Introduction to Fiber Optical Communications

Sailing HeZhejiang Universitysailing@zju.edu.cn

Tel: 0571-88206525

Website: http://coer.zju.edu.cn

Overview of the course (I)No. Date Teacher Content

1 22-Feb Sailing He Introduction & Optical Fibers

2 1-Mar Sailing He Overview & Introduction

3 8-Mar A. Ping Zhang Fiber Optics (1)

4 15-Mar A. Ping Zhang Fiber Optics (2)

5 22-Mar A. Ping Zhang Fiber Optics (3)

6 29-Mar A. Ping Zhang Fiber Optics (4)

7 12-Apr A. Ping Zhang Fiber Optics (5)

8 18-Apr A. Ping Zhang Fiber Optics (6) & Review

9 26-Apr Visiting prof. Invited Tutorial (Back-haul Transmission)

10 3-May YC Shi Optical Transmitters (1)

11 10-May YC Shi Optical Transmitters (2)

12 17-May Sailing He Passive Components (1)

13 24-May Sailing He Passive Components (2) & Prospectives

14 31-May YC Shi Receivers (1)

15 7-Jun YC Shi Receivers (2)

16 14-Jun Daru Chen Amplifiers

17 21-Jun A. Ping Zhang Review & Questions

Experiments• Testing of Optical Fibers

• NA, coupling, loss• Testing of Fiber Components

• Optical switching, isolator, attenuator• Optical Fiber Communication

• Data transmission, voice transmission• (similar techn =>) Optic-Fiber

Sensing Systems• Dual-beam interference, temperature

sensing, stress sensing

Overview (II)

What is photonics?• Old days: Optics

Then come out:

• electro-optics (optical devices with electrical effects; lasers, EO modulators/switches; popular in Japan)

• Optoelectronics (electronic devices involving light; LED, LCD, PD): general def for both electro-optics and Optoelectronics.

(combining optics and electronics)

• quantum optics,

• lightwave technology,... (IEEE J. Lightwave Techn.)

Now: ”photonics” covers all Analogy: Electronics <-- Photonics

• Generation of lightMaking the source of light having a specific wavelength or energy excluding natural light

• Control of lightAn area of industry which refracts, transmits, converges anddisperses the source of light according to its purpose

• Use of lightApplying and using the controlled light according to its application

Photonics Industry: all related industries of materials, parts, instruments and systems which make, control or apply the light.

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Photonics for Broadband Information Services

Broadband Information Services rely on• high-speed optical communications• high-capacity optical storage• high-resolution display

all with photonics as the key enabling technologies

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In the history of tele-communications, human communications services seem to evolve naturally

from low-speed services to high-speed services,

from narrow band services to broadband services,

from text/voice services to video/multimedia services,

from fixed-point services to mobile services

Ideally the final goal is

Anywhere, Anytime, Any format

Ubiquitous Broadband Communications Services

We are now right in the 21st century’s

“Broadband Transformation”

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5000 years of Human History

Tele-communications History40 years of Optical Fiber Comm.

(Corning, Bell Labs 1970-1)

~170 years of Telecom by Telegraph(Morse Code, 1837)

100+ years of Airflights(Wright Brothers, 1903)

50 years of Lasers and Photonics(Schawlow and Townes, Maiman 1960)

55 years of Transistors and Silicon Electronics ICs

(Shockley, Brittain, Bardeen, Bell Labs, 1947)80 years of Television

(Zworykin 1929)

2000 AD1000 AD2000 BC 1000 BC3000 BC 0

110 years of Wireless Radio Telecom(Marconi, 1901)

~130+ years of Telecom by Telephone(Bell, 1876)

Most Major Telecom Advances < 130 yrs since the invention of Telephone and

Wireless Radio

Photonics

• Q1: what is the origin of unit dB?

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1877: Bell Telephone Co.

1885:子公司 AT&T (for long distance phone services),21 yrs later bought mother company Bell Telephone Co.

1925: Bell Telephone Labs (BTL)

1927: First Trans-Atlantic Telephone Service (London and NY) Over Radio, Capacity 1 Call,Charge $75 For First 3 Minutes

1934: First Trans-Pacific (US and Japan), Over Radio, Capacity 1 Call, $39 For First 3 Minutes

1962: First Active Communications Satellite, Telstar Satellite

1977: First Optical Fiber Comm. System(Chicago) at 90 Mb/s

** AT&T Divestiture/breakup, 1984, 100 years later

1988: First Trans-Atlantic Undersea Optical Fiber Cable Telecom. System (280 Mb/s)

Invention of the First Telephone: Alexander Graham Bell (1876 )

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Fiber loss or optical amplifier gain in unit of dB (10 dB, 20 dB, etc.)

1969

1985

American Telephone and Telegraph

1885

2006

Divestiture

AT&T: created 7RBOC(Baby

Bells), Bellcore

4 RBOCs at&t, 2007Bellcore-> Lucent

Alcatel-Lucent 2007

SBC (Southwestern Bell Corp ) acquired AT&T 2005

AT&T: American Telephone and Television

The Broadband Transformation

From Narrowband to

Broadband

AT&T (Bell System)

1925: Bell (Telephone) Lab (R & D for AT & T and

Western Electric)

贝尔实验室[Bell (Telephone) Lab]自成立以来共推出27，000多项专利，现在平均每个工作日推出4项专利。在二三十年代，贝尔实验室的研究人员

推出了远距离电视传输和数字计算机。两项信息时代的重要发明-晶体管和信息论(Shannon Theory)都是贝尔实验室在40年代研究出来的。贝尔实验室在50和60年代的重大发明有太阳能电池，激光的理

论和通信卫星。

它是一个闻名世界的英才之地，是一个充满活力的创造和创新之源. 11位获诺贝尔科学奖，是世界上获得诺贝尔奖最多的研究机构。

The Nobel Prize in Physics 1937“for experimental discovery of the diffraction of electrons by crystals”

Clinton Joseph Davisson

(together with George Paget Thomson)

The Nobel Prize in Physics 1956"for their researches on semiconductors and their discovery of the transistor effect"

William Bradford Shockley John Bardeen

Walter Houser Brattain

The Nobel Prize in Physics 1977"for fundamental theoretical investigations of the electronic structure of magnetic and disordered systems"

Philip Warren Anderson(together with Sir Nevill Francis Mott and John Hasbrouck van Vleck)

2006: most innovative scientist in physics

The Nobel Prize in Physics 1978"for their discovery of cosmic microwave background radiation"

Arno Allan Penzias Robert Woodrow Wilson

The Nobel Prize in Physics 1997"for development of methods to cool and trap atoms with laser light"

Steven Chu

(together with with

Claude Cohen-Tannoudji

and William D. Phillips)

The Nobel Prize in Physics 1998“for their discovery of a new form of quantum fluid with fractionally charged excitations”

Robert B. Laughlin Horst L. Störmer

Daniel C. Tsui

Fiber Optics Windows

Optical fiber

Core diameter: 9 um

Comparison between the bandwidth of several communication modes

25THz

Rule of thumb for estimating bandwidth BW: About 10 percent of the frequency of the signal carrier.

copper wire: 1 MHz => BW ~100 kHz

coaxial cable: 100 MHz => BW ~