fm modulation and demodulation experiment pdf


FM Modulator Figure 1 illustrates the FM modulator circuit. BPSK modulation & demodulation (Matlab & Python . Add a 2V pp, 750Hz sinusoid as input, 12000Hz as carrier and set 3600 Hz/V as sensitivity. 3 Lab Part II: FM Demodulation To understand the characteristics of varactor diodes. MODULATION & DEMODULATION Questions and Answers pdf free download also objective multiple choice interview 2 mark important questions lab viva manual book. in the demodulation ur reference signal will be the modulated FM signal u want to demodulate, and hence the PLL is locked , ur output is taken from the VCO control voltage. A Binary Phase Shift Keying(BPSK) signal can be defined as where b ( t ) = +1 or -1 , fc is the carrier frequency, and T is the bit duration. modulation of a radio frequency (RF) carrier that has been frequency-modulated by an RC-filtered white- noise spectrum and corrupted in the channel by additive white Gaussian noise. The type of modulation is determined by the modulation depth, which for a fixed m(t) depends on the DC offset, V DC. 2 Out VCO Out CLA CLB Frequency demodulation is an essential process in telecommunication engineering. FM Demodulation a. 1) Slide 25 Experiment 8.2 FM Spectrum (cont. Muhamad Asvial, MEng., PhD Center for Information and Communication Engineering Research Electrical Engineering Department - University of Indonesia Kampus UI Depok, 16424 - Indonesia asvial@ee.ui.ac.id http://www.ee.ui.ac.id Fundamental design in Communication System Modulation Modulation The student is not allowed to pass this information to the demodulator so there is no prior knowledge of the random bit sequence being used in the demodulator. Copy of FM Modulation and Demodulation Circuit. The frequency modulation can be expressed as 72 . The following examples show AM waveforms for different modulation indices.

A simple FM demodulator, if it reproduces the message without distortion, will provide further confirmation that the VCO output is indeed an FM signal. . The zero-crossing-counter demodulator A simple yet effective FM demodulator is one which takes a time average of the zero crossings of the FM signal. Frequency Modulation and Demodulation Simulator. When a level of modulation is too low, the modulation does not utilize the carrier efficiently and if a level of . Shahjalal University of Science and Technology,Sylhet Experiment No. The amplitude of the carrier remains constant. A way to modulate digital data onto an analog carrier is to apply data-dependent phase shifts to the carrier signal, referred to as phase shift keying (PSK). 3. BPSK Modulation and Demodulation(Real time experiment . 16 Narrowband FM Only the J o and J 1 terms are significant Same Bandwidth as AM Using Eulers identity, and (t)<<1: Notice the sidebands are "sin", not "cos" as in AM Narrowband FM as a Phaser AM 8. We Acknowledge NITK and PALS for extending their support towards successful completion of this experiment . that time location. VARIOUS METHOD OF FM DEMODULATION Demodulation:-It is the process of deriving the original modulation signal from a modulated carrier wave. To understand the operation theory of voltage controlled oscillator (VCO). To study PLL 565 as frequency demodulator 5. Fm Modulation . . Describe fm demodulation circuit operation for the phase-shift and gated-beam discriminators and the ratio-detector demodulator. It involves converting a signal from one frequency to another frequency. The process of separating the original information or signal from the Modulated-carrier signal. Figure 3 suggests the principle. 2. Prelab 1 - AM Modulation - Prof. Dutton - EE133 Winter 2004 1 EE133 - Prelab 1 Amplitude Modulation and Demodulation 1 Introduction This week we will be taking a look at the amplitude modulation (AM) scheme. Adjust the amplitude of the square wave to obtain a peak frequency deviation of 1 kHz. Search. This signal . As a result, we can generate frequency modulated signals with the National Instruments . 1.Write a new code to generate an FM signal. transmission through the channel in consideration. Sampling THEORY, Pulse modulation. Add time domain and frequency domain scopes to the output (similar to the ones you had in the AM experiment). Demonstrate understanding of various amplitude modulation and demodulation techniques. 4. 2 Theory 2.1 Introduction A sinusoidal carrier c()t =Acos(ct +0) has three parameters that can be modified (modulated) according to an information signal f.(t) 1. Difference Between Modulation and Demodulation. The input data is a sine wave of frequency 4 Hz and amplitude 1 V. The frequency deviation is set to 50 Hz. nikspatel16. Frequency modulation, FM offers many advantages, particularly in mobile radio applications where its resistance to fading and interference is a great . Over the past decade the tremendous development of Wireless Communications has changed human life incredibly. Describe phase demodulation circuit operation for the peak, low-pass filter, and conversion detectors. To understand the operation theory of demodulation of FM and PM signal 2. Pll Circuit Using Ic 565 PDF Download playcube org. Analog Communication Systems 7-1 : Curriculum Objectives . Switch o the FM modulator (set the amplitude of VtSine to 0V), measure the total power of the signal and show that, at least 