In theory an fm signal contains an infinite number of side frequencies so that the band. Although it may not be quite as straightforward as amplitude modulation, nevertheless frequency modulation, fm, offers some distinct advantages. Modulation is defined as the process by which some characteristics of a carrier signal is varied in accordance with a modulating signal. The theory of frequency modulation and demodulation. Assuming that m 0 for the msample delay no delay, plot the coef. It is also possible to change the frequency of a signal to give frequency modulation or fm. In telecommunications and signal processing, frequency modulation fm is the encoding of. In analog applications, the carrier frequency is varied in direct proportion to changes in the amplitude of an input signal. Introduction to modulation and demodulation free download as powerpoint presentation. Frequency modulation is a form of modulation, which represents information as variations in the instantaneous frequency of a carrier wave. Introduction to modulation and demodulation modulation.
Angle modulation is the process in which the frequency or the phase of the carrier varies according to the message signal. What is fm, frequency modulation electronics notes. In the diagram, the modulation frequency, km, is 500. Build simple fm demodulator by using frequency discriminator. In amplitude modulation the amplitude of high frequency sine wave carrier is varied in accordance with the instantaneous value of the modulating. To study and perform pulse width modulation and demodulation.
Frequency modulation fm is the standard technique for highfidelity. Pdf practical approach to frequency modulation and. Frequency modulation definition, basics and waveform hd. If a high pass filter is used, the demodulation process is much more linear since the. Frequency modulation is the process of varying the frequency of the carrier signal linearly with the message signal. Laboratory manual principles of communication system lab ee226f ivth semester. This principle is at the heart of amplitude modulation. Frequency modulation is that from of angle modulation in which the.
The typical frequency of the transmitted and received signal is. A modem is an equipment that performs both modulation and demodulation. In frequency modulation, the amplitude of the carrier. To study and perform frequency modulation and demodulation. Frequency modulation fm is a process in which the carrier frequency is varied by the amplitude of the modulating signal i.
The demodulation of a fm signal requires a circuit that yields an output voltage. Build simple envelope detector for fm demodulation. The goal of this experiment is to become familiar with fm modulation and demodulation. This is further divided into frequency and phase modulation. Fequency modulation and demodulation theory are practice or proof using emona datex training tools. Scribd is the worlds largest social reading and publishing site. Analog iq modulationtransceiver iq signals take on a continuous range of values as viewed in the time domain used for amfm radios, television nonhdtv, and the first cell phones newer systems typically employ digital modulation instead receiver output 2cos2.
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