The purpose of this lab is for you to gain familiarity with the concepts of amplitude modulation and. The ase from the optical amplifier serves as the seed to be amplified, i. Applied sciences free fulltext a parallelphase demodulation. You are advised to read ahead, before attempting the experiment, to consider the modelling of this demodulator. T he classic definition of fm is that the instantaneous output frequency of a transmitter is varied in accordance with the modulating signal. Amplitude modulation process was published by on 20150406. In this video, frequency modulation and demodulation experiment is fully explained and described and is done in fm trainer kit scientech st 2203 kit where. Recent studies have shown that direct nerve stimulation can be used to provide sensory feedback to hand amputees.
The manuals are specially written to guide students through handson experiments and help them grasp the fundamental concepts of telecommunications. Using the signal generator and signal tracer to troubleshoot. Frequency modulation is a form of modulation, which represents information as variations in the instantaneous frequency of a carrier wave. Distinguish between different types of fm signal 4. The chopper modulation technique is widespread and essential to mitigate 1f noise and other low frequency noise, such as popcorn noise, voltage offsets, and drifts. Influence of mode competition and external wave frequency modulation on gyrotron. The ett101 laboratory manuals volumes 1 and 2 provide a turnkey solution for the teacher and student alike. Experiment with varying the modulating signal frequency and amplitude. Invented in 1933 by american engineer edwin armstrong, wideband fm is used worldwide to provide high fidelity sound over broadcast radio. Phase modulation, and frequency modulation are both the modulation techniques analyzed in angle modulation.
Comparison of linear frequency and amplitude modulation for. Designing frequency modulator and demodulator using simulink theory phase modulation pm and frequency modulation fm are special cases of anglemodulated signaling. We therefore assume mta mcos2 f mtfor pm and mta msim2 f mtfor fm. Download citation add to favorites reprints and permissions. Pdf frequency modulator romwald lihakanga academia. Please download the analog communications lab manual pdf ac lab manual. Cme312 lab manual dsbsc modulation and demodulation experiment 6 experiment 2 part iv. Using amplitude modulation to shift the baseband signal fm radio 88mhz108 mhz. Feel free to use the lab to practice your skills before the experiment.
Lab 5 amplitude modulation and demodulation was published by on 20150405. To study and perform frequency modulation and demodulation. Lab manual frequency modulation experiment 8 experiment 2 objectives. The experiment of rf modulation at the hls hefei light source is introduced. Tdm pulse amplitude modulationdemodulation trainer st2102. Active cancellation of residual amplitude modulation in a frequency. Experiment 10 frequency modulation 80382206 youtube.
Experiments experiment 1 34 to understand, synchronization and control signals available on st2102 experiment 2 36 to demonstrate the switching delay and its control on st2102 with potentiometer. Design the circuit for a carrier frequency of 30 khz. Pdf psychoacoustic equivalence of frequency modulation. A free powerpoint ppt presentation displayed as a flash slide show on id. Slide 6 narrow band fm slide 7 bandwidth of an fm signal slide 8 demod. Fm broadcasting is a method of radio broadcasting using frequency modulation fm. Frequency modulation and frequency demodulation experiment. A parallelphase demodulationbased distance measuremen. Since the amplitude is kept constant, fm modulation is a low noise process and provides a high quality modulation technique which is used for music and speech in hifidelity broadcasts. In analog applications, the carrier frequency is varied in direct proportion to changes in the amplitude of an input signal. Fsk frequency shift keying d1 61 conceptually, and in fact, the transmitter could consist of two oscillators on frequencies f1 and f2, with only one being connected to the output at any one time. Study of frequency modulation and demodulation using simulink matlab abstract. Carrier phase ft modulates ct in either amplitude, frequency or phase.
Communication is the transfer of information from one place to another. Pdh technique is essentially an application of frequency modulation fm spectroscopy,2. In this second experiment, we will examine the most common modulation scheme in daily life, namely, the frequency modulation, or fm. Theory lesson 36, principles of frequency modulation. The result of this operation is the simplified ii ptn b1. Slide 3 discretetime fm modulator slide 4 single tone fm modulation slide 5 single tone fm cont.
Lab 5 amplitude modulation and demodulation free html5 flip. Repeat step 5 by varying frequency of the modulating signal. Please see the fundamentals of analog communications section as discussed in the first experiment as a. To develop understanding of frequency modulation and demodulation using simulink. Influence of mode competition and external wave frequency. Experiment 2 experiment 6 experiment dsb sc modulation and. It is still in use today in a variety of systems, including, of course, am broadcast radio.
Download lab 5 amplitude modulation and demodulation pdf for free. Modulation is a process of translating information signal from low band frequency to high band frequency that is suits the. By the end of this experiment, the student should be able to. The virtual experiment environment propagated on this site emulates a realworld lab. Thus an fm transmitter is said to have a modulation sensitivity,represented by a constant, kf, of so many khzv, kf frequency deviationv kf khzv. Delaytimecalculator dtc is a simple software designed to help you calculate frequency modulation values in hertz and delay times in milliseconds for a song tempo in beats per minute or for a frequency value. Therefore we only consider the case where the message signal mtis a sinusoidal signal. In frequency modulation, the amplitude of the carrier wave is kept constant but its frequency is varied in accordance with the amplitude of the audio frequency signal. Examine the factors affecting the shape of the spectrum and the bandwidth of fm signals. We use modulation technique to alter signals in time and frequency to accomplish desired objectives. In effect, modulation converts ft to a bandpass form, in the neighborhood of the center frequency f c. This experiment provided a further test of the hypothesis that the effectiveness of the temporal mechanism depends upon the time spent close to frequency extremes during the modulation cycle. Bessel function is used in investigating the sidebands and bandwidth of fm signal.
