Single sideband (SSB) modulation might be a sort of modulation used to send data, which includes an audio signal. Amplitude modulation produces an output signal in which the bandwidth is two times the most frequency of the original baseband signal. SSB modulation neglects this bandwidth increase, and also the power wasted on a carrier, at the price of more device complexity and tougher tuning at the receiver side.
The Expression for Single Side Band with Upper Side Band :
here,
m is the cosine wave with time duration of ‘t’,
fc is the carrier frequency,
t is the time duration and
mh s the Hilbert transform of baseband.
Example:
% MATLAB code for modulation % carrier frequency fc = 200; % baseband frequency fm = 30; % sampling frequency fs= 4000; % time duration t = (0 : 1 / fs :1 ); t = linspace(0, 1, 1000); % cosine wave with time duration of 't' m = cos(2 * pi * fm * t); % Hilbert transform of baseband mh = imag(hilbert(m)); % Single Side Band with Upper Side Band sb = m .* cos(2 * pi * fc * t) - mh .* sin(2 * pi * fc * t); %Demodulation by Synchronous method em = sb.*m; %Filtering High Frequemcies [ n,w ] = buttord(2/1000,4/1000, .5, 5); [ a,b ] = butter(n,w, 'low' );
dem = filter(a,b,em); % displaying the modulation figure; plot(t, sb); title( 'Single SideBand Modulation' );
xlabel( 'Time(sec)' );
ylabel( 'Amplitude' );
% displaying the demodulation figure; plot(t, em); title( 'Single SideBand Demodulation' );
xlabel( 'Time(sec)' );
ylabel( 'Amplitude' );
% displaying the filtered signal figure; plot(t, dem); title( 'Filtered Signal' );
xlabel( 'Time(sec)' );
ylabel( 'Amplitude' );
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Output: