Pulse Code Modulation Example ITS323: Introduction to Data - - PowerPoint PPT Presentation

▶
pulse code modulation example
SMART_READER_LITE
LIVE PREVIEW

Pulse Code Modulation Example ITS323: Introduction to Data - - PowerPoint PPT Presentation

Nov 11, 2022 241 likes •466 views

ITS323/CSS331 PCM Example Pulse Code Modulation Example ITS323: Introduction to Data Communications CSS331: Fundamentals of Data Communications Sirindhorn International Institute of Technology Thammasat University Prepared by Steven Gordon on

slide-1
SLIDE 1

ITS323/CSS331 PCM Example

Pulse Code Modulation Example

ITS323: Introduction to Data Communications CSS331: Fundamentals of Data Communications

Sirindhorn International Institute of Technology Thammasat University

Prepared by Steven Gordon on 4 August 2015 ITS323Y15S1H08, Steve/Courses/2015/s1/its323/lectures/pulse-code-modulation-example.tex, r3926

slide-2
SLIDE 2

ITS323/CSS331 PCM Example

Input Analog Data

slide-3
SLIDE 3

ITS323/CSS331 PCM Example

Input Analog Data

4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-4
SLIDE 4

ITS323/CSS331 PCM Example

Case 1: 4ms Sampling Interval; 8 Levels

2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-5
SLIDE 5

ITS323/CSS331 PCM Example

Case 1: 4ms Sampling Interval; 8 Levels

001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-6
SLIDE 6

ITS323/CSS331 PCM Example

Case 1: 4ms Sampling Interval; 8 Levels

110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-7
SLIDE 7

ITS323/CSS331 PCM Example

Case 1: 4ms Sampling Interval; 8 Levels

010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-8
SLIDE 8

ITS323/CSS331 PCM Example

Case 1: Transmitting the Data

Transmitter Receiver

...010100110011100 Transmitted bits Input data Output data

What Data Rate Is Required?

◮ 1 sample every 4ms ◮ 3 bits per sample ◮ 3 bits per 4ms = 750 bps

slide-9
SLIDE 9

ITS323/CSS331 PCM Example

Case 1: Reproduced Data at Destination

010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-10
SLIDE 10

ITS323/CSS331 PCM Example

Case 1: Comparing Source and Destination Data

010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-11
SLIDE 11

ITS323/CSS331 PCM Example

Case 2: 2ms Sampling Interval; 8 Levels

010 001 100 011 110 010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-12
SLIDE 12

ITS323/CSS331 PCM Example

Case 2: Reproduced Data at Destination

010 001 100 011 110 010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-13
SLIDE 13

ITS323/CSS331 PCM Example

Case 2: Comparing Source and Destination Data

010 001 100 011 110 010 001 011 110 001 2 3 1 4 5 6 7 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-14
SLIDE 14

ITS323/CSS331 PCM Example

Case 3: 2ms Sampling Interval; 16 Levels

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-15
SLIDE 15

ITS323/CSS331 PCM Example

Case 3: Reproduced Data at Destination

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-16
SLIDE 16

ITS323/CSS331 PCM Example

Case 3: Comparing Source and Destination Data

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-17
SLIDE 17

ITS323/CSS331 PCM Example

Case 4: 1ms Sampling Interval; 16 Levels

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 0011 1001 1101 1000 0110 0100 0010 0011 0110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-18
SLIDE 18

ITS323/CSS331 PCM Example

Case 4: Reproduced Data at Destination

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 0011 1001 1101 1000 0110 0100 0010 0011 0110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-19
SLIDE 19

ITS323/CSS331 PCM Example

Case 4: Comparing Source and Destination Data

0101 0010 1000 0110 1100 0101 0011 0110 1100 0010 0011 1001 1101 1000 0110 0100 0010 0011 0110 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12

slide-20
SLIDE 20

ITS323/CSS331 PCM Example

Comparing All Cases

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 4 2 6 8 10 14 16 18 time [ms] amplitude 12 4 2 6 8 10 14 16 18 time [ms] amplitude 12

Case 2 Case 3 Case 1 Case 4

slide-21
SLIDE 21

ITS323/CSS331 PCM Example

Tradeoffs

Accuracy of Reproduced Data at Receiver

◮ Increasing sampling and/or levels; increased accuracy ◮ Case 4 is most accurate representation of original data ◮ Case 3 (and 2) are ok, Case 1 not so good

Transmission Data Rate Requirements

◮ Increasing sampling and/or levels; increased data rate

required to transmit bits

◮ Case 1: 750 b/s required ◮ Case 2: 1500 b/s required ◮ Case 3: 2000 b/s required ◮ Case 4: 4000 b/s required