10/3/ Multiplexing - Lin 1 CPET/ECET Multiplexing Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne

10/3/ Multiplexing - Lin 2 Multiplexing 1. FDM – Frequency Division Multiplexing 2. WDM – Wave Division Multiplexing 3. TDM – Time Division Multiplexing

10/3/ Multiplexing - Lin 3 Multiplexing From p. 149, Figure 6.1 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 4 Multiplexing Categories of Multiplexing From p. 150, Figure 6.2 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 5 Frequency Division Multiplexing FDM Definition – Carrier frequencies, Guard bands, Analog signals Multiplexing Process Demultiplexing Process From p. 151, Figure 6.3 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 6 Frequency Division Multiplexing Multiplexing Process Demultiplexing Process From p. 151, Figure 6.4 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 7 Frequency Division Multiplexing Demultiplexing Process From p. 152, Figure 6.5 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 8 Frequency Division Multiplexing Example 6-1 Assume that a voice channel occupies a bandwidth of 4 KHz. We need to combine three voice channels into a link with a bandwidth of 12 KHz, from 20 to 32 KHz. Show the configuration using the frequency domain without the use of guard bands.

10/3/ Multiplexing - Lin 9 Frequency Division Multiplexing Example 6-1: Solution From p. 152, Figure 6.6 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 10 Frequency Division Multiplexing Example 6-2: Five channels, each with a 100- KHz bandwidth, are to be multiplexed together. What is the minimum bandwidth of the link if there is a need for a guard band of 10 KHz between the channels to prevent interference From p. 153, Figure 6.7 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 11 Frequency Division Multiplexing Example 6-3: Four data channels (digital), each transmitting at 1 Mbps, use a satellite channel of 1 MHz. Design an appropriate configuration using FDM From p. 154, Figure 6.8 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 12 Frequency Division Multiplexing Analog Hierarchy From p. 154, Figure 6.9 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 13 Wave Division Multiplexing WDM – light signals From p. 156, Figure 6.10 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 14 Wave Division Multiplexing WDM – Combining/Splitting From p. 156, Figure 6.11 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 15 Time Division Multiplexing TDM – Digital data Time Slots and Frames From p. 157, Figure 6.12 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 16 Time Division Multiplexing Interleaving From p. 159, Figure 6.14 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 17 Time Division Multiplexing Example 5. Four 1-Kbps connections are multiplexed together. A unit is 1 bit. Find (1) the duration of 1 bit before multiplexing, (2) the transmission rate of the link, (3) the duration of a time slot, and (4) the duration of a frame? Solution 1. Before Multiplexing data rate = 1 Kbps T = 1/Data rate = 1ms 2. Link – Data rate = 4 x 1 Kbps = 4 Kbps

10/3/ Multiplexing - Lin 18 Time Division Multiplexing Example 5. Four 1-Kbps connections are multiplexed together. A unit is 1 bit. Find (1) the duration of 1 bit before multiplexing, (2) the transmission rate of the link, (3) the duration of a time slot, and (4) the duration of a frame? Solution 3. One time slot = 1/(Link data rate) = 1/4Kbps = 250 μs 4. One frame = 4 time slots = 1 ms

10/3/ Multiplexing - Lin 19 Time Division Multiplexing Example 6: Four channels are multiplexed using TDM. If each channel sends 100 bytes/s and we multiplex 1 byte per channel: Show the frame traveling on the link The size of the frame (4 bytes or 32-bits) From p. 159, Figure 6.14 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 20 Time Division Multiplexing Example 6: Solution 4 Channels, each channel – 100 bytes/sec 1 Frame = 4 bytes Frame rate = 100 Frames/sec Frame duration = 1/frame rate = 0.01 sec Link bit rate = 100 Frames x 4 bytes/Frame x 8-bit/byte = 3200 bps The duration of a frame – 0.01 sec The frame rate – 100 Frames/sec The bit rate for the link – 3200 bps

10/3/ Multiplexing - Lin 21 Time Division Multiplexing Example 7: A multiplexer combines four 100- Kbps channels using a time slot of 2 bits. Show the output with four arbitrary inputs. What is the frame rate? What is the frame duration? What is the bit rate? What is the bit duration? From p. 160, Figure 6.16 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 22 Time Division Multiplexing Synchronization: –Mutiplexing/Demultiplexing –Framing bits Bit Padding –Handling signals with different data rates From p. 160, Figure 6.17 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 23 Time Division Multiplexing Digital Signal (DS) Service From p. 162, Figure 6.18 of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 24 Time Division Multiplexing T Lines From p. 163, Table 6.1 of Data Communications and Networking, Forouzan, McGrawHill ServiceLine Rate (Mbps) Voice Channels DS-1T DS-2 DS-2T DS-3 DS-3T DS-4T

10/3/ Multiplexing - Lin 25 Time Division Multiplexing The T1 Frames From p. 164 Fig of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 26 Time Division Multiplexing The T1 Frame Structure –8000 Frames/sec x 193bps for a frame = Mbps From p. 164 Fig of Data Communications and Networking, Forouzan, McGrawHill

10/3/ Multiplexing - Lin 27 Summary Questions?