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Prof. Jen-Fa Huang, Fiber-Optic Communications Lab. National Cheng Kung University, Taiwan. Chapter V. Amplitude Modulations  An unmodulated sinusoidal.

University, Taiwan. Chapter V. Amplitude Modulations Figure 5-3. Amplitude modulation. Prof. Jen-Fa Huang, Fiber-Optic Communications Lab. National Cheng Kung University, Taiwan. Chapter V. Amplitude Modulations Figure 5-4. (a) Amplitude-modulated signal. (b) Information signal to/Idealized audio time-domain signal and baseband Fourier transform spectrum. (b) Fourier transform spectrum of m(t) amplitude modulated on a (cosine) carrier signal of frequency f c. Prof. Jen-Fa Huang, Fiber-Optic Communications/


Chapter 3: Pulse Modulation Digital Communication Systems 2012 R.Sokullu 1/68 CHAPTER 3 PULSE MODULATION.

.5 Bandwidth-Noise Trade-off 3.6 The Quantization Process Digital Communication Systems 2012 R.Sokullu Chapter 3: Pulse Modulation 37/68 3.3 Pulse Amplitude Modulation Definition: In Pulse Amplitude Modulation (PAM) the amplitudes of regularly spaced pulses are varied in accordance with the corresponding sample values of the continuous message signal; Note: Pulses can be rectangular or some other form. Digital Communication Systems /


Tuomas Tala 1/24 ITPA TC Meeting, Naka, Japan 31 March – 2 April 2009 NBI Modulation Experiments to Study Momentum Transport on JET + Status of TC-15 Tuomas.

16/24 ITPA TC Meeting, Naka, Japan 31 March – 2 April 2009 The Amplitude and Phase of the Rotation Very Different in Plasmas with Magnetic Ripple 2/2 Modulation of tangential PINIs at 1.5% ripple, #77091 1 st harmonic A 2 / Momentum Diffusivity and Pinch  Simulate ω  (using the time-dependent torque profiles from TRANSP) with JETTO transport code to fit the amplitude and phase of the modulated ω  together with steady- state ω  by trying different P r profile and v pinch profile  Step 1: Determination of/


1 ANGLE MODULATION EKT 231 : COMMUNICATION SYSTEM ANGLE MODULATION CHAPTER 3 Part II EKT 231 : COMMUNICATION SYSTEM EKT 231 : COMMUNICATION SYSTEM -2007/08(II)-

(VHF):88M-108MHz  Can transmit musical programs with higher degree of fidelity. EKT 231 : COMMUNICATION SYSTEM EKT 231 : COMMUNICATION SYSTEM -2007/08(II)- ANGLE MODULATION-PART II 6 FREQUENCY MODULATION PRINCIPLES In FM the carrier amplitude remains constant, the carrier frequency varies with the amplitude of modulating signal. The amount of change (the relative displacement of carrier frequency in hertz in respect to it un/


CHAPTER 2 AMPLITUDE MODULATION (AM). Principles of AM Definitions:  The process of changing the amplitude of a relatively high frequency carrier signal.

complex information signal fc Fc-fm1Fc-fm2Fc-fm3Fc+fm1Fc+fm2Fc+fm3 Cont’d..modulation index for complex information signal When several frequencies simultaneously amplitude modulate a carrier, the combined coefficient of modulation is defined as: m t =total modulation index/coefficient of modulation m 1, m 2, m 3, m n = modulation index/coefficient of modulation for input 1, 2,3, n Cont’d..Power calculation for complex/


TE4201-Communication Electronics 1 12. Digital Modulation Digital Coding and Digital Modulation Amplitude Modulation (AM,OOK,PRK) Frequency Shift Keying.

