Repeat the experiment by mixing in a multitone modulating signal generated as in part 1. This principle is at the heart of amplitude modulation. The modulator outputs two files, the first with the modulated signal exactly n real elements long and the. To study sampling and reconstruction of pulse amplitude modulation system 6. Another method, which introduces more variables into the model, is explored in the experiment entitled. Each channel sharing scheme a set of basis vectors. Single sideband ssb is a common analog modulation scheme for. Demodulation part number and description qty dp73010 windows based dynamic signal an alyz ersoftw dp730101 rotating machinery package includes rpm based analysis, disk throughput, waterfall analysis and order tracking 1 1 1 1 1 amplitude modulation spectrum phase modulation spectrum 0500 hz baseband analysis.
Download modulation d amplitude demodulation d amplitude book pdf free download link or read online here in pdf. That could be the amplitude, phase, or frequency, which result in amplitude modulation am, phase modulation pm, or frequency modulation fm. Synchronous demodulation of amplitude modulation am. To study amplitude demodulation by linear diode detector 3. All they use the dsp for on fm is for audio processing. By the end of this experiment, the student should be able to. Pdf an analog method to modulate and demodulate signals is presented in. Build simple envelope detector for am demodulation. Frequency division multiplexing, fdma amplitude modulation and demodulation. Note that this is on the very low end of the recommended voltage range. To study and perform pulse position 6 to study and perform pulse code modulation and demodulation. Yet, am continues to be used today in many communication applications. Double sideband amplitude modulation with carrier setup 1a. This is based on a dsp, using dsp for demodulation of ssb, variable bandwidth filters, agc, noise reduction etc.
Amplitude demodulation matlab amdemod mathworks india. Id bet it could probably be pretty readily adapted i. In singlechannel efield sensing, the carrier we transmit is m, the sensed value is a, and the noise is n vectors. For example, the wavelength of a 1 ghz electromagnetic wave in free space is 30 cm. Students will explore the mathematical theory behind amplitude modulation and use the analog discovery 2 to visualize the effects of amplitude modulation in the time and frequency domains. All books are in clear copy here, and all files are secure so dont worry about it. Experiment with various carrier and modulation frequency settings. This perl program does a similar task, but for a different modulation scheme frequency shift keying. Figure 1 shows the block diagram of an am modulation and demodulation system. Connect frequency counter across the fm out sockets and measure free run span by rotating v r control to both. Then inner products dot products are 1 1 0 can interpret inner product as projection of vector 1 v1 onto vector 2 v2in other words, inner product of v1 and v2 tells us how much of vector 1 is there in the direction of vector 2. Group3 umang gupta 2010ee50564 indrabhushan 2010ee50548 vivekmangal 2010ee50566 jitendra kumar meena 2009ee50483 12912 experiment 2.
Normally detector can be classified as synchronous detector and asynchronous detector. Modulation is the process of altering the characteristics of the amplitude, frequency, or phase angle of the highfrequency signal in accordance with the instantaneous value of the modulating wave. In amplitude modulation, the amplitude signal strength of the carrier wave is varied in proportion to that of the message signal being transmitted. This lab introduces students to communications theory with amplitude modulation and demodulation. Indian institute of technology kanpur ee 381 electrical. Aly elosery october 25, 2010 this lab is divided into two parts.
The gain of the amplifier is such that it limits, and thereby removing all the modulation. Am modulation at a carrier frequency, kc, specified by the student. Multimedia tools downloads samplitude pro x suite by magix software gmbh and many more programs are available for instant and free download. To study frequency modulation and determine its modulation factor 4. Lab manual ssb modulation and demodulation experiment 7 ssb modulation and demodulation objectives. Simulation of analog modulation and demodulation techniques in virtual instrumentation and remote lab. Connect frequency counter across the fm out sockets and measure free run span by rotating vr.
Modulation allows us to transmit multiple signals in the same medium i. A continuouswave goes on continuously without any intervals and it is the baseband message signal, which contains the information. Jun 17, 2014 introduction to modulation and demodulation 1. Multimedia tools downloads samplitude by magix ag and many more programs are available for instant and free download. Eee2009eee2009 communicationscommunications contents introduction to communication systems analogue modulation am, dsbsc, vsb, ssb, fm, pm, narrow band fm, pll demodulators, and fll loops sampling systems time and frequency division multiplexing systems, nyquist principle, pam, ppm. Modulation is inherently a nonlinear process, and always gives rise to frequency components that did not exist in either of the two original signals amplitude modulated wave form if the amplitude modulated signal shown here is passed through a frequency analyzer, the following spectrum is the result. Introduction for am signals, the information is carried by the amplitude or envelope of the signal. Oct 30, 2017 amplitude modulation and demodulation. Modulation demodulation maps retrieves the digital information into from an analog waveform appropriate for transmission over the channel. To study and perform pulse amplitude modulation and demodulation.
