No, PCM is simply a digital representation of an analog signal. The actual analog to digital conversion is done by an analog-to-digital converter.
PCM technique is used to convert analog voice signals into digital. In PCM the analog frequency is first sampled and then converted into binary bits. Each samples are taken as 8bits long. Basic communication theory requires that a minimum sampling rate of twice the frequency of the signal to be sampled will result in an accurate representation of the original signal.Human voice can have max 4000hz frequency, therefore sampling rate should be 8000 samples/sec.Which implies required bit rate for transmitting voice is 8000*8 = 64000 bits/sec = 64kbps.
PCM is preferable because of better SNR characteristics.
ADVANTAGES-Low Noise Susceptibility-Repeatability-Storage-Encoded SignalDISADVANTAGES-PCM requires very complex encoding and quantizing circuitry.-PCM requires a large bandwidth compared to analog signals.
Hi,1) Digital signals do not get corrupted by noise etc. You are sending a series of numbers that represent the signal of interest (i.e. audio, video etc.)2) Digital signals typically use less bandwidth. This is just another way to say you can cram more information (audio, video) into the same space.3) Digital can be encrypted so that only the intended receiver can decode it (like pay per view video, secure telephone etc.)There are others, but this is three of the biggies.Hi!Following are the Advantages of Digital Transmission over analog transmission.1. The signal is exact. For example, Digital formats like PCM (Pulse Code Modulation) can hold the exact digital format of sounds.2. Digital signals can checked for errors. Generally, all digital transmission methods use 'head labels' to provide better checking facilities. Head label may contain how many packets may need to complete the transmission, what is the sequence number of each packet of data, acknowledgment labels etc.3. A variety of services can afford over one line. For example, IpTV connection can used to watch cable TV channels while browsing the Internet through a PC using same line. This line can also used to make a phone call at the same time.4. Digital data can be compressed and therefore possible to pass over higher bandwidths. Any digital data; data, image, video, voice can be compressed.5. More secure. Digital data can be encrypt using an encryption method. Only the dedicated receiver can decode the message.6. Supports data integrity. Simple to integrate voice, video and data. Digital transmission provides easier way to integrate different digital formats.7. Digital transmission provides higher maximum transmission rates via medium such as optical fibers. Typically, digital transmissions use less bandwidth.Hope this will help you!(H.W Thushara Indika from Bandarawela - Sri Lanka)
telkom system, CD laser disks, digital audio recording, digitized video special effects, voice mail, digital video. It is also widely used in Radio Control Units. Radio transmitter and receiver for remote controlled cars, planes, boats etc. Often abbreviated with PCM in these. A pulse code modulated radiosignal is more resistant to interference than a normal "old-fashioned" signal.
No, Pulse Code Modulation is a communication method used to carry digital data but is not part of any analog to digital conversion. PCM is often used to carry audio data as a digital stream and therefore is the encoding used as the signal is first converted to a digital format.
A digital signal is a physical signal that is a representation of a sequence of discrete values (a quantified discrete-time signal), for example of an arbitrary bit stream, or of a digitized (sampled and analog-to-digital converted) analog signal. The term digital signal can refer to either of the following:any continuous-time waveform signal used in digital communication, representing a bit stream or other sequence of discrete valuesa pulse train signal that switches between a discrete number of voltage levels or levels of light intensity, also known as a line coded signal or baseband transmission, for example a signal found in digital electronics or in serial communications, or a pulse code modulation (PCM) representation of a digitized analog signal.A signal that is generated by means of a digital modulation method (digital passband transmission), to be transferred between modems, is in the first case considered as a digital signal, and in the second case as converted to an analog signal.
A phonograph turntable that is used to convert tracks on vinyl records into a digital format such as CD audio or MP3. With a built-in phono preamp and analog-to-digital converter, the USB turntable converts the cartridge's analog signal to digital PCM and sends it to the computer via USB. Software in the computer converts the PCM into the required format.
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 Modulation : ANALOG: PAM, PDM, PPM DIGITAL : PCM
Quantization noise is a model of quantization error introduced by quantization in the analog-to-digital conversion(ADC) in telecommunication systems and signal processing.
PCM technique is used to convert analog voice signals into digital. In PCM the analog frequency is first sampled and then converted into binary bits. Each samples are taken as 8bits long. Basic communication theory requires that a minimum sampling rate of twice the frequency of the signal to be sampled will result in an accurate representation of the original signal.Human voice can have max 4000hz frequency, therefore sampling rate should be 8000 samples/sec.Which implies required bit rate for transmitting voice is 8000*8 = 64000 bits/sec = 64kbps.
PCM is preferable because of better SNR characteristics.
In telecommunications it means Pulse Code Modulation, which is a digital means of sending a signal from point A to point B.
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 respectively. Examples of Digital PM are PCM and PDM i.e pulse code and pulse delta modulations respectively.
Pulse-code modulation (PCM) is a method used to digitally represent analog signals.
When you push the button in, a signal is sent to the PCM to "block" overdrive.When you push the button in, a signal is sent to the PCM to "block" overdrive.
comparing between pcm system and analog system : power , B.W , SNR , transmission length ?