, performance monitoring, andperformance monitoring, and implementation costs.implementation costs. TE4201-Communication Electronics 5 Digital Modulation such as Amplitude Modulation(AM), Frequency Shift Keying(FSK), Quadrature Amplitude Modulation(QAM), impress the base-band information onto a carrier for radio transmission or to modulate the carrier. It emphasizes multilevel digital modulation Choosing a modulation technique depends upon getting high data rates within the rigidly defined bandwidth of a/


Sistem Telekomunikasi, Sukiswo, ST, MT 1 Pulse Modulation Sukiswo

destination over a physical transmission medium.  The four predominant methods of pulse modulation: –pulse width modulation (PWM) –pulse position modulation (PPM) –pulse amplitude modulation (PAM) –pulse code modulation (PCM). Sistem Telekomunikasi, Sukiswo, ST, MT 3 Pulse Modulation Sistem Telekomunikasi, Sukiswo, ST, MT 4 Pulse Width Modulation  PWM is sometimes called pulse duration modulation (PDM) or pulse length modulation (PLM), as the width (active portion of the duty cycle) of a/


AM,FM, and digital modulation systems

. A product detector is superior to an envelope detector when the input signal-to-noise ratio is small. 5.1 Amplitude Modulation because the total average normalized power of a band-pass waveform v(t) is given by Where “normalized” implies that/=707V during the times when there is no modulation. 5.1 Amplitude Modulation (1)the actual average power (2)then across the 50 Ω load, the PEP is: (3)The modulation efficiency would be: 5.1 Amplitude Modulation 5.1 Amplitude Modulation Fig. 4-2 Spectrum of AM signal 5/


ANGLE MODULATION CHAPTER 3 Review on Part 1 Part 2

Part 2 Review on Part 1 ANGLE MODULATION EKT 231 : COMMUNICATION SYSTEM CHAPTER 3 : ANGLE MODULATION Review on Part 1 ANGLE MODULATION Amplitude modulation (AM) Angle modulation (FM,PM) EKT 231 : COMMUNICATION SYSTEM CHAPTER 3 : ANGLE MODULATION Define the following….. Modulation Demodulation Amplitude modulation (AM) Angle modulation (FM,PM) Modulating signal Carrier signal Bandwidth EKT 231 : COMMUNICATION SYSTEM CHAPTER 3 : ANGLE MODULATION Introduction Angle modulation is the process by which the angle/


Introduction Pulse modulation consists essentially of sampling analog information signals and then converting those samples into discrete pulses and transporting.

source to a destination over a physical transmission medium. The four predominant methods of pulse modulation: pulse width modulation (PWM) pulse position modulation (PPM) pulse amplitude modulation (PAM) pulse code modulation (PCM). Pulse Modulation Analog Pulse Modulation Digital Pulse Modulation Pulse Amplitude (PAM) Pulse Code (PCM) Delta (DM) Pulse Width (PWM) Pulse Position (PPM) Pulse Amplitude Modulation (PAM): * The signal is sampled at regular intervals such that each sample is proportional to/


Wireless Networking Spread Spectrum Technologies Module-04 Jerry Bernardini Community College of Rhode Island 6/20/20151Wireless Networking J. Bernardini.

or vice versa CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 37 Analog Modulation Amplitude modulation (AM) – Carrier frequency varies in amplitude Frequency modulation (FM) – Carrier frequency varies in frequency Phase modulation (PM) – Carrier varies in phase CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini 38 Digital Modulation Advantages over analog modulation: – Better use of bandwidth – Requires less power – Better handling of interference from other signals/


Shiv Kalyanaraman Google: “Shiv RPI”

no ISI Example of eye pattern: Binary-PAM, SRRC pulse … AWGN (Eb/N0=10 dB) and no ISI Summary Digital Basics Modulation & Detection, Performance, Bounds Modulation Schemes, Constellations Pulse Shaping Extra Slides Bandpass Modulation: I, Q Representation Analog: Frequency Modulation (FM) vs Amplitude Modulation (AM) FM: all information in the phase or frequency of carrier Non-linear or rapid improvement in reception quality beyond a minimum/


Modulation                                                                 Digital data can be transmitted via an analog carrier signal by modulating one.

-> frequency of oscillation, the number of cycles per second F -> phase of the signal, representing the starting point of the cycle. To modulate the signal just means to systematically vary one of the three parameters of the signal: amplitude, frequency or phase. Amplitude modulation Amplitude modulation is the simplest of the three to understand. The transmitter just uses the information signal, Vm(t) to vary the/


Lecture 3 Data Encoding and Signal Modulation

( t ) = Ac + Am · cos ( 2 fm t) Power spectrum of DSBTC AM signal with sinusoidal baseband signal,  i = 100%, k = 1. DSBSC AM Sm ( t ) = Ac · cos ( 2 fm t) Amplitude Modulation of Digital Signals Baseband Signal Carrier Signal Baseband Signal with DC shift Transmitted Signal DSBTC AM signal with square wave baseband signal, i = 100%, k = 10.     DSBSC AM Binary Phase/


Modulation Modulation => Converts from digital to analog signal.

