Explain pulse-code modulation, Electrical Engineering

Assignment Help:

Q. Explain Pulse-Code Modulation?

PCM is the simplest and oldest waveform coding scheme for processing an analog signal by sampling, quantizing, and binary encoding. Figure shows a functional block diagram of a PCM system transmitter. In order to guarantee that the message is band-limited to the spectral extent for which the system is designed, a low-pass filter is introduced. The compressor is rather optional for better performance. Let us assume that the PCM signal is transmitted directly over the baseband channel. Corrupted by the noise generated within the receiver, the PCM signal is shown as the input to the PCM reconstruction function in Figure, which depicts a block diagram of functions (including an optional expandor) needed to receive PCM. The operations of the receiver are basically the inverse of those in the transmitter. The first andmost critical receiver operation is to reconstruct the originally transmitted PCM signal as nearly as possible from the noise-contaminated received waveform. The effect of noise is to be minimized through a careful selection of circuit implementation.

891_Explain Pulse-Code Modulation.png

The only knowledge required of the receiver to reconstruct the original PCMsignal iswhether the various transmitted bits are 0s and 1s, depending on the voltage levels transmitted, assuming that the receiver is synchronized with the transmitter. The two levels associated with unipolar pulses of amplitude A are 0 and A, whereas those associated with polar pulses (of amplitudes ±A) are A and -A. It is, of course, better for the receiver if the ratio of the pulse-caused voltage to the noise rms voltage is the largest possible at the time of measurement. Figure shows PCM reconstruction circuits for unipolar, polar, and Manchester waveforms.


Related Discussions:- Explain pulse-code modulation

Rectifiers - Rectifiers and inverters , Rectifiers As discussed  above...

Rectifiers As discussed  above the  purpose  of the  rectifier is to  convert the incoming  ac from a transformer or other ac  source  to some  form of  pulsating dc. That it i

What is transient program area, What is TPA (transient program area)? T...

What is TPA (transient program area)? The memory system is divided in three major parts: transient program area, System is and XMS that is extended memory system.

Show capital asset pricing model, Q. Show Capital asset pricing model? ...

Q. Show Capital asset pricing model? This model was developed by the William F Sharpe ( 1990 Nobel prize winner in the economy ) and john linter in 1960. The model attempt to c

power system operation, AskWrite short notes on pit head generation. ques...

AskWrite short notes on pit head generation. question #Minimum 100 words accepted#

Show the procedure of hex to decimal conversion, Q. Show the procedure of H...

Q. Show the procedure of Hex to Decimal Conversion? To convert from the Hex to the Decimal, multiply the value in each position by its hex weight and add each value. Using the

Substation preventive maintenance scheduling optimization, Introduction: ...

Introduction: The scheduling system that is followed by the maintenance department is not well established and is dependable on employee's personal judgment. There were a lot o

Give the operating modes of 8259a, Give the operating modes of 8259a? (...

Give the operating modes of 8259a? (a) Automatic Rotation (b) End of Interrupt (EOI) (c) Fully Nested Mode  (d) Automatic EOI Mode (e) Specific Rotation (f) Edge

Define stability - characteristics of discrete time systems, Define Stabili...

Define Stability - Characteristics of Discrete Time Systems? The LTI system is stable if its impulse response satisfies the condition This condition is satisfie

Transients in r-l-c circuits, Transients in R-L-C circuits: Scenario ...

Transients in R-L-C circuits: Scenario The Laplace transform is a valuable mathematical tool which allows the solution of difficult differential equations to be easily de

Sketch the asymptotic bode diagrams, Q. Sketch the asymptotic Bode diagrams...

Q. Sketch the asymptotic Bode diagrams for the following functions:

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd