请使用MATLAB绘制4PAM调制解调在信噪比从0到14的高斯信道下传输的理论误码率和误比特率

好的，下面是MATLAB代码实现：

clear all;
close all;
clc;

M = 4; % Modulation order
k = log2(M); % Number of bits per symbol
EbNoVec = 0:14; % Eb/No values to simulate
numSymPerFrame = 10000; % Number of symbols per frame
numFrames = 5; % Number of frames to simulate
totNumBits = numFrames*numSymPerFrame*k; % Total number of bits transmitted

% Generate a vector of random bits
dataIn = randi([0 1], totNumBits, 1);

% Create a 4PAM modulator System object
pamMod = comm.PAMModulator(M);

% Create a 4PAM demodulator System object
pamDemod = comm.PAMDemodulator(M);

% Create an AWGN channel System object
awgnChannel = comm.AWGNChannel('NoiseMethod', 'Signal to noise ratio (Eb/No)', 'EbNo', EbNoVec(1));

% Create a bit error rate calculator System object
berCalc = comm.ErrorRate;

% Loop over the various Eb/No values
for n = 1:length(EbNoVec)
    % Set the channel Eb/No
    awgnChannel.EbNo = EbNoVec(n);
    
    % Initialize the error statistics
    numErrs = 0;
    numBits = 0;
    
    % Loop over the number of frames to simulate
    for p = 1:numFrames
        % Generate a vector of random bits
        dataIn = randi([0 1], totNumBits, 1);
        
        % Modulate the data
        dataMod = step(pamMod, dataIn);
        
        % Pass the modulated data through the channel
        dataRx = step(awgnChannel, dataMod);
        
        % Demodulate the received data
        dataDemod = step(pamDemod, dataRx);
        
        % Calculate and accumulate the number of bit errors
        bitErrs = sum(dataIn ~= dataDemod);
        numErrs = numErrs + bitErrs;
        
        % Accumulate the total number of bits
        numBits = numBits + totNumBits;
    end
    
    % Calculate the bit error rate and add it to the BER vector
    berVec(n) = step(berCalc, numErrs, numBits);
end

% Calculate the theoretical bit error rate and add it to the BER vector
EbNo = EbNoVec(1:15);
berTheory = 0.5*erfc(sqrt(0.5*10.^(EbNo/10)));

% Plot the theoretical and simulated bit error rates
semilogy(EbNoVec, berVec, 'o-', 'LineWidth', 2);
hold on;
semilogy(EbNo, berTheory, 'r-', 'LineWidth', 2);
grid on;
legend('Simulation', 'Theory');
xlabel('Eb/No (dB)');
ylabel('Bit Error Rate');

执行代码后，将会绘制出理论误码率和误比特率随信噪比的变化曲线图。