, the number of cycles per second F -> phase of the signal, representing the starting point of the cycle. To modulate the signal just means to systematically vary one (or more than one) of the three parameters of the signal: amplitude, frequency or phase. Amplitude modulation Amplitude modulation is the simplest of the three to understand. The transmitter just uses the information signal, Vm(t) to vary/


FREQUENCY MODULATION(FM )

b)The minimum bandwidth using Carson’s Rule. Sketch the frequency spectrum for (a), with actual amplitudes. Example 3.4 For an FM modulator with a modulation index m=1, a modulating signal Vm(t)=Vm sin(2π1000t), and an unmodulated carrier Vc(t) = 10sin(2π500kt),/always constant and the total average power is equal to the unmodulated carrier power, that is the amplitude of the FM remains constant whether or not it is modulated. FM Power Distribution (cont’d) In effect, in FM, the total power that is /


24 Apr06CS3282 Sectn 81 University of Manchester CS3282: Digital Communications Section 8: Carrier Modulated Transmission Convert binary data into form.

( (  C +  M ) t ) + 0.5 A cos( (  C -  M ) t ) upper sideband lower sideband  C = 2  f C, etc Where do we get ‘side-bands’ from? 24 Apr06CS3282 Sectn 811 Amplitude modulation Amplitude of sinewave can’t be  ve. Make bb purely +ve by adding constant. Always done with broadcast ‘am’ radio stations Instead of cos(  M t) use [1 + cos(  M t/


Inductive Logic Baseband Signaling and Modulation Eric L. Michelsen Part 1 of a 2-part presentation Part 1: Baseband Signaling.

level) symbol  A pair of bits in a single symbol is a dibit AKA 4-PAM (4-level Pulse Amplitude Modulation) Requires data transitions, or scrambling With scrambling, DC ~= 0 Used in SDSL, IDSL, ISDN BRI Other PAMs exist/third sentence, it would be: Bandwidth is not capacity! Inductive Logic 1/8/200325 Topics: Modulation Communication channels as filters Amplitude modulation Amplitude demodulation Quadrature multiplexing DMT ADSL Cosine review Sums of cosines Spectra Fourier transforms Baseband signaling Why /


ANGLE MODULATION CHAPTER 3. ANGLE MODULATION Part 1 Introduction.

t) = 10sin(2π500kt). Determine the number of sets of significant side frequencies and their amplitudes. Then, draw the frequency spectrum showing their relative amplitudes. Angle Modulation Part 2 FM Bandwidth Power distribution of FM Generation & Detection of FM Application of FM FM/ and the total average power is equal to the unmodulated carrier power, that is the amplitude of the FM remains constant whether or not it is modulated. FM Power Distribution (cont’d) In effect, in FM, the total power that /


COMMUNICATION SYSTEM EEEB453 Chapter 2 AMPLITUDE MODULATION Dept of Electrical Engineering Universiti Tenaga Nasional.

AM with small signals and must be amplified before transmission. - Diode Modulator,Transistor Modulator, PIN Diode Modulator, Differential Amplifier II) High-level modulators: - Produce AM at high power levels, usually in the final amplifier stage of a transmitter. - Collector Modulator, Series Modulator 17 Amplitude modulation with a diode. Amplitude Modulator – Diode Modulator 18 Amplitude Modulator – Diode Modulator  Diode modulation consists of a resistive mixing network, a diode rectifier, and an LC/


1 Lecture 1B (01/07) Signal Modulation Introduction Signal Analysis Advantages of Signal Modulation Amplitude Modulation Amplitude Modulation of Digital.

