Home / Electronics Articles / Advantages, disadvantages and There are some disadvantages of PCM (pulse code modulation) which are given below, Difference between PCM and DPCM ยท Difference between pulse. Answer to Briefly describe an advantage and a disadvantage of using differential pulse code modulation (DPCM) over pulse code modu. This page covers advantages and disadvantages of mentions PCM Also refer advantages and disadvantages of DPCM >> and ADPCM >> techniques.

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For a sample to be reproduced accurately in a PCM receiver, each cycle of the analog input signal fa must be sampled at least twice.

Advantages of PCM | disadvantages of PCM

But, at any sampling rate two types of distortion limits performance of DM encoder. The higher the amplitude of the sample, the farther to the right the pulse is positioned within the prescribed time slot.

Mathematically, the minimum Nyquist sampling rate is: The output signal contains information about sign of signal change for one level comparing to previous time interval. Another example would be an audio signal with a low-biased frequency spectrum. So, output signal contains bipolar pulses. Code number is in the form of binary representation.

Difference between PCM and DPCM

PCM is a binary system where a pulse or lack of a pulse within a prescribed time slot represents either a logic 1 or a logic 0 condition. In general, if M numbers 0,1, Histogram of PCM sampled image Fig 5.

Following are the benefits or advantages of PCM: With conventional PCM, each code is a binary representation of both the sign and dsiadvantage magnitude of a particular sample.


It is important to point out that in forming a prediction reciever i. Slope overload distorsion – is caused by use of step size delta which is too small to follow portions of waveform that has a steep slope.

For illustration, we present two histograms made from the same picture which were coded in two ways.

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The rounded off error is called the called the quantization error Qe. Images and video signals are examples of signal which have cpcm mentioned correlation.

DPCM compression depends on the prediction technique, well-conducted prediction techniques advantabe to good compression rates, in other cases DPCM could mean expansion comparing to regular PCM encoding. DPCM compression of images and video signals DPCM conducted on signals with correlation between successive samples leads to good compression ratios.

The digits of binary representation of the code number are transmitted as pulses. It can be reduced by decreasing the step size. The magnitude of a quantum is also called the resolution.

Therefore, as shown in the figure, each sample voltage is rounded off quantized to the closest available level and then converted to its corresponding PCM code. D elta m odulation DM is a subclass of differential pulse code modulation.

The amplitude of a pulse coincides with the amplitude of the analog signal. The four predominant methods of pulse modulation: We think you have liked this presentation.


Hence using PCM, continuous amplitude and continuous time signal waveform is converted into discrete amplitude and discrete time waveform.

Auth with social network: The highest amplitude sample produces a pulse to the far right, and the lowest amplitude sample produces a pulse to the far left. Quantizer generates output according to difference signal if difference signal is positive quantizer generates positive impulse, and if the difference is negative quantizer generates negative signal. Differential pulse code modulation DPCM is designed specifically to take advantage of the sample-to-sample redundancies in typical speech waveforms.


In practice, DPCM is usually used with lossy compression techniques, like coarser quantization of differences can be used, which leads to shorter code words. To make this website work, we log user data and share it with processors.

Advantages, disadvantages and application of PCM (pulse code modulation)

This page covers advantages and disadvantages of PCM. As it can be noticed in DM there is a feedback by which the output signal is brought to the integrator which integrates and the bipolar pulses forming a pulse signal which disdavantage being compared to the input value.

In PCM, we represent each quantized level by a code number and later transmit the code number rather than sample value itself. It has been shown that under the mean-squared error optimization criterion, apart constructions of quantizatior and predictor are good approximations of joint optimization.

Distinguish between data and signals, and.

The digital code is stored fpcm the memory and which is later re-called for the playback. Published by Elijah Jenkins Modified over 3 years ago.

DM encoder Input signal is compared to the integrated output and delta signal difference between the input signal and the pulse cpcm is brought to quantizer.