Difference between Delta Modulation (DM) and Differential Pulse Code Modulation (DPCM)
Delta Modulation (DM):
Delta modulation is associate analog to digital and digital to analog signal conversion technique. Delta modulation is utilized to appreciate high signal to noise magnitude relation. It uses one bit PCM code to appreciate digital transmission of analog signal. With delta modulation, rather than transmit a coded illustration of a sample only one bit is transmitted, that simply indicates whether or not or not the sample is larger or smaller than the previous sample. it’s the most effective kind or simplest sort of Differential Pulse Code Modulation. Delta modulation signal is smaller than Pulse Code Modulation system.
Differential Pulse Code Modulation (DPCM):
DPCM stands for Differential Pulse Code Modulation, is same as Pulse Code Modulation technique used for reworking analog signal into digital signal. Differential Pulse Code Modulation has moderate signal to noise magnitude relation. Differential Pulse Code Modulation differs from Pulse Code Modulation as a results of it quantizes the excellence of the actual sample and expected value. that’s the reason it’s cited as as differential Pulse Code Modulation(DPCM).
DPCM transmitter and DPCM receiver operations are given below through figure:
In the above diagram, if the signal is large then the next bit in digital data is 1 otherwise next bit is 0.
Let’s see that the difference between DM and DPCM, which are given below:
|S.NO||Comparison based on||DM||DPCM|
|1.||Feedback||In DM, feedback exists in transmitter.||Here, feedback exists in both transmitter and receiver.|
|2.||signal to noise ratio||DM has poor signal to noise ratio.||DPCM has fair signal to noise ratio.|
|3.||Transmission bandwidth||It requires lowest bandwidth.||Here, DPCM requires less bandwidth than PCM.|
|4.||Levels, step size||In DM, step size is fixed.||While here, number of levels are fixed.|
|5.||Efficiency||DM is less efficient than DPCM.||DPCM is more efficient.|
|6.||Number of bits ||In DM, only one bit is used per sample.||Here more than one but less than PCM(Pulse Code Modulation) bits are used.|
|7.||Quantization error and distortion||Slope overload distortion and granular noise are present.||Slope overload distortion and quantization noise are present.|
|8.||Applications||It is generally used in speeches and images.||It is mostly used in videos and speeches.|