Communication System and AM modulation convert to Coherent demodulation

This is the code for AM Modulation. Can you write Matlab code also for AM coherent demodulation. Do not use ammode and amdemod command. You can use diff, filter and integral command in matlab code. Please give answer.

%% AM Modulation

A=0.5; %carrier amplitude;

fc= 10*10^3; %carrier frequency 10 KHz

CarrierSignal= cos(2*pi*fc*t);

ModulatedSignal = [A + signal].*CarrierSignal;

subplot(2,2,3)

plot(t,ModulatedSignal); %plot the absolute spectrum

xlabel('Time')

ylabel('Amplitude')

title('AM Modulated Signal in Time')

% Find the spectrum Modulated Signal by taking FFT

ModulatedSignalFFT=fft(ModulatedSignal,nfft);

ShifFFT = fftshift(ModulatedSignalFFT);

ABSModulatedSignalFFT=abs(ShifFFT)/N0;

freqm = (-nfft/2:nfft/2-1)/(nfft*Ts);

subplot(2,2,4)

%PlotSpectrum of the Modulated Signal

plot(freqm,ABSModulatedSignalFFT); %plot the absolute spectrum

xlabel('Frequency (Hz)')

ylabel('Amplitude')

title('Two-Sided Spectrum of AM Modulated Signal')

Answer 1

[Sai Sri Pathuri]

You may refer this answer or follow the below steps for basic DSBSC/SSBSC coherent demodulator. Let the received signal be receivedSignal

% output of Product Modulator
v = receivedSignal*CarrierSignal;
% Pass throught a low pass filter to get the demodulated signal
demodSignal = Hpf(v); % Hpf is the low pass filter. You may create it using Filter designer or builder