Vectors and modulation cse 466 interfacing 3 spose m and n are orthogonal unit vectors. Amplitude modulation and demodulation objective amplitude modulation am is one of the simplest methods for modulating a sinusoidal carrier wave. In the case of bask, under noisefree conditions, z would be either. There are many ways to detect the envelope of am signals. In part i you will learn how to design an amplitude modulator am and in part ii you will be able to demodulate an am signal.
Dutton ee3 winter 2004 1 ee3 lab 1 amplitude modulation and demodulation 1 lab notes a word about power. Restoring or recovering the message signal from the received modulated waveform that is generally corrupted by noise types of am detectors. Eee2009eee2009 communicationscommunications contents introduction to communication systems analogue modulation am, dsbsc, vsb, ssb, fm, pm, narrow band fm, pll demodulators, and fll loops sampling systems time and frequency division multiplexing systems, nyquist principle, pam, ppm, and pwm. We will discuss these two types of detectors in this experiment. Vary the modulation signal amplitude calculate the corresponding changes in modulation index.
Read online modulation d amplitude demodulation d amplitude book pdf free download link book now. This is most convenient, cheapest and certainly the most elegant method of producing synchronous demodulation. Es442 lab 4 amplitude modulation and demodulation i. Customize the interface to suit your style and create beats and bass lines using a midi controller. Amplitude modulated signal can be represented by the following equation. Pdf amplitude demodulationbased em analysis of different. Modulation damplitude demodulation damplitude pdf book. Generally involve translating recovering the baseband digital information to from a bandpass analog signal at. In the fm demodulation what we need to recover is the variation of the.
These impulses cause the bearing race to ring at its natural frequency, just as a bell will ring when tapped. The purpose of this lab is for you to gain familiarity with the concepts of amplitude modulation and. Note that it looks like the double sideband modulated signal shown in figure 2 of the lecture notes. The continuous wave modulation techniques are further divided into amplitude modulation and angle modulation. Onoff modulation change the message signal to a square wave 2 khz and with vpp 4v. Laboratory manual principles of communication system lab ee226f ivth semester prepared by. The innovative point of this study is the elaboratio n of the method that enables the. Demonstrate the modulation and demodulation process of ssb. Set the modulation signal vst to a 500 hz sine wave with amplitude 2. This amplitude modulation is tested in ni usrp rio 2920 as transmitter. Amplitude demodulation applied to bearing analysis.
But for fm demodulation kenwood have chosen to convert to another if frequency 455 khz and add an fm demodulator chip. In amplitude modulation, the amplitude signal strength of the carrier wave is varied in proportion to that. Pdf simulation of analog modulation and demodulation. A bit stream is mapped to symbols during baseband modulation, each symbol say for qpsk represents two bits. Among the types of modulation techniques, the main classification is continuouswave modulation and pulse modulation. Sinusoidal modulation slowly increase the modulation signal voltage am over the range 0 v to 4 v i. For more info please visit our website or join the yahoo user group. The two common forms of analog modulation are amplitude modulation. To study and perform pulse width modulation and demodulation.
Then, students will use labview to program an am demodulator and use it to explore and visualize the effects. Matlab and labview have great modulationdemodulation toolkits, but we are looking for source code. Build simple am modulator by using crystal oscillator. The amplitude of the input signal controls the oscillation frequency of the vco output signal. This leaves a signal consisting only of the carrier and this can be used as the local oscillator signal in the mixer as shown in fig. Am modulation simply means the shifting of a signal frequency to another usually higher frequency. In modulation, one characteristic of a signal generally a sinusoidal wave known as the carrier is changed based on the information signal that we wish to transmit modulating signal. If a rolling element bearing has a defect such as a crack in one of the races, there will be an impact created every time a rolling element passes over it. There are many methods of generating am, and this experiment explores only one of them. To study and perform amplitude modulation and demodulation. The major blocks are the two multipliers and the low pass filter to remove the high frequency parts of the downmixed signal. In this experiment, a carrier signal and an audio modulating signal are applied to the modulator ic mc 1496 and the produced modulated waveform is observed. Remember that the am waveform appears like the diagram of view b and the amplitude variations of the peaks represent the original audio signal, but no modulating. Amplitude modulation am is a modulation technique used in electronic communication, most commonly for transmitting information via a radio carrier wave.
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