# How do you do amplitude modulation in Matlab?

## How do you do amplitude modulation in Matlab?

Create a time vector 100 seconds long.

1. fs = 100; t = (0:1/fs:100)’; Set the carrier frequency to 10 Hz.
2. fc = 10; x = sin(2*pi*t); Modulate x using single- and double-sideband AM.
3. ydouble = ammod(x,fc,fs); ysingle = ssbmod(x,fc,fs);
4. sa = dsp.SpectrumAnalyzer(‘SampleRate’,fs, ‘
5. step(sa,ysingle)

How do you calculate amplitude modulation?

The equation for the overall modulated signal is obtained by multiplying the carrier and the modulating signal together. The constant A is required as it represents the amplitude of the waveform. Note also that the sidebands are separated from the carrier by a frequency equal to that of the tone.

What is modulation index formula?

The FM modulation index is equal to the ratio of the frequency deviation to the modulating frequency. To give an example of the FM modulation index, take the example where a signal has a deviation of ±5kHz, and the modulating frequency is 1kHz, then the modulation index for this particular instance is 5 / 1 = 5.

### How do you demodulate an AM signal in Matlab?

Demodulate AM Signal

1. Copy Command.
2. fc = 10e3; fs = 80e3; t = (0:1/fs:0.01)’;
3. s = sin(2*pi*300*t)+2*sin(2*pi*600*t);
4. [num,den] = butter(10,fc*2/fs);
5. y = ammod(s,fc,fs);
6. z = amdemod(y,fc,fs,0,0,num,den);
7. plot(t,s,’c’,t,z,’b–‘) legend(‘Original Signal’,’Demodulated Signal’) xlabel(‘Time (s)’) ylabel(‘Amplitude’)

How do you create a carrier signal in Matlab?

Examples

1. Copy Command. Set the sampling frequency to 1kHz and carrier frequency to 200 Hz.
2. fs = 1000; fc = 200; t = (0:1/fs:0.2)’;
3. x = sin(2*pi*30*t)+2*sin(2*pi*60*t);
4. fDev = 50;
5. y = fmmod(x,fc,fs,fDev);
6. plot(t,x,’c’,t,y,’b–‘) xlabel(‘Time (s)’) ylabel(‘Amplitude’) legend(‘Original Signal’,’Modulated Signal’)

How is Vmin calculated?

Each voltage is then rectified and summed up in series as in following examples:

1. for 2phases (180deg apart) => series sum yields pulsing voltage with Vmin(2) = 0 volt minimums and Vmax(2) = 2 volt maximums.
2. 3p (120d) => Vmin(3) = sqrt(3) and Vmax(3) = 2.
3. 4p (90d) => Vmin(4) = 2 and Vmax(4) = 2*sqrt(2)

#### What are the types of amplitude modulation?

Types of Amplitude Modulation They are; Double sideband-suppressed carrier modulation (DSB-SC). Single Sideband Modulation (SSB). Vestigial Sideband Modulation (VSB).

Which statement is correct for modulation index in amplitude modulation?

In amplitude modulation the amplitude of the high frequency carrier wave is made to vary in proportion to the amplitude of the audio signal. This is the correct option.

What is modulation index value?

Modulation index describes the extent to which modulation is done on a carrier signal. The value of the modulation index is kept less than 1 to avoid distortions in the modulated signal because it is very hard to demodulate the signal.