# What is digital modulation?

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In digital modulation, an analog carrier signal is modulated by a digital bit stream. Digital modulation methods can be considered as digital-to-analog conversion, and the corresponding demodulation or detection as analog-to-digital conversion. The changes in the carrier signal are chosen from a finite number of M alternative symbols (the modulation alphabet).  Fundamental digital modulation methods These are the most fundamental digital modulation techniques:
• In the case of PSK, a finite number of phases are used.
• In the case of FSK, a finite number of frequencies are used.
• In the case of ASK, a finite number of amplitudes are used.
• In the case of QAM, a finite number of at least two phases, and at least two amplitudes are used.
In QAM, an inphase signal (the I signal, for example a cosine waveform) and a quadrature phase signal (the Q signal, for example a sine wave) are amplitude modulated with a finite number of amplitudes, and summed. It can be seen as a two-channel system, each channel using ASK. The resulting signal is equivalent to a combination of PSK an In digital modulation, an analog carrier signal is modulated by a digital bit stream. Digital modulation methods can be considered as digital-to-analog conversion, and the corresponding demodulation or detection as analog-to-digital conversion. The changes in the carrier signal are chosen from a finite number of M alternative symbols (the modulation alphabet).  Fundamental digital modulation methods These are the most fundamental digital modulation techniques:
• In the case of PSK, a finite number of phases are used.
• In the case of FSK, a finite number of frequencies are used.
• In the case of ASK, a finite number of amplitudes are used.
• In the case of QAM, a finite number of at least two phases, and at least two amplitudes are used.
In QAM, an inphase signal (the I signal, for example a cosine waveform) and a quadrature phase signal (the Q signal, for example a sine wave) are amplitude modulated with a finite number of amplitudes, and summed. It can be seen as a two-channel system, each channel using ASK. The resulting signal is equivalent to a combination of PSK and ASK. In all of the above methods, each of these phases, frequencies or amplitudes are assigned a unique pattern of binary bits. Usually, each phase, frequency or amplitude encodes an equal number of bits. This number of bits comprises the symbol that is represented by the particular phase. If the alphabet consists of M = 2N alternative symbols, each symbol represents a message consisting of N bits. If the symbol rate (also known as the baud rate) is fS symbols/second (or baud), the data rate is NfS bit/second. For example, with an alphabet consisting of 16 alternative symbols, each symbol represents 4 bits. Thus, the data rate is four times the baud rate. In the case of PSK, ASK or QAM, where the carrier frequency of the modulated signal is constant, the modulation alphabet is often conveniently represented on a constellation diagram, showing the amplitude of the I signal at the x-axis, and the amplitude of the Q signal at the y-axis, for each symbol. d ASK. In all of the above methods, each of these phases, frequencies or amplitudes are assigned a unique pattern of binary bits. Usually, each phase, frequency or amplitude encodes an equal number of bits. This number of bits comprises the symbol that is represented by the particular phase. If the alphabet consists of M = 2N alternative symbols, each symbol represents a message consisting of N bits. If the symbol rate (also known as the baud rate) is fS symbols/second (or baud), the data rate is NfS bit/second. For example, with an alphabet consisting of 16 alternative symbols, each symbol represents 4 bits. Thus, the data rate is four times the baud rate. In the case of PSK, ASK or QAM, where the carrier frequency of the modulated signal is constant, the modulation alphabet is often conveniently represented on a constellation diagram, showing the amplitude of the I signal at the x-axis, and the amplitude of the Q signal at the y-axis, for each symbol.
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# On a 94 Deville the Digital gas indicator flashes E all the time even when tank is full. Is there a module that controls this your fuel door won't open when you push the button either. checked fuses.?

Answer . \nI had the same problem with my 94 deville except it was just one of the fuses under the hood but i alos know that sometimes when this happens your ground wire (which should be under the car on the gas tank has came loose. I would check these things first. As for your fuel door i have t (MORE)

# Where is the computer module located on the 1998 Ford looking for the five digit code set for key less entry system?

Answer . \nWhere your jack is stored in the rear left panel. Look towards the front of this panel. There is a metal box that controls your locking mechanism. The factory code for your keyless entry is on the backside of this. It is hard to get to, but by using a mirror, flashlight, and maybe loo (MORE)

# How do you do modulation BPSK with a digital input the modulation must use matlab simulink?

BPSK Modulation can be done by using a multiplier. Digital data must be multiplied with the carrier frequency.. In matlab simulink use a multiplier block to one input apply a sinusoidal generator &. to the other a Pulse generator

# What is modulator?

Any device or circuit by means of which a desired signal is impressed upon a higher-frequency periodic wave known as a carrier. The process is called modulation. The modulator may vary the amplitude, frequency, or phase of the carrier.

# What is modulation?

The process in which massege is place over a carrier signal is known as modulation.This process take place in transmitter.Demodulation is its opposite it take place in receivers.. By m.hashim.B.sc electronics mardan. . it is the process in which the carrier signal is adjusted according to the me (MORE)

# Exactly where to find the factory set 5-digit keyless entry code that is supposedly taped to the computer module in my 2005 Mercury Grand Marquis?