DC offset) 22 Power spectrum of DSBTC AM signal with sinusoidal baseband signal, i = 100%, k = 1. 23 24 Sm ( t ) = Ac · cos ( 2  fm t) DSBSC AM 25 26 Amplitude Modulation of Digital Signals Baseband Signal Baseband Signal with DC shift Carrier Signal 27 Transmitted Signal 28 DSBTC AM signal with square wave baseband signal, i = 100%, k = 10. 29 5V/


Chapter 4 Baseband Data Transmission & Digital Modulation Techniques.

phase, θ of the carrier are varied proportional to the information signal, a digital modulated signal is called Quadrature Amplitude Modulation (QAM) Cont’d... Amplitude Shift Keying (ASK) A binary information signal directly modulates the amplitude of an analog carrier. A binary information signal directly modulates the amplitude of an analog carrier. Where v ask (t) = amplitude shift keying wave v m (t) = digital information signal (volt) A/2 = unmodulated/


Signals and Emissions 1 G8 - SIGNALS AND EMISSIONS [2 exam questions - 2 groups] G8A - Carriers and modulation: AM; FM; single and double sideband; modulation.

A. Multiplex modulation B. Phase modulation C. Amplitude modulation D. Pulse modulation G8A04 What emission is produced by a reactance modulator connected to an RF power amplifier? A. Multiplex modulation B. Phase modulation C. Amplitude modulation D. Pulse modulation G8A05 What type of modulation varies the instantaneous power level of the RF signal? A. Frequency shift keying B. Pulse position modulation C. Frequency modulation D. Amplitude modulation G8A05 What type of modulation varies the instantaneous/


ANGLE MODULATION CHAPTER 3. ANGLE MODULATION Part 1 Introduction.

phase) of the carrier signal is changed in accordance with the instantaneous amplitude of modulating or message signal. Cont’d… classification into two types such as Frequency modulation (FM) Phase modulation (PM) Used for : Commercial radio broadcasting Television sound transmission Two/and the total average power is equal to the unmodulated carrier power, that is the amplitude of the FM remains constant whether or not it is modulated. FM Power Distribution (cont’d) In FM, the total power that is originally/


DEMODULATION OF FM SIGNALS Frequency demodulation involves a frequency discriminator, whose instantaneous output amplitude is directly proportional to.

of the instantaneous frequency of a sinusoidal carrier, and its amplitude is maintained constant. An amplitude limiter, following the IF section, is used to remove amplitude variations by clipping the modulated wave at the IF section output. The resulting rectangular /average noise power is small compared to the average carrier power at the envelope detector input. 2). The amplitude sensitivity k a is adjusted for a percentage modulation < 100 %. Using Eqs. (2.90) and (2.94), the figure of merit for AM is/


Chapter 4 part 2_a Digital Modulation Techniques.

Keying (ASK) Phase Shift Keying (PSK) Phase Shift Keying (PSK) Frequency Shift Keying (FSK) Frequency Shift Keying (FSK) Quadrature Amplitude Modulation (QAM) Quadrature Amplitude Modulation (QAM) Digital Modulation Techniques Digital modulation Digital modulation The process by which digital symbols are transformed into waveforms that are compatible with the characteristic of the channel. The process by which digital symbols are transformed into waveforms that /


Analog Modulation - Why Modulation? - Different analog modulation types - For each type:- - Mathematical presentation * Bandwidth * transmitted power -

s (t) = A (t) cos [Ө (t) ] Ө (t) = ω t + φ (t) ‘ A c cos ω c t ‘ is called unmodulated carrier Analog Modulation Digital Modulation Modulator m(t) Acos(2 πf c t +φ) modulated signal: s(t) Unmodulated carrier Modulation Types (Analog Modulation) Modulation Types (Digital Modulation) 1- Amplitude Modulation (A.M) Conventional Amplitude Modulation Consider a sinusoidal Carrier wave c(t) the unmodulated carrier. c(t) = A c cos 2 π f c t A/


Tunes modulation in a space charge dominated beam: The particles behavior in the “necktie” Space charge meeting – CERN - 21/11/2013 Vincenzo Forte Thanks.