98% of power contained in Carson's bandwidth. View comm_exp2__FM_modulation.pdf from EEE 485 at Shahjalal University of Science & Technology. It should respond only to the frequency changes. EGYPT. The signal has a power , so that , where A represents the peak value of sinusoidal carrier. FM demodulation using PLL. In this experiment we will introduce the operations of phase discrimination method as demodulation. Browser not supported Safari version 15 and newer is not supported. Frequency Modulation (FM) is an important modulation scheme both because of its widespread commercial use, and because of its simplicity. The circuitry is designed to operate in the VLF band at a carrier frequency of 100 kHz. 3.Observe the output of the codec as you vary the frequency of the message. CHANNEL MODEL 0 Frequency Modulation Frequency modulation (FM) is the standard technique for high-fidelity communications as is evident in the received signals of the FM band (88-108 MHz) vs old analog FM Lds Garment Sizes ( t + ) then A is the amplitude of signal because the current oscillates between + A and - A (and A has units of amps) This course . To study amplitude demodulation by linear diode detector 3. To run the model, open the example by entering fmmoddemod at the MATLAB command prompt. 1. The FM demodulator must satisfy the following requirements: (i) It must convert frequency variations into amplitude variations. Frequency Modulation: The frequency modulation technique is used in computing, radio broadcasting, single processing, telecommunications. Frequency modulation (FM) is a type of modulation where the frequency of the carrier is varied in accordance with the modulating signal. Introduction: where the theory of the subject is reviewed. frequency and amplitude of modulating signal Frequency: Hz. In the following illustrations we will have a fixed message, V m cos m t and vary V DC to obtain different types of Double Sideband modulation. 1.2 Prelab Exercise 1. . Note, when a modulator is set up, V DC is fixed at a particular value. BPSK Modulation and Demodulation(Real time experiment . The illustration of FM demodulation is shown in Fig.2. To analyze the frequency spectrum of the demodulated FM and PM signal using MATLAB 4. 2. Single Side Band Demodulation Objective: In this experiment we will observe SSB Demodulation The experiment is setup as per the above block diagram. The input data is a sine wave of frequency 4 Hz and amplitude 1 V. It depends on the actual modulation type whether or not the spectra become similar with respect to shapes, symmetries, and bandwidths. The VCO portion of an LM565 is used to create the FM waveform, and an LM565 phase-locked-loop (PLL) operates as the FM detector. The main advantage of FM is its audio quality and immunity to noise. Cumsum models the integration operation for a digital signal, which means that the These were defined in the chapter entitled Analysis of the FM spectrum . Pulse shaping enables successful demodulation at the receiver side. In this experiment, we shall consider demodulation using envelope detector. A scheme for achieving this result was introduced earlier - the zero-crossing counter demodulator - and is shown modelled in figure 3. This experiment is in two parts, an FM modulator and an FM detector. I. Initialization: Copy the initialization files for the experiment into your Matlab working . Activity points. WBFM - Wideband Frequency Modulation Carson's Bandwidth Rule EELE445-14 Lecture 31. FM Demodulation / Detection Tutorial. : 08 Name of the Experiment: Implementation of demodulation of FM and PM signal using MATLAB coding Objective: 1. AM and FM MODULATION Lecture 5&6 Ir. A three-step process will allow you to become more familiar with FM: First, a frequency modulation system will be created and simulated using Simulink. Figure 3: An FM signal, and a train of zero-crossing pulses (iii) The demodulator circuit should be insensitive to amplitude changes. Connect the FM signal to the BPF (Use the 100 kHz channel filter module, set channel select to 3). A: AM Let A be a function of time, At()=A o (1+mcos M t), where the carrier frequency To run the model, open the example by entering fmmoddemod at the MATLAB command prompt. Experiment 2: Amplitude Modulation and Demodulation Objective Amplitude modulation (AM) is one of the simplest methods for modulating a sinusoidal carrier wave. . A PLL circuit is constituted by a phase comparator (the MC14046B actually contains two), a VCO, and a . . DSBSC modulation at a carrier frequency, kc, specified by the student. Modulation is the process of altering the characteristics of the amplitude, frequency, or phase angle of the high-frequency signal in accordance with the instantaneous value of the modulating wave. 2.3.2 Measurement of Power and Bandwidth of FM Signal 1. 2.2 FM Demodulation Using Slope Detection One type of conventional analog FM demodulation is achieved by determining the instantaneous frequency of an FM generated signal. . In this chapter we will learn about frequency modulation (FM) of signals: linear (LFM), sinusoidal (SFM) and arbitrary. To study sampling and reconstruction of Pulse Amplitude modulation system 6. In an AM signal, we now know that it is the amplitude (or the envelope) of the signal that is changed by the modulation signal. What is modulation and demodulation ?