It's usually on the left side inside of the trunk. Some owners remove that one and place a sticker inside of the glove box or write it in the owners manual.. The sticker in the truck is on the left side on the bar that raises the truck lid. If its there, it'll be easy to see.. If those options don (MORE)

# What is a digitizer?

Digitizers convert analog or physical input into digital images. This makes them related to both scanners and mice, although current digitizers serve completely different roles.

# What does a module do?

A module is a small electronic component. This controls andmonitors a number of actuators inside the compartment of an engine.

# What is a module?

It is a standard or unit of measurement. . For the source and more detailed information concerning this subject, click on the related links section indicated below. .

# What is modulation and why is it needed?

It might be helpful to have a working definition of modulationbefore making a statement as to why it is needed. In fact, with anunderstanding of what modulation is, it will be obvious why it isincluded in electronic communications. Modulation is the "message" or the "intelligence" that is impressed (MORE)

# What is a digital?

When an appliance is digital, it basically means that all its functions are based on a code of binary digits. . http://wiki.answers.com/#hw-item-471 . http://wiki.answers.com/#hw-item-472 . http://wiki.answers.com/#hw-item-473 . http://wiki.answers.com/#hw-item-475 . http://wiki.answers (MORE)

# What is Modulation index in Frequency modulation?

Modulation Index is the ratio of the maximum deviation frequency to the frequency of modulation. In other words it is the ratio of the spread in frequency spectrum to the frequency that was used to modulate the carrier. For FM, modulation index is given by the formula mf= df/f where, mf=modulation (MORE)

# What are the goals for digital modulation?

Simply put, digital modulation is designed to maximize the amount of data we can put through a system per unit of time while maintaining the integrity of that data. Those are the two primary goals.

# What is digit?

Take your pick they are: 0 1 2 3 4 5 6 7 8 and 9

# What are the advantages of digital modulation over analog modulation?

1)digital modulation can easily detect and correct the noise. where as analog modulation has little complexity 2)security is more in digital modulation 3)digital modulated signal can traverse a long distance compared to analog modulation

# What is the modulation?

sending data between two electronic or networking devices by using modem or other devices, using data forms (a typical data form ,means set of frequences) send a modem or other devices. sending data into typical forms is caled modulation of data.when receiving data ,equipments process demodulation.. (MORE)

# What is the difference between analog and digital modulation Does it depends on baseband signal?

The basic difference is that in analog modulation the modulating signal is analog signal and in digital modulation it is in digital form.

# Give the example of symbol baud rate bit rate in digital modulation?

bit rate is the no. of bits transmitted per sec and baud rate is the measurement of the no of times per sec a signal changes in ta communication channel.. . eg if bit rate is 3400/s ,it means it can transfer 3400 o's or 1's per sec . whereas if baud rate is 3400/s ,it means channel changes states (MORE)

# What is a modulation?

one kind of frequency when changed into another is known as modulation modulation - process in which amplitude, frequency and phase of the carrier wave is made to vary in accordance with an information-bearing signal wave - the modulating wave.

# How is analog modulation different from digital modulation?

i refered modulation is the sequence of message in to analog symbol( Simon haykin ,communication systems),,but i am not clear with this,couul u pls clarify?

# What is the two level digital puse amplitude modulation?

In Pulse Amplitude Modulation, amplitude of pulse varies with signal. Theoretically in analog modulation there infinite levels of amplitudes or continuous amplitude. Two level PAM is digital modulation where only 2 number of levels are there. Thus signal is quantized to two discrete levels.

# What are the differences between analog and digital modulation?

There is no modulation of a Digital Circuit. Modulation is placing information onto an analog circuit to transport that information to a distant location to be decoded/demodulated. Having said that, you can modulate a digital signal in dozens of ways, (Modem) and you can also modulate an a (MORE)

# What is the difference between analog pulse modulation and digital pulse modulation?

Analog Pulse modulation is discreet in time but the formation is transmitted in continuous form. In digital pulse modulation, not only the time axis is discreet but the information is also in digital form. Examples of Analog PM are PAM and PTM i.e pulse amplitude and pulse time modulations respect (MORE)

# Difference between digital transmission and digital modulation?

The Difference of two is only first digital has a transmission and second digital has modulation.....thats all....i think that's too clear ha...

# What is Modulation index in amplitude modulation?

The modulation index of a modulation scheme describes by how much the modulated variable of the carrier signal varies around its unmodulated level

the only advantage is generation of ASK is very much easy. as,it is known as on-off keying. otherwise,it is not advantageous,as,it has highest rate of probability of error......

# What is the need of digital modulation scheme?

The aim of digital modulation is to transfer a digital bit stream over an analog bandpass channel, for example over the public switched telephone network (where a filter limits the frequency range to between 300 and 3400 Hz) or a limited radio frequency band.

# Difference between analog modulation and digital modulation?

Analog is when audio or video is taken and translated intoelectronic pulses. Digital modulation is when audio or video isbroken into binary codes and then transferred to the viewingdevice.

