DCOM PRCATICAL-DELTA MODULATION


                                                                                     

 Name of Experiment :- Experimental study of Delta Modulation and signal reconstruction


The sampling rate of a signal should be higher than the Nyquist rate, to achieve better sampling. If this sampling interval in Differential PCM is reduced considerably, the sampleto-sample amplitude difference is very small, as if the difference is 1-bit quantization, then the step-size will be very small i.e., Δ delta.

Delta Modulation

The type of modulation, where the sampling rate is much higher and in which the stepsize after quantization is of a smaller value Δ, such a modulation is termed as delta modulation.

Delta Modulator

The Delta Modulator comprises of a 1-bit quantizer and a delay circuit along with two summer circuits. Following is the block diagram of a delta modulator.

Delta Modulator

The predictor circuit in DPCM is replaced by a simple delay circuit in DM.

From the above diagram, we have the notations as −

  • x(nTs) = over sampled input

  • ep(nTs) = summer output and quantizer input

  • eq(nTs) = quantizer output = v(nTs)

  • x^(nTs) = output of delay circuit

  • u(nTs) = input of delay circuit


 
           PRE TEST 

                                                                      THEORY                         PRACTICAL


 
                                                                                                                                                POST TEST


Reference:- 














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