Can a low pass signal be modulated?
Carry out the modulation, for example by multiplying the sine and cosine waveform with the I and Q signals, resulting in the equivalent low pass signal being frequency shifted to the modulated passband signal or RF signal.
Why low pass filter is used in demodulation process?
The capacitor and resistor form a low-pass filter to filter out the carrier frequency. Such a device is often used to demodulate AM radio signals because the envelope of the modulated signal is equivalent to the baseband signal.
How does FM demodulation work?
FM demodulation is a key process in the reception of a frequency modulated signal. Once the signal has been received, filtered and amplified, it is necessary to recover the original modulation from the carrier. It is this process that is called demodulation or detection.
What are the different demodulation techniques of FM?
There are different types of FM demodulators including: Slope Detector. Foster-Seeley Discriminator. Ratio Detector.
How do you do AM demodulation in Matlab?
Description. z = amdemod( y , Fc , Fs ) returns a demodulated signal z , given the input amplitude modulated (AM) signal y , where the carrier signal has frequency Fc . The carrier signal and y have sampling frequency Fs .
What is a low pass signal?
A low-pass filter (LPF) is a circuit that only passes signals below its cutoff frequency while attenuating all signals above it. It is the complement of a high-pass filter, which only passes signals above its cutoff frequency and attenuates all signals below it.
What is the difference between modulating signal and modulated signal?
Here as we can see that message signal also known as modulating signal is fed to the modulator. At the same time, a high-frequency carrier signal is also applied to the modulator whose characteristics are to be varied. Resultantly, a modulated signal is achieved at the output of the modulator.
Which device did we use for AM demodulation?
diode detector
A demodulator is a device that performs demodulation, which is the opposite process of modulation. The most basic equipment used for AM demodulation is a diode detector. A diode detector is made up of a diode and a few other parts.
What should be done to modulate a low-pass signal?
Baseband and Band-Pass Communication Systems Thus, the signal spectrum must be shifted to a higher frequency by modulating a carrier by the baseband signal. This can be done by amplitude and by angle modulation (frequency and phase).
Which demodulation technique is used in DTH?
Since the satellite link is a wireless microwave link and the base band signal is digital and the carrier is in form of sine wave one can use a digital modulation technique such as FSK, PSK, and QAM.