在MATLAB中设计一个稍微复杂的ofdm系统

以下是一个稍微复杂的OFDM系统的MATLAB代码：

%% OFDM System Design
clear all; close all; clc;

%% Parameters
N = 64; % Number of subcarriers
cp_len = 16; % Length of cyclic prefix
EbNo = 10; % Signal to noise ratio
num_symbols = 100; % Number of symbols to transmit
M = 16; % Modulation order
bits_per_symbol = log2(M);

%% Generate data
data = randi([0 1], num_symbols * N * bits_per_symbol, 1);

%% Modulate data
mod_data = qammod(data, M);

%% Reshape data
mod_data = reshape(mod_data, N, num_symbols);

%% Add cyclic prefix
cp_data = [mod_data(N-cp_len+1:N,:); mod_data];

%% Perform IFFT
ifft_data = ifft(cp_data);

%% Add noise
Es = mean(abs(ifft_data(:)).^2);
Eb = Es / bits_per_symbol;
N0 = Eb / (10^(EbNo/10));
noise = sqrt(N0/2) * (randn(size(ifft_data)) + 1i*randn(size(ifft_data)));
noisy_ifft_data = ifft_data + noise;

%% Perform FFT
fft_data = fft(noisy_ifft_data);

%% Remove cyclic prefix
rx_data = fft_data(cp_len+1:end,:);

%% Demodulate data
rx_data = reshape(rx_data, num_symbols * N, 1);
demod_data = qamdemod(rx_data, M);

%% Calculate bit error rate
errors = sum(demod_data ~= data);
ber = errors / length(data);

disp(['Bit Error Rate: ', num2str(ber)]);

%% Plot transmitted and received signals
figure(1);
subplot(2,1,1);
plot(real(mod_data(:,1)));
hold on;
plot(imag(mod_data(:,1)));
title('Transmitted Signal');
xlabel('Subcarrier');
ylabel('Magnitude');
legend('Real','Imaginary');

subplot(2,1,2);
plot(real(rx_data(:,1)));
hold on;
plot(imag(rx_data(:,1)));
title('Received Signal');
xlabel('Subcarrier');
ylabel('Magnitude');
legend('Real','Imaginary');