exactly , the use of the PLL it to control the VCO so it track the phase an frequency of the reference signal. The output signal via a demodulator may describe the sound, images, or binary data. Enter the email address you signed up with and we'll email you a reset link. Each experiment, whenever applicable, contains the following sections: Objectives: where the expected achievements by the end of the experiment are stated. The modulation index is an important factor. This method is widely used in telecommunication devices to transmit voice without disturbances. The output will thus notbe a copy of the message. 4. . Modulation and demodulation process is the main process behind the communication system. Amplitute: V. Close Create . To explain the spectrum of . Perform envelope detection by connecting the BPF output to the Rectifier in the Utilities module then connect the Rectifier output to the Tunable LPF. ADVANCED MODULES . Note: The m-file uses the function cumsum of MatLab for FM modulation. Color TV for instance uses AM for brightness, FM for the sound and PM for the hue. Part IV: FM Demodulation Using Frequency Discriminator 1. 5 PAM Generation and Demodulation 27 6 DSB-SC using multiplier IC AD633 33 7 AM generation and Demodulation using AD 633 39 8 FM using 555 47 9 FM - Modulation and Demodulation using PLL 51 10 Mixer Circuit using BJT 57 A Quick Reference: Component Details 61 A.1 Intermediate Frequency Transformer . In this process, the amplitude of the carrier signal is varied so that it is proportional to the instantaneous amplitude of the modulating . Instructions. khouly. What is Demodulation? 2. . Slide 22 Experiment 8.1 FM Modulator (cont. disadvantages of frequency modulation, FM FM has poorer spectral efficiency than some other modulation formats: Some phase modulation and quadrature amplitude modulation formats have a higher spectral efficiency for data transmission than frequency shift keying, a form of frequency modulation. Learn how to build FM demodulator. In radio communication, Frequency modulation (FM) is the method of conveying information over a carrier wave by varying its frequency. Connect the Q1. Demodulation is the process of extracting the original information signal from a modulated carrier . Learn how to generate FM signal. As we have seen in this document, frequency modulation can be simplified to angle modulation with a simple integrator. Time-division multiplexing systems, Frequency division multiplexing systems. 2. Frequency Modulation(Simulation experiment).. Introduction . To study Pulse Amplitude Modulation a. using switching method b. by sample and hold circuit 7. Frequency modulation is widely used for radio transmissions for a wide variety of applications from broadcasting to general point to point communications. An FM signal is a member of the class defined as undergoing non-linear modulation. Yet, AM continues to be used today in many communication applications Demodulation: The Phase-Locked Loop. This experiment is in two parts, an FM modulator and an FM detector. The example, shows how the FM Modulator Baseband and FM Demodulator Baseband blocks are used to modulate and demodulate a sinusoidal signal. 16.1, which is the function of demodulator circuit. If it runs, great. Please use Chrome. : 02 Experiment Name: Frequency You will also study the influence of the frequency deviation constant on the signal bandwidth. Fig.2:Illustration of a frequency demodulation Procedure 1. 'Frequency Modulation amp Demodulation Techniques Scientech2203 June 18th, 2018 - Frequency modulation and demodulation techniques fm training kit for analog communication lab to . The example, shows how the FM Modulator Baseband and FM Demodulator Baseband blocks are used to modulate and demodulate a sinusoidal signal. 1) Slide 23 Experiment 8.2 Spectrum of an FM Signal Slide 24 Experiment 8.2 FM Spectrum (cont. Part 2: FM Demodulation. . 