Amplitude Modulator

[Damian Marek]

Attached is an amplitude modulator programmed in Matlab. The component accepts an optical signal and modulates its signal according to another electrical signal.

The optical signal can be any number of sampled signals centered at different central frequencies as well as including noise bins and parameterized signals. Depending on which type of input signal is present, the associated Matlab function will be called (AmplitudeModulatorNoise.m for noise).

[Damian Marek]

Matlab code follows:

Main Component File:

global ModulationIndex

OutputPort1 = InputPort1; % create an output structure

ModulationIndex = Parameter0;

SampledNumber = length(InputPort1.Sampled);
ParameterizedNumber = length(InputPort1.Parameterized);
NoiseNumber = length(InputPort1.Noise);

if( SampledNumber > 0 ) % if there is sampled signal do

for i=1:SampledNumber

OutputPort1.Sampled(i).Signal(1,:) = AmplitudeModulatorSampled(InputPort1.Sampled(i).Signal(1,:), real(InputPort2.Sampled.Signal))

PolarizationNumber = size(InputPort1.Sampled(i).Signal,1);

if( PolarizationNumber == 2)

OutputPort1.Sampled(i).Signal(2,:) = AmplitudeModulatorSampled(InputPort1.Sampled(i).Signal(2,:), real(InputPort2.Sampled.Signal));

end;
end
end;

if( ParameterizedNumber > 0 ) %if there is parameterized signal do

for i=1:ParameterizedNumber

OutputPort1.Parameterized.Power = AmplitudeModulatorParameterized(InputPort1.Parameterized.Power, real(InputPort2.Sampled.Signal));

end
end;

if( NoiseNumber > 0 ) %if there noise signal do

for i=1:NoiseNumber

OutputPort1.Noise.Power = AmplitudeModulatorNoise(InputPort1.Noise.Power, real(InputPort2.Sampled.Signal));

end
end;

Modulate for Noise Bins:

function y = AmplitudeModulatorNoise( Noise, dModulation )

global ModulationIndex

nSize = length(dModulation);

dSum = 0;

dSum = dSum + sum( (1 – ModulationIndex) + ModulationIndex * dModulation );

dSum = dSum / nSize;

y = Noise * dSum;

Modulate for Parameterized Signals:

function y = AmplitudeModulatorParameterized(Parameterized, dModulation);

global ModulationIndex

nSize = length(dModulation);

dSum = 0;

dSum = sum( (1 – ModulationIndex) + ModulationIndex * dModulation );

dSum = dSum / nSize;

y = Parameterized * dSum;

Modulate for sampled signals:

function y = AmplitudeModulatorSampled(pccE, dModulation);

global ModulationIndex

nSize = length(pccE);
dModL = length(dModulation);

resize = ones(1, nSize/dModL);
resize = kron(dModulation, resize);
resize(nSize+1:end) = [];

for i = 1:nSize,
pccE(i) = pccE(i) * sqrt( (1 – ModulationIndex) + ModulationIndex * resize( i ) );
end;

y = pccE;

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