16-QAM with MATLAB Functions Introduction This section builds an example step-by-step to give you a first look at the Communications System Toolbox™ software. This section also shows how Communications System Toolbox functionalities build upon the computational and visualization tools in the underlying MATLAB ® environment. Modulate a Random Signal This example shows how to process a binary data stream using a communication system that consists of a baseband modulator, channel, and demodulator. The system's bit error rate (BER) is computed and the transmitted and received signals are displayed in a constellation diagram. The following table summarizes the basic operations used, along with relevant Communications System Toolbox and MATLAB functions. The example uses baseband 16-QAM (quadrature amplitude modulation) as the modulation scheme and AWGN (additive white Gaussian noise) as the channel model. Task Function Generate a Random Binary Data Stream randi Convert the Binary Signal to an Integer-Valued Signal bi2de Modulate using 16-QAM qammod Add White Gaussian Noise awgn Create a Constellation Diagram scatterplot Demodulate using 16-QAM qamdemod Convert the Integer-Valued Signal to a Binary Signal de2bi Compute the System BER biterr Generate a Random Binary Data Stream The conventional format for representing a signal in MATLAB is a vector or matrix. An object-oriented Matlab implementation of LTE Turbo codes is also discussed in detail. 1.4.1 Convolutional Codes. Ect the de- velopments in mobile. In telecommunication, a convolutional code is a type of error-correcting code that generates parity symbols via the sliding application of a boolean polynomial function to a data stream. This example uses the randi function to create a column vector that contains the values of a binary data stream. The length of the binary data stream (that is, the number of rows in the column vector) is arbitrarily set to 30,000. The code below also creates a stem plot of a portion of the data stream, showing the binary values. Duracell quick charger cef12n instructions for 941 tax. Notice the use of the colon (:) operator in MATLAB to select a portion of the vector. Define parameters. DataMod = qammod(dataSymbolsIn,M, 'bin');% Binary coding, phase offset = 0 dataModG = qammod(dataSymbolsIn,M);% Gray coding, phase offset = 0 The results are complex column vectors whose values are elements of the 16-QAM signal constellation. A later step in this example will plot the constellation diagram. To learn more about modulation functions, see. Also, note that the qammod function does not apply pulse shaping. To extend this example to use pulse shaping, see. For an example that uses Gray coding with PSK modulation, see. Add White Gaussian Noise The ratio of bit energy to noise power spectral density, E b/N 0, is arbitrarily set to 10 dB. From that value, the signal-to-noise ratio (SNR) can be determined. Given the SNR, the modulated signal, dataMod, is passed through the channel by using the awgn function. DataSymbolsOut = qamdemod(receivedSignal,M, 'bin'); dataSymbolsOutG = qamdemod(receivedSignalG,M); Convert the Integer-Valued Signal to a Binary Signal The de2bi function is used to convert the data symbols from the QAM demodulator, dataSymbolsOut, into a binary matrix, dataOutMatrix with dimensions of N sym-by-N bits/sym, where N sym is the total number of QAM symbols and N bits/sym is the number of bits per symbol, four in this case. The matrix is then converted into a column vector whose length is equal to the number of input bits, 30,000. The process is repeated for the Gray coded data symbols, dataSymbolsOutG. Anime megaman nt warrior sub indoxxi net. Reverse the bit-to-symbol mapping performed earlier. The Gray coding bit error rate = 1.33e-03, based on 40 errors Observe that Gray coding significantly reduces the bit error rate. Plot Signal Constellations The example in the previous section,, created a scatter plot from the modulated signal. Although the plot showed the points in the QAM constellation, the plot did not indicate which integers of the modulator are mapped to a given constellation point. This section illustrates two possible mappings: 1) binary coding, and 2) Gray coding. It was previously demonstrated that Gray coding provides superior bit error rate performance. Binary Symbol Mapping for 16-QAM Constellation Apply 16-QAM modulation to all possible input values using the default symbol mapping, binary. Elena Kong Mei Yee is a Hong Kong actress. (ATV) in 1997, she landed her first lead role in television drama 'Forest Cat'. Forrest Cat II TV Drama Series. Country: Hong Kong Language: Cantonese Release Date: 1999 Episodes: 32 Runtime: 45 minutes per episode Genre: Drama. Best hong kong cat 3.
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