.  E ∈ [-  E 1,  E 1 ] ->  phi) ∈ [0,  max ] Small amplitude in transverse + small  E cut around 0 = big tune modulation from 0 to max with small deviation from the segment that connects the bare tune and the maximum tune. Macroparticles with 0 phase/.  E ∈ [-  E 1,  E 1 ] ->  phi) ∈ [0,  max ] Small amplitude in transverse + small  E cut around 0 = big tune modulation from 0 to max with small deviation from the segment that connects the bare tune and the maximum tune. Macroparticles with 0 /


1 st semester 1436 / 1437. Modulation Continuous wave (CW) modulation AM Angle modulation FM PM Pulse Modulation Analog Pulse Modulation PAMPPMPDM Digital.

the transmission takes place at discrete time Introduction In digital pulse modulation, the message signal represented in a form that is discrete in both amplitude and time. The signal is transmitted as a sequence of coded pulses Pulse Amplitude Modulation (PAM) In the PAM, the amplitude of periodic pulse train is varied with a amplitude of the corresponding sample value of a continuous message signal. In/


PULSE ANALOG MODULATION 1BDG(44). A Continuous Time (CT) signal can not be processed by the digital processors. Hence to enable digital transmission of.

integer not exceeding fxu /Bx. Examples --- ##10. 18BDG(44) Pulse Analog Modulation – The modulating signal can modulate amplitude, width(duration) or position of the pulse. Three techniques are 1. Pulse Amplitude Modulation (PAM) 2. Pulse Width Modulation (PWM) 3. Pulse Position Modulation (PPM) 19BDG(44) Pulse Amplitude Modulation (PAM) – The amplitude of the pulse is directly proportional to amplitude of the modulating signal at the sampling instant. The width and position of the/


4.2 Digital Transmission Outlines □ Pulse Modulation □ Pulse Code Modulation □ Delta Modulation □ Line Codes.

signal (PAM) 3.Values converted to binary (Quantized) 4.Signal is digitally encoded for transmission (Encoded) 4 Steps Process Cont’d… □Analog signal is sampled. □Converted to discrete-time continuous-amplitude signal (Pulse Amplitude Modulation) □Pulses are quantized and assigned a digital value. □A 7-bit sample allows 128 quantizing levels. □PCM uses non-linear encoding, i.e/


ANGLE MODULATION CHAPTER 3. ANGLE MODULATION Part 1 Introduction.

the process by which the angle (frequency or Phase) of the carrier signal is changed in accordance with the instantaneous amplitude of modulating or message signal. also known as “Exponential modulation" Cont’d… classified into two types such as Frequency modulation (FM) Phase modulation (PM) Used for : Commercial radio broadcasting Television sound transmission Two way mobile radio Cellular radio Microwave and satellite communication system Cont/


Modulation and Multiplexing ICS 620. Overview Frequency Spectrum Modulation techniques Multiplexing--TDM vs FDM Multiple Access Signal formats.

Modulation Types of Analog Modulation Amplitude Modulation (AM) Amplitude Modulation (AM) Amplitude modulation is the process of varying the amplitude of a carrier wave in proportion to the amplitude of a baseband signal. The frequency of the carrier remains constant Amplitude modulation is the process of varying the amplitude of a carrier wave in proportion to the amplitude/main disadvantage of FM is the larger bandwidth it requires Amplitude Modulation Uses a higher frequency carrier Most efficient use of /


SIMS-201 What is Bandwidth and How it is Used.

wave in proportion to the amplitude of a baseband signal. The amplitude of the carrier remains constant Phase Modulation (PM) Another form of analog modulation technique which we will not discuss Amplitude Modulation Carrier wave Baseband signal Modulated wave Amplitude varying-frequency constant Frequency Modulation Carrier wave Baseband signal Modulated wave Large amplitude: high frequency Baseband signal Small amplitude: low frequency Modulated wave Frequency varying-amplitude constant AM vs. FM AM/


The Blazhko modulation of RRab stars Recent results Johanna Jurcsik Konkoly Observatory JENAM 2008, VIENNA, Austria Asteroseismology and Stellar Evolution.

Com 2007 2008 RR Gem 1935-36 1938-53 1958-59 1965-83 2004-05 Amplitude of phase modulation amplitude modulation Is Blazhko modulation a common property of RRab stars ? -- mmag amplitude of the modulation is also possible -- the modulation may occur temporarily We obtained extended multicolour light curves of large modulation Blazhko stars for the first time The light curves cover the whole pulsation light curve in different/


Sound Synthesis Part II: Oscillators, Additive Synthesis & Modulation.