# Pulse Position modulation is digital or not?

Pulse position modulation can be analog or digital, it depends on the signal and/or the modulator used to obtain the modulation. If an analog signal is applied at the input of the modulator, the position of the pulse can assume an infinity of different timing states (the signal vary continuously) a (MORE)

# What is the modulating frequency of amplitude modulation?

Amplitude modulation refers to the changes in amplitude of the carrier signal due to the changes in amplitude of information signal

# What is digitals?

The term digital signal is used to refer to more than one concept. It can refer to discrete-time signals that are digitized, or to the waveform signals in a digital system. Digital signals are digital representations of discrete-time signals, which are often derived from analog signals. As a simple (MORE)

# What are modules of oracle?

Oracle sells many functional modules which use the Oracle RDBMS asa back-end, notably Oracle Financials, Oracle HRMS, Oracle SCM,Oracle Projects, Oracle CRM, Oracle Procurement.

# What is need for modulation?

Need of Modulation:To transfer the message signal from one site another sitewithout any loss for that we are using modulation.Modulation classified in three types.1.Amplitude modulation.2.Frequency Modulation.3.Phase Modulation.

# Why is modulation necessary?

modulation is necessary for transmitting low frequency signal to long range with desired qualitative information

# Exactly where to find the factory set 5-digit keyless entry code that is supposedly taped to the computer module in your 2008 Mercury Grand Marquis?

Just a long shot, but try looking in the trunk all around. Sometimes you will find the sticker there.

# What are the three modulation techniques used for digital television transmission?

Three different modulating techniques are emploed to provide digital television (i.e. satellite, cable, UHF ) and these are known as DQPSK, QAM and COFDM. Each technique is a variation of phase modulation. QAM also takes advantage of amplitude as well as phase changes.

# What is data module and support module?

support module provides an auxiliary set of instructions that can be used in conjunction with the main software program. It is not designed to be run by the computer user. Instead, these modules are "called" by the computer program as needed. data module comprises any data that is necessary for a (MORE)

# Is modulation needed for digital data transmission?

Modulation is only required if the data is being sent over a radio wave, or a laser beam. And even in the case of a laser, if you are content with on/off data streams, then there is no underlying signal to be modulated. Essentially all of the data whizzing round in your computer is doing so wit (MORE)

# Define modulation and modulation index?

a measure of the degree of frequency modulation expressed numerically for a pure tone modulation as the ratio of the frequency deviation to the frequency of the modulating signal.

# Why digital modulation is not enough for radio transmission and what are the general goals for digital modulation?

Worldwide regulation always uses FDM for separating different systems (TV, WLAN, radio, satellite â¦). Thus, all radio systems must modulate the digital signal onto a carrier frequency using analogue modulation. The most prominent system is the traditional radio: all music and voice use frequenc (MORE)

# Instructions for Fmd digital watch 193 or 058 module fmdco058 193 battery Cr2025 china module 100 ft resistant Plastic bezel 1005 stainless steel back?

Well you toss it in the trash and buy a real watch that a 10 year old kid did not put together 5,000 of them for 2 cents a day.

# What is modulation index for frequency modulation?

It varies depending on how strong you want the signal to come through on the receiving end.

# Why modulation is required in digital communication?

Need for modulation 1) to reduce the antenna height 2) to multiplex the more number of signals 3) to reduce the noise & distortions 4) to narrow banding the signal 5) to reduce equipment

# Are digital transmissions modulated over a carrier?

yes for transmission of the signal to take place smoothly,digital tranmission needs to be modulated over a carrier

# What is modulation and types of modulation?

Modulation may be defined as the process by which some characteristics of a signal called carrier is varied accordance with the instantaneous value of another signal called modulating signal. Types of Modulation: 1) Continuous Wave Modulation: ANALOG: AM, FM, PM DIGITAL : ASK, FSK, PSK 2) Pulse Modu (MORE)

# Why is AM modulation not an efficient way of modulation?

-- The power output stage in the transmitter must be operated either class A or class B. Whereas in FM the power output stage in the transmitter can operate class C which uses much less power per watt delivered to the antenna. -- For full modulation, audio power is required equal to 1 / 2 o (MORE)

# What is Modulation and what is the aim of modulation?

Modulation is any of several means of encoding an information carrying signal onto a carrier of fixed frequency. The purpose is to allow the information to be transported long distances.

# What is analog digital hybrid modulation?

ÂAnalog digital hybrid modulation seeks the ways to eliminate the incoherent quantization noise component in digital communication, instead of conveniently making it minimal..

# What are the technical characteristics of digital sensors that you should know to make your choice of digital modules PLC?

The technical characteristics of the digital sensors when makingyour choice of the digital modules PLC is that they should behighly sensible.

# What are the modules in Digital Marketing How it helpful to an Online Business?

Digital Marketing has good n.o of modules like SEO, SMO, GOOGLEADWORDS, AFFILIATE MARKETING, MOBILE MARKETING, APP MARKETING,E-MAIL MARKETING &so.on Each module has significance, SEO is optimizing the website &visible in SERP in an organic manner, Social Media Marketing (SMO& SMM) is targeting the a (MORE)