13,242. pll demodulator. . Feedback . Go back . Abstract. carrier. EXPERIMENT 5 Frequency Modulation 1 Objective To understand the principles of frequency modulation and demodulation. Quiz . This book is focused on special circuits dedicated to the RF level of wireless Communications. It would be an advantage if the experiment entitled Sampling with SAMPLE & HOLD (Volume D1) has also been completed. Experiment 5: Frequency Modulation In this experiment, the generation of frequency modulated signals by the direct method and the demod- . The FM output for a square wave looks like Frequency Shift Keying (FSK). Determine the permissible range in maximum modulation index for (i) Commercial Fm which has 30Hz to 15Hz mod frequencies (ii) Narrow . It is now necessary to de-embed the transmitted message, see Fig. The modulator The modulator outputs two files, the first with the modulated signal exactly N real elements long and the To study frequency modulation and determine its modulation factor 4. A phase-locked loop (PLL) can be used to create a complex but high-performance circuit for FM demodulation. . The relative height is 20log(M) dB, where M is the non-negative Modulation Index (a.k.a. It does this by combining a phase detector, a low-pass filter (aka "loop filter"), and a voltage-controlled oscillator (VCO) into a . FM Modulation and Demodulation Circuit. The VCO portion of an LM565 is used to create the FM waveform, and an LM565 phase-locked-loop (PLL) operates as the FM detector. Assign required parameters to each functional block. On the other hand, the theory may be applied to the demodulation or filtering of rather arbitrary types of stationary signal and noise processes. An FM demodulator would need to (re)combine all the sidefrequencies of an FM signal into a singlecomponent at message frequency. Experiment . is purely theoretical because they are the same in practice B 2(a) is a Simulink-based model of the DCM circuit given by (1), with analog modulating input Xs x as in Fig The proposed topology is well suited for a pipelined clocking scheme allowing increased oversampling ratios for both first and higher order modulators What does modulate mean? The demodulation of FM signals using PLL circuits is currently the most widely used method. Procedure . Slot Booking Procedure . Try to run it now. The signal has a power , so that , where A represents the peak value of sinusoidal carrier. Use a 100 Hz square wave to frequency-modulate the HP3314A VCO. Experiment 4 dB dB 1 frequency modulation 1 amplitude modulation 0 0 frequency modulation Filter Slope FM + AM Noise amplitude modulation AM Modulation signal+AM Noise Envelope detector Figure 1: FM Detection Using a Slope Detector (with a corner frequency 1 ) at 0 and take a frequency deviation of . Most forms of static and electrical noise are naturally AM, and an FM receiver will not respond to AM signals. Generation and detection of AM,DSB-SC, SSB and FM signals. Experiment # 7 FM Modulator Analog Communication Systems 7-1 : Curriculum Objectives I. 1) Slide 28 . Ans. Information bits are represented in a change of frequency of the carrier in binary frequency shift keying (BFSK). PREREQUISITES: completion of the experiment entitled The sampling theorem (Volume A1). . 3. Phase Comp. . 250+ TOP MCQs on Types of Frequency Modulation and Answers ; 250+ TOP MCQs on Single Tone Modulation and Answers ; 250+ TOP MCQs on Transmitter and Answers ; Course Out-Come: 1. 6a. Objective: FM modulation and demodulation Description: In this experiment you will design a FM modulator and a derivative based FM demodulator. digital modulation experiments include PCM encoding and decoding, line codes and digital carrier modulation (ASK and FSK). Frequency Modulation (FM): Here, the frequency of the carrier wave is changed according to the information signal In other words, the signal is multiplied by a square wave at the carrier frequency Although the sigma-delta modulator was first intro- In linear modulation, the amplitude of the transmitted signal varies linearly with the modulating digital signal, m(t) Observe the demultiplexed . shriapatil. ACHIEVEMENTS: generation and demodulation of pulse width modulated (PWM) and pulse position modulated (PPM) signals. Enter the email address you signed up with and we'll email you a reset link. . Chapter 7 FM Modulator (t) = Ac cos O(t) = Ac cos [2nfct + 2TCfA fx(l) dl] . This experiment deals with the basic performance of Frequency Modulation (FM). To design and implement the frequency modulator by using the voltage controlled oscillator. Become familiar with Bessel Function. Set the input signal. 61 EXPERIMENT 8 FREQUENCY MODULATION N0GSG. These will be on exact harmonics of the original message.