of DSB-AM. Depending on the sideban
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摘要：Amplitude Modulation (AM) Amplitude modulation (AM), which is frequently referred to as linear modulation, isthe family of modulation schemes in which
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摘要：Frequency-Hopped Spread Spectrum In frequency-hopped (FH) spread spectrum the available channel bandwidth W is subdividedinto a large number of nonove
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摘要：Generation of PN Sequences A PN sequence is a code sequence of l's and O's whose autocorrelation has properties similar to those of white noise. Refer
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摘要：Code Division Multiple Access The enhancement in performance obtained from a DS spread spectrum signal throughthe processing gain and the coding gain
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摘要：Direct-Sequence Spread Spectrum Systems Let us consider the transmission of a binary information sequence by means of binaryPSK. The information rate
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摘要：Spread Spectrum Communication Systems Spread spectrum signals for digital communications were originally developed andused for military communications
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CCS - Channel Capacity and Coding - Channel Coding - Decoding LDPC Codes - The Sum-Product Algorithm
摘要：The Sum-Product Algorithm The sum-product algorithm, which belongs to the class of message-passing algorithms,is an iterative decoding algorithm for L
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摘要：Decoding LDPC Codes - The Bit-Flipping Algorithm The bit-flipping algorithm is a hard-decision decoding algorithm with low complexity. A modified, and
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摘要：Low-Density Parity-Check Codes Low-density parity-check codes (LDPC) are linear block codes that are characterizedby a sparse parity-check matrix. The
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摘要：Iterative Decoding for Turbo Codes We have seen that optimal decoding of turbo codes is impossible due to the large numberof states in the code trelli
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摘要：Turbo Codes Shannon's random coding theorem states that codes achieving channel capacity musthave random, or close to random, distribution as well as
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摘要：Error Probability Bounds for Convolutional Codes Finding bounds on the error performance of convolutional codes is different from themethod used to fi
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摘要：Decoding of Convolutional Codes Viterbi Algorithm There exist many algorithms for decoding of convolutional codes. The Viterbi algorithmis probably th
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摘要：Representation of Convolutional Codes Trellis Diagram Reference, 1. <<Contemporary Communication System using MATLAB>> - John G. Proakis
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摘要：Convolutional Codes In block codes each sequence of k information bits is mapped into a sequence of nchannel inputs in a fixed way regardless of the p
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摘要：Performance of Linear Block Codes Linear block codes can be decoded using either soft-decision decoding or hard-decisiondecoding. In a hard-decision d
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摘要：Hamming Codes Matlab Coding 1 % MATLAB script for Illustrative Problem 10.9. 2 echo on 3 k=11; 4 for i=1:2^k 5 for j=k:-1:1 6 if rem(i-1,2^(-j+k+1))>=
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摘要：Linear Block Codes Linear block codes are the most important and widely used class of block codes. Ablock code is linear if any linear combination of
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