0
AM = Amplitude Modulation and is more prone to noise because the signal amplitude caries the intellegence, Noise
changes this easily.
PWM is Pulse Width Modulation and noise does not change the width of the pulses, though it may introduce other
pulses. Therefore the original intellegence is still recoverable.
Wiki User
∙ 10y ago
Add your answer:
Earn +20 pts
What is noise filter?
noise filters are used in electronics and electric curcuts to reduce the the noise level which the electric switching generats sometimes the are single phase and there are three phase also the most used noise filters are ssr emc filters
What are the applications of Butterworth filters?
especially it is very much useful in high quality AUDIO applications because of its flat response in both pass band and stop band where as chebyshev will be useful in signal monitoring applications where the phase is not important criterialow pass filters are used to filter noise from a circuit .noise is a high freequncy signal, when passed through a low pass filter most of the noise is removed and aclear sound is produced
Why you need modulation?
It might be helpful to have a working definition of modulation before making a statement as to why it is needed. In fact, with an understanding of what modulation is, it will be obvious why it is included in electronic communications.Modulation is the "message" or the "intelligence" that is impressed on a radio frequency (RF) carrier. When we transmit a signal, we generate a carrier frequency, and then we modulate it. We "add" the message or the information we wish to transmit by modulating the carrier in some way. There are at least a dozen different modulation schemes ranging from simple to real head scratchers. They either modify the amplitude, the frequency or the phase of the carrier. Let's look at a few.The simplest modulation technique is taking the transmitted signal and turning it on and off. It is "keyed" to send a series of pulses. Morse code uses on-off keying. In this method of modulation, no modification of the RF carrier signal itself is made. It is simply switched on and off. (It could be looked at as amplitude modulation with the carrier either at zero amplitude or at "maximum" amplitude with nothing in between.) A series of pulses can be transmitted. With Morse code, a short "on" period will send a dot or "dit" out. If we extend the "on" period a bit, we can send a dash or "dah" out. Nothing real sophisticated here, but basic and effective communication. There are obvious limits to how fast information can be transmitted with this modulation scheme. (But don't tell the hams who still use it!)Most of us are familiar with AM radio. AM is amplitude modulation. The amplitude of the RF carrier is modified to modulate it. The amplitude of the modulating signal will determine the amount that the amplitude of the carrier is changed. (The volume of the modulation determines how much the amplitude of the carrier is changed. The frequency of the modulating signal determines the rate of change of the amplitude of the carrier. (The frequency of the modulation determines how fast the amplitude of the carrier is changed.). The frequency of the carrier is held constant through all this.How about FM? In frequency modulation, the amplitude of the carrier is constant. It's left alone. But the frequency of the RF carrier is changed. It is swung above and below where it sits (it's assigned center frequency) at a rate proportional to the frequency of the modulating signal, and at an amount proportional to the amplitude of the modulating signal. In FM single sideband, the carrier frequency and the frequencies above the carrier are transmitted and the frequencies below the carrier are suppressed (upper sideband transmission). Or the frequencies below the carrier are transmitted with the carrier and the upper frequencies are suppressed (lower sideband transmission). In conventional television, the video signal is single sideband, suppressed carrier. It's like "regular" upper sideband transmission except the carrier signal is suppressed. Sideband transmission "saves" space on the RF spectrum. And it works because we really don't need "all" of the FM signal to demodulate the signal at the receiver.Other forms of modulation become more complex. CDMA (code division multiple access), TDMA (time division multiple access) and other methods are used in cell phones to modulate the carrier so the digital data stream can be impressed on the carrier.Modulation is the addition of intelligence to a carrier signal. It's the message. Modulation is necessary because the point of communication is getting the message through.A Simple answer:Simply this... Any communications medium: e.g. Free space - radio waves, Air - Sound waves or radio waves, Optical Fibre - Light, Copper Wires Electrical Anergy (with frequency limits of the copper wire construction) is made for a certain type of signal. But if the signal we want to send is not compatible with the medium, then it does not travel well.Modulation changes the information we want to send from it's original form, into one that is more compatable with the medium we are trying to use.For example, your computer speaks digital over a TCP/IP LAN which requires CAT 5 or better rated cables,, but to connect to your internet service provider (ISP), you need to send the signal over the wires of the telephone company (made for voice tones). To make this connection, and ADSL modem (modulator/demodulator) is used to convert the data into audio tones, which pass over the telephone line, and at the far end are converted back to digital to join the service providers network. in the reverse direct the ISP does the same, and the signals are de-modulated, back to data for your network.Or in simple terms, Its about best use of the medium. Everything else is just a away of doing it. And there are a lot of possible ways to choose.
Why FSk is good choice for low speed modem?
FSK is not always used for high-speed data communications, since it is far less efficient in both power and bandwidth than most other modulation modes. In addition to its simplicity, however, FSK has the advantage that encoded signals will pass through AC-coupled links, including most equipment originally designed to carry music or speech.
What is digital tachometer?
A: It is like an analog tachometer it reads RPM or speed and display in Numbers on a read out. You can find the application on airplanes and your car except it is an analogue instrument. I built one once for my car the read the RPM it was totally unsatisfactory because of the car inherited noise and on a 3 digit readout the least significant number was totally useless. The noise It can be clean out with filters then again the read out will be slow but on a car where the speed changes continuously analogue is proven Superior and most people don't care it it is 100 RPM or 101
Why is that amplitude modulation is mostly affected by man made interference than frequency modulation?
since man made devices always produce noise for other electronic devices and noise always add at the amplitudes of any wave.in the am,amplitude is varying w.r.t. the information or modulating signal so it is most prone to noise and hence affected most by man made devices
What is difference between ask and am?
The most fundamental difference, I would say, is that Amplitude Modulation (AM) is a kind of Analog Modulation Technique (the modulation is applied continuously in response to the analog information signal) where Amplitude Shift Keying is a type of Digital Modulation Technique ( an analog carrier signal is modulated by a discrete signal, 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).
Which cellular system uses the most bandwidth efficient modulation?
I think it is Frequency Modulation with Phase modulation which it the most bandwidth efficient
The most flood prone state of India?
Assam is the most flood prone state.
Why frequency modulation is preffered over AM?
-- FM is better for the person on the transmitting end, because it's easier and cheaper to generate with high quality. Modulation can be applied in an early stage of the transmitter, at low frequency, low power, and with a small modulation index, and the final signal for transmission can be derived by frequency multiplication and power amplification, without garfing up (corrupting) the signal and producing a lot of intermod. AM must be modulated at the final frequency and power, which requires half as much audio power as final carrier output power, which is expensive. -- FM is better for the person on the receiving end, because most of the radio noise in nature, as well as man-made radio noise, is amplitude noise. If your receiver doesn't care about changes in amplitude, it's immune to a lot of the noise that gets picked up on the way from the transmitter to the receiver.
What is the most popular technique?
what is the most popular army rehersal technique
What months is Oklahoma most prone to tornadoes?
Oklahoma is most prone to tornadoes in the months of April, May, and June.
What is the most popular rehearsel technique?
what is the most popular army rehersal technique
Which are the three forms of modulation?
There are actually 4 forms. The first and most common is AM, the next is SSB or Single Side band, the third is FM (Frequency Modulation) and the fourth is Digital
What is the main use of frequency modulation?
Frequency modulation is used to broadcast radio waves to receivers. The most common use of it is in FM radio, which contains a range of radio frequencies.
Is Washington earthquake prone?
it is prone. In fact it is in the top five most quake states. So yeah it is prone to earthquakes. by Abbigail
What is a disadvantage of living on flat land?
Its a flood prone area