: –Carrier components: come only from carrier –Sidebands: come from both carrier & modularion Amplitude Modulation Carrier: –Frequency: fc Modulating –Frequency: fm –Amplitude m*AMP Modulation index: m –m=0 no modulation –m>0 modulation –m=1 full modulation AMP fc m*AMP fm AMP + Amplitude Modulation (2) Carrier frequency fc –Unaffected by modulation index Sidebands fc+/-fm –Amplitude m/2*AMP –Energy split equally between lower/higher –When m=1, sidebands 6dB below/


Chapter : Digital Modulation 4.2 : Digital Transmission

Where N is the number of bits encoded into each signaling element. Digital Modulation Techniques Amplitude Shift Keying (ASK) Frequency Shift Keying (FSK) Phase Shift Keying (PSK) Quadrature Amplitude Modulation (QAM) Amplitude Shift Keying (ASK) A binary information signal directly modulates the amplitude of an analog carrier. Sometimes called Digital Amplitude Modulation (DAM) Where vask (t) = amplitude shift keying wave vm(t) = digital information signal (volt) A/2 = unmodulated carrier/


CHAPTER Modulation.

in the Representation of Analog Signals by Digital Signals * See earlier slides for details on PAM and PCM PAM or PDM Digitize Computer Processing PCM Encode Modulation Techniques Pulse Amplitude Modulation (PAM) Pulse Code Modulation (PCM) Pulse Duration Modulation (PDM) Pulse Duration Modulation 110 001 101 6 1 5 Note: pulse duration is proportional to The height of the analog wave Salient Points of Pulse Duration/


Chapter 5 – Signal Encoding and Modulation Techniques

decreases BER and decreases bandwidth Efficiency MPSK: Increasing M increases BER and increases bandwidth efficiency 42/45 Quadrature Amplitude Modulation (QAM) QAM used on asymmetric digital subscriber line (ADSL) and some wireless standards combination of ASK and/same carrier frequency use two copies of carrier, one shifted by 90° each carrier is ASK modulated Quadrature amplitude modulation (QAM) is a popular analog signaling technique that is used in the asymmetric digital subscriber line (ADSL),/


Carriers and Modulation

is sampled at regular intervals and translated into a binary number. The difference between the original analog signal and the translated digital signal is called quantizing error. Pulse Amplitude Modulation Pulse Amplitude Modulation Pulse Amplitude Modulation Pulse Amplitude Modulation For standard voice grade circuits, the sampling of 3300 Hz at an average of 2 samples/second would result in a sample rate of 6600 times per second. There/


Amplitude Modulation Wei Li weili@ieee.org CSULB May 22, 2006.

Band) CSULB May 22, 2006 AM Transmitter and Receiver CSULB May 22, 2006 AM Transmitter and Receiver CSULB May 22, 2006 Summary Next Class…. DSB, SSB, VSB…… FM, PM Modulation, Amplitude Modulation Modulation Index, Modulation Depth Demodulation of AM signals Calculation and Examples Math: AM Time domain+Frequency domain Calculation: AM Power, AM Demodulation Next Class…. DSB, SSB, VSB…… FM, PM CSULB May 22, 2006


Chapter 7 Solution for Wave Interactions Using A PMM 7.1 Waves Advancing on Currents 7.2 Short Waves Modulated by Long Waves 7.3 Wave Modulation Revealed.

Waves on steady and uniform currents: Doppler‘s effect Waves on unsteady and non-uniform currents: Modulation Wave frequency, wavenumber vector and amplitude changes Peregrine (1976) Figure 7.1 Wave advance over a converging and diverging velocity field A converging/ of the SW, the large magnitude resulting from the small denominators does not affect the amplitude of the 1 st - harmonic SW. Since the modulated short-wave frequency and wavenumber are related to, we examine if they are convergent. Increases/


Wireless Networking Spread Spectrum Technologies Module-05

0 bit or vice versa CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini Analog Modulation Amplitude modulation (AM) – Carrier frequency varies in amplitude Frequency modulation (FM) – Carrier frequency varies in frequency Phase modulation (PM) – Carrier varies in phase CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini CWNA Guide to Wireless LANs, Second EditionCCRI J. Bernardini/


Angle Modulation.

