Preparation of a virtual toolkit for communication systems. If you are using ni hardware, with the drivers you would have got a cd containing which contains examples for. Modulator and demodulator labview vibpsk,qpsk,16qam,64qam. Ni labview modulation toolkit help labview modulation.
Quadratureamplitude modulation qam quadraturephase shiftkeying qpsk upconversion. For a perfect modulation, the value of modulation index should be 1, which implies the percentage of modulation should be 100%. The second is to investigate classical analog amplitude modulation and the envelope detector. Pdf a labviewbased analog modulation tool for virtual and.
You can download pdf versions of the spectral measurements. Implementation of analog modulation techniques using. Ngn pulse code modulation the advent of highspeed voice and data communications has brought about the need for a fast medium for transporting the information. Pdf implementation of analog modulation techniques using. Set g so that the sinewave peaks just fall to zero. For future reference, this manual is available both electronically and in print. In this video tutorial, we will provide a general introduction of terms of communication systems with emphasis on wireless transmission and reception. Java project tutorial make login and register form step by step using netbeans and mysql database duration. Am modulation we can see that an upconversion mixer is a natural amplitude modulator if the input to the mixer is a baseband signal at, then the output is an am carrier vot atcos. The first is to gain experience in implementing a white noise source in labview. Dutton ee3 winter 2004 1 ee3 lab 1 amplitude modulation and demodulation 1 lab notes a word about power. This lab introduces students to communications theory with amplitude modulation and demodulation. The second is to investigate classical analog amplitude modulation 1 and the effects of noise on the modulated signal envelope.
An am modulator is constructed usingthe analog devices ad534 four quadrant multiplier, and the properties of the resultingsignal are examined using labview. Frequency modulation fm is a form of modulation in which changes in the carrier wave frequency correspond directly to changes in the baseband signal. 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. In this experiment, the properties and characteristics of amplitude modulated am signals and their frequency spectra are examined. Introduction to communication systems using national. It is somewhat similar to gnu radio in that programming is done by connecting a series of various blocks together, each of which performs some function. The basic theory and equations behind amplitude modulation are relatively straightforward and can be handled using straightforward trigonometric calculations and manipulation. Run labview and open the transmitter and receiver vis that you created in the prelab. Instead of outputting digital values that are either low 0v or high 5v. Construct a labview vi that transmits and receives a signal in software using fm. Note that this is on the very low end of the recommended voltage range. Where m is the modulation index, wc is the carrier frequency, x.
The fmmodulated signal has its instantaneous frequency that varies linearly with the amplitude of the message signal. Types of modulation 6 flynnkatz 7810 analog modulation amplitude modulation, am frequency modulation, fm double and single sideband, dsb and ssb digital modulation phase shift keying. It covers bpsk, qpsk, 16qam and 64qam modulation techniques. Phasemodulated pm signal generation national instruments. This virtual instrument is designed to work with rf communications hardware from national instruments. Each tutorial in this series teaches you a specific topic of common measurement applications, by explaining the theory and giving practical examples. Basic concept of modulation the information source typically a low frequency signal referred to as the baseband signal carrier a higher frequency sinusoid example. If you think youve messed something up, the easiest way to fix it for what were doing today is to start over. If the received carrier phase is assumed to be constant, each of the seven reference values will have to be shifted only. C67 dsk implementation using cc for this part of the lab, you will demodulate the am signal generated by the arbitrary waveform generator on your lab bench. This feature provides microcontrollers by a mean of, seemingly, outputting analog values of voltage between 05v. Pulse width modulation pwm tutorial deepblue embedded. This video tutorial has been designed to suit the curriculum of cbse class 12 students.
The rtlsdr is compatible with labview via a simple rtlsdr interface. Pcm based digital communication system using labview. Lab 5 amplitude modulation and demodulation pages 1 7. T background pcm modulation is a kind of source coding. This tutorial discusses analogmodulation techniques with the labviewbased analogmod package, developed for the illustration of different modulation types in undergraduate labs.