Pm and digital modulation s p where 2 is the pkpk phase change in one symbol duration, t for digital signals the modulation index. The depth of modulation will be set to exactly 100% m 1. From the definition of frequency deviation, an equation can be written for the signal frequency of an fm wave as a function of time. In this manual, the information signal will be referred to as the message, which is. First, since fm only changes the frequency and not the amplitude of the carrier w ave, fm receivers can be built to ignore amplitude voltage changes.
Pdf frequency modulation fm ransariya divyesh academia. Ccsds recommendations for radio frequency and modulation systems earth stations and spacecraft references 1 procedures manual for the consultative committee for space data systems. Experiment 8 exercise 8 indirect method of generating fm signals. In this experiment, another widely used modulation technique will be introduced. You are free to choose the frequency and magnitude of the carrier and message signals. Unlike the propagation in free space, it is difficu. There are mainly two types of modulation namely synchronous and asynchronous modulation. Experiment 1 amplitude modulation and demodulation one with a frequency equal to the difference between the carrier and message frequencies in other words, for every sinewave in the message, the am signal includes a pair of sinewaves.
Basic concept of modulation the information source typically a low frequency signal referred to as the baseband signal carrier a higher frequency sinusoid example. Frequency modulation and demodulation experiment youtube. Find more similar flip pdfs like lab 5 amplitude modulation and demodulation. Fm broadcasting is capable of higher fidelitythat is, more accurate reproduction of the original program soundthan other broadcasting technologies, such as am broadcasting. Recall that we can write an equation for a sine wave as follows. Unlike most tims models, you are not free to choose parameters particularly frequencies. Vary the modulating frequency and amplitude and observe the effects on the modulated. Upon completion of the experiment, the student will. Any generic input signal can be written as v st atcos. Feed af modulating signal say, fm 1khz and em 5mv using a function generator. To study frequency modulation and determine its modulation factor. Complex message signals such as speech and music are made up of thousands sinewaves and so the am signal. Check pages 1 7 of lab 5 amplitude modulation and demodulation in the flip pdf version.
In the laboratory, you will use function generator as vco. You will gain an appreciation of the meaning of depth of modulation, and you will learn how to set other values of m, including cases where m 1. While amplitude modulation is achieved by varying e p, frequency modulation is realized by varying. Experiment 5 frequency modulation 1 objective to understand the principles of frequency modulation and demodulation. Therefore, the analysis is best carried out by taking the final steadystate response as reference and normalizing with respect to z jqf exp j ft. Ppt frequency modulation fm powerpoint presentation free. Modulation technique an overview sciencedirect topics. Amplitude modulation contents slide 1 amplitude modulation. Each radio station is assigned 200 khz, to transmit a stereo audio.
It is particularly used for sensitive acquisition of relatively weak biopotentials such as eeg, which requires very low inputreferred noise, less than 12. For the first part of the experiment you will model eqn. Analog communications lab manual bapatla engineering. Fm is a process in which the carrier frequency is varied by the amplitude of the modulating signal i. Test the system response by feeding a 1hz audio frequency tone to the fm sweep input pin. Each chapter includes background information which relates the experiment content to realworld applications. Amplitude modulation process in the flip pdf version. Modulation instability an overview sciencedirect topics. Dilip sir frequency modulation lab experiment communication lab the complete story of destiny. In this experiment, we will use a famous chip, the lm 566c to generate the fm signal. The information bearing signal the modulating signal changes the instantaneous frequency of the carrier.
Eed314 analog communication 20 spring experiment 4 group no grade student number and name student number and name student number and name experiment4 frequency demodulator preliminary work 1. The left and right channels each limited to 15khz are multiplexed into a single baseband signal using amplitude modulation using frequency modulation to shift the baseband. The carrier frequency, fc, should be larger than the highest spectral component in mt. Frequency modulation, or fm, is an important method of impressing information on a carrier. Exercise 51 generating ssb signals by the filter method 91. Frequency modulationsimulation experiment introduction. The 4%8% am amplitude modulation or the 23 pm phase modulation with the modulated frequency closed to the. Frequency modulation stimulated raman scattering microscopy. Frequency modulation and demodulation experiment tutorial by mr. Experiment 2 experiment 6 experiment dsb sc modulation. Herein, we report a new procedure for alignmentfree fmsrs utilizing polarization encoding. Frequency modulation free download usually, the frequency deviations from the final frequency wf are of interest.
Pdf psychoacoustic equivalence of frequency modulation and. Download tdm pulse amplitude modulation demodulation trainer st2102. Experiment 1 amplitude modulation and demodulation 1 amplitude modulation and demodulation preliminary discussion in an a mplitude m odulation am communications system, speech and music are converted into an electrical signal using a device such as a microphone. If they are to be tuned to different frequencies, then one of these frequencies must be 2. The transformation was used to characterize the stimuli in the ear canals of listeners in free field localization experiments. Fm signals have the same peak frequency deviation, then when mt is a sinusoidal signal set such that the pm and note. Adjust free run control to 90 khz and bring af amplitude control to minimum. The differentiator generates an output signal proportional to the first derivative of the input with respect to time. This is shown in block diagram form in figure 2 below. The transfer function of this circuit is vo rcdvidt. Cme312 lab manual frequency modulation experiment 8. Modulation instability using cw sources can be readily observed using an amplified source of about 100 mw. Effect of frequency mismatch of course, no one is interested in making frequency mismatch intentionally.
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