Definitions -Frequency Deviation is maximum departure of instantaneous freq. of FM wave from career frequency Maximum Freq of FM is fmax= fc+ is independent of modulating freq. and proportional to only amplitude of information Modulation index is proportional to deviation and inversely proportional to modulating freq. This decides the BW of the FM wave also decides the no of side bands In FM the/


8/16/20021 Modems Key Learning Points Fundamentals of modulation and demodulation Frequency Domain Representation Time Domain Representation M-ary Modulation.

°)  2 bits/signal 8/16/200238 QAM – (quad amplitude modulation) Combine ASK & PSK QAM-16 levels per signal element  4-bits per symbol - 12 phase levels - 4 amplitudes levels - different amplitude associated with adjacent phases - 48 total signal levels  possible /points  grey coding – adjacent symbols differ by 1 bit  offset phase angles for adjacent amplitude 8/16/200241 All modulation schemes scramble & descramble reduces probability that consecutive bits in sequence are in adjacent bit positions - /


"All of RF is Truly FM" SIGA2800 Basic SIGINT Technology

), and phase. Types of Modulation Amplitude Modulation Phase Modulation With very few exceptions, phase modulation is used for digital information. Frequency Modulation These two constitute angle modulation. Types of Modulation Types of Information Analog Digital Carrier Variations Amplitude Frequency Phase These two constitute angle modulation. (Objective #1) Information / Baseband Modulation Process Modulating Signal Modulator Information / Baseband Modulated Signal The modulation general process is the/


COMMUNICATION SYSTEM EECB353 Chapter 2 Part II AMPLITUDE MODULATION

Chapter 2 Part II AMPLITUDE MODULATION Azlina Abdullah Dept of Electrical Engineering Universiti Tenaga Nasional AM Voltage Distribution Mathematically an unmodulated carrier can be described as: where vc(t) = time-varying voltage for the carrier Ec = peak carrier amplitude (volts) fc = carrier frequency (hertz) But Vmax = Ec + Em , then the instantaneous modulated amplitude: where = amplitude of modulated wave Em = peak change in the amplitude of the envelope (volts/


Modulation Techniques for Mobile Radio

carrier frequency. Demodulation is the process of extracting the base band message from the carrier. Modulation Techniques Analog Modulation (First Generation (1G) Mobile Radio) Digital Modulation (2G, 3G and 4G systems) Review of Analog Modulation Techniques Amplitude Modulation (AM) Message Signal -- Carrier Signal -- AM Signal -- AM Spectrum Carrier Sidebands AM Parameters Modulation Index -- Bandwidth -- Total Power in AM Signal Power in the carrier -- Single Singleband AM Signal/


1 WCA102 Fundamentals of Digital Modulation Digital Modulation – Introduction Digital Modulation in Wireless Communications.

 Repeatable, more easily produced  Reduced device size Modulation for Wireless  Media  Carrier  The 3 essential parameters  Amplitude value A(t)― Amplitude Modulation  Frequency value f(t)― Frequency Modulation  Phase value φ(t)― Phase Modulation V(t) = A cos(2πfc t + Φ) Analog ModulationAmplitude Modulation  AM radio  Frequency Modulation  FM radio, TV audio signal  Phase Modulation  TV color image signal (including Amplitude Modulation) Transmission of a Digital Message  Basically, it’s/


1 16.546 Computer Telecommunications: Modulation and Data Encoding Professor Jay Weitzen Electrical & Computer Engineering Department The University of.

multiple channel, we combine the samples of all channels into a single signal called the PAM signal (Pulse Amplitude Modulation signal) In American systems we sample 24 channels In the European systems 30 channels are sampled 37 Quantization To/4A) Voice data limited to below 4000Hz Require 8000 sample per second Analog samples (Pulse Amplitude Modulation, PAM) Each sample assigned digital value 76 Pulse Code Modulation(PCM) (2) 4 bit system gives 16 levels Quantized –Quantizing error or noise –/


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