›
›

Bài giảng Computer Networks 1 (Mạng máy tính 1) - Lecture 2: Communication Media - Phạm Trần Vũ

Download
Computer Networks 1  
(Mạng Máy Tính 1)  
Lectured by: Dr. Phạm Trần Vũ  
Lecture 2: Communication Media  
Reference:  
Chapter 2 - “Computer Networks”,  
Andrew S. Tanenbaum, 4th Edition, Prentice Hall, 2003.  
Content  
ꢀ Theoretical basis for data communication  
ꢀ Guided transmission media  
ꢀ Wireless transmission  
ꢀ Digital subscriber lines  
ꢀ Internet over TV cables  
3
The Theoretical Basis for Data  
Communication  
•
•
•
•
Fourier Analysis  
Bandwidth  
Bandwidth-Limited Signals  
Maximum Data Rate of a Channel  
4
Fourier Series  
5
Bandwidth  
ꢀ
ꢀ
Signals lose power during transmission  
Different transmission facilities diminish different  
Fourier components with different amounts ->  
distortion of signals  
ꢀ
ꢀ
Usually, high frequency components will be  
diminished  
Bandwidthn be  
transmitted without being strongly attenuated  
6
Bandwidth-Limited Signals (1)  
A binary signal and its root-mean-square Fourier amplitudes.  
(b) – (c) Successive approximations to the original signal.  
7
Bandwidth-Limited Signals (2)  
(d) – (e) Successive approximations to  
the original signal.  
8
Bandwidth-Limited Signals (3)  
Relation between data rate and harmonics for a voice  
telephone line  
9
Guided Transmission Data  
•
•
•
Twisted Pair  
Coaxial Cable  
Fiber Optics  
10  
Twisted Pair  
(a) Category 3 UTP.  
(b) Category 5 UTP.  
11  
Coaxial Cable  
A coaxial cable.  
12  
Fiber Optics  
(a) Three examples of a light ray from inside a silica fiber  
impinging on the air/silica boundary at different angles.  
(b) Light trapped by total internal reflection.  
13  
Transmission of Light through  
Fiber  
Attenuation of light through fiber in the infrared region.  
14  
Fiber Cables  
(a) Side view of a single fiber.  
(b) End view of a sheath with three fibers.  
15  
Fiber Optic Networks  
A fiber optic ring with active repeaters.  
16  
Fiber Optic Networks (2)  
A passive star connection in a fiber optics network.  
17  
Wireless Transmission  
• The Electromagnetic Spectrum  
• Radio Transmission  
• Microwave
• Infrared and Millimeter Waves  
• Lightwave Transmission  
18  
The Electromagnetic Spectrum  
The electromagnetic spectrum and its uses for  
communication.  
19  
Radio Transmission  
(a) In the VLF, LF, and MF bands, radio waves follow the  
curvature of t
(b) In the HF band, they bounce off the ionosphere.  
20  
Tải về để xem bản đầy đủ
pdf 32 trang yennguyen 15600 Free
Download
Bạn đang xem 20 trang mẫu của tài liệu "Bài giảng Computer Networks 1 (Mạng máy tính 1) - Lecture 2: Communication Media - Phạm Trần Vũ", để tải tài liệu gốc về máy hãy click vào nút Download ở trên

File đính kèm:

  • pdfbai_giang_computer_networks_1_mang_may_tinh_1_lecture_2_comm.pdf