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CPET/ECET 355. 6. Multiplexing Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne www.ecet.ipfw.edu/~lin. Multiplexing. FDM – Frequency Division Multiplexing
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CPET/ECET 355 6. Multiplexing Data Communications and Networking Fall 2004 Professor Paul I-Hai Lin Electrical and Computer Engineering Technology Indiana University-Purdue University Fort Wayne www.ecet.ipfw.edu/~lin 6. Multiplexing - Lin
Multiplexing • FDM – Frequency Division Multiplexing • WDM – Wave Division Multiplexing • TDM – Time Division Multiplexing 6. Multiplexing - Lin
Multiplexing From p. 149, Figure 6.1 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Multiplexing • Categories of Multiplexing From p. 150, Figure 6.2 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
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 6. Multiplexing - Lin
Frequency Division Multiplexing • Multiplexing Process • Demultiplexing Process From p. 151, Figure 6.4 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Frequency Division Multiplexing • Demultiplexing Process From p. 152, Figure 6.5 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
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. 6. Multiplexing - Lin
Frequency Division Multiplexing • Example 6-1: Solution From p. 152, Figure 6.6 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
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 6. Multiplexing - Lin
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 6. Multiplexing - Lin
Frequency Division Multiplexing • Analog Hierarchy From p. 154, Figure 6.9 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Wave Division Multiplexing • WDM – light signals From p. 156, Figure 6.10 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Wave Division Multiplexing • WDM – Combining/Splitting From p. 156, Figure 6.11 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Time Division Multiplexing • TDM – Digital data • Time Slots and Frames From p. 157, Figure 6.12 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Time Division Multiplexing • Interleaving From p. 159, Figure 6.14 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
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 • Before Multiplexing data rate = 1 Kbps T = 1/Data rate = 1ms • Link – Data rate = 4 x 1 Kbps = 4 Kbps 6. Multiplexing - Lin
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 • One time slot = 1/(Link data rate) = 1/4Kbps = 250 μs • One frame = 4 time slots = 1 ms 6. Multiplexing - Lin
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 6. Multiplexing - Lin
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 6. Multiplexing - Lin
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 6. Multiplexing - Lin
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 6. Multiplexing - Lin
Time Division Multiplexing • Digital Signal (DS) Service From p. 162, Figure 6.18 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Time Division Multiplexing • T Lines From p. 163, Table 6.1 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Time Division Multiplexing • The T1 Frames From p. 164 Fig. 6.19 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Time Division Multiplexing • The T1 Frame Structure • 8000 Frames/sec x 193bps for a frame = 1.544 Mbps From p. 164 Fig. 6.19 of Data Communications and Networking, Forouzan, McGrawHill 6. Multiplexing - Lin
Summary Questions? 6. Multiplexing - Lin