An interface is constructed that allows users to choose the different modulation and also allows to vary the amplitude, frequency, phase, frequency modulation index and phase modulation index. There is my basic am modulator design with labview in youtube link. Do not save any changes you may have made to the builtin vis were using such as hp34970a initialize. Simply close all your labview windows, saving only your work, and exit labview. It is still in use today in a variety of systems, including, of course, am broadcast radio. The front panel of the labview gives the user interface and the block diagram is for designing the system. This example demonstrates how to generate a phasemodulated signal using a nifgen waveform generator. I want to analyse the am signal using the card pci4474,i want todemodulation the signal using the software,i dont know how to realizeit. The idea is simple, though the notion that it can be used to modulate signals. Musical signal processing with labview modulation synthesis.
Intro to generation of ask amplitude shift keying ask in the context of digital communications is a modulation. Then, students will use labview to program an am demodulator and use it to explore and visualize the effects. This program is a shipping example vi included with the modulation toolkit for ni labview. Advanced data acquisition series pulse width modulation in ni labview using nidaqmx back to document this document is part of the advanced data acquisition series, consisting of tutorials and interactive presentations on how ni labview, nidaq software, and national instruments hardware can be used to easily create advanced daq applications. Look for examples help find examples on modulation or amplitude modulation. Labview modulation toolkit documentation ni labview modulation toolkit help labview modulation toolkit. Advanced data acquisition series pulse width modulation. Labview is a popular visual programming environment often used in industry and by engineers for test, automation and control applications. Labview digital signal processing and digital communications. Am modulation where the amplitude of the carrier does not depend on the value of the modulating signal. An am modulator is constructed using the analog devices ad534 four quadrant multiplier, and the properties of the resulting. Bpsk, qpsk, msk frequency shift keying, fsk quadrature amplitude modulation, qam.
Connect the computer to the usrp using an ethernet cable. To understand the theoretical foundations of analog communications as well as of doublesideband amplitude modulation and demodulation dsbam to design the simulink model of the dsbam to analyze each signal in time and frequency domains using time scope and spectrum analyzer. Ni now has a modulation, demodulation toolset, which may be. It provides link to download labview vi source code. In this experiment, the properties and characteristics of amplitude modulated amsignals and their frequency spectra are examined. This labview tutorial demonstrates am, fm and pm analog modulation using real audio signal contained in. A vis can read out to a single sensor, emulate the frontface of. Notice that the sine wave will move up and down as the dc is varied, its mean value equalling the dc value.
Figure 7 labview vis that you need to complete the am modulation and demodulation block diagram below figure 8 completed am modulation and demodulation block diagram am demodulation. Modulator and demodulator labview source code qpsk stands for quadrature phase shift keying and qam quadrature amplitude modulation. Review pulse train bandwidth s ingle pulse of duration. Pdf lab manual, labview code instructor resources labview code solutions. Labview is designed to build graphical user interfaces guis for laboratory instrumentation also called virtual instruments vis. Slide 6 narrow band fm slide 7 bandwidth of an fm signal. To generate and demodulate an amplitude shift keyed ask signal and a binary fsk signal. The modulation techniques used for discussion are amplitude and frequency modulation followed by demodulation.
The modulation toolkit supports ask, fsk, msk, psk, qam, cpm, pam, am, fm, and pm modulation formats, and is capable of if to iq conversion, iq visualization, and adding common signal impairments. Construct a labview vi that transmits and receives a signal in software using am. How can i modulate am any voice or sound files on labview. Lab 5 amplitude modulation and demodulation prelab 5. The main objective of our paper is to perform demodulation using labview and also realize both modulation and demodulation using c6748 kit. I am a beginner at labview so can someone please give me some suggestions. Essentially an amplitude modulated wave consists of a radio frequency carrier a sine wave at one frequency, typically in the radio frequency portion of the spectrum.
The pwm signal plot looks something like as shown in the diagram below. As part of the modulation practices we simulated this am modulator circuit to test the effects of the modulation quotient in the signal we plan to transfer. Modulator and demodulator labview source codebpsk,qpsk,16qam,64qam. In this video you will see amplitude modulation using different type of signals and channels. I need help in modulating a signal using fsk modulation using labview 7. Then, students will use labview to program an am demodulator and use it to explore and visualize the. Lets expand a sinusoid that has am and pm vot atcos. Slide 3 discretetime fm modulator slide 4 single tone fm modulation slide 5 single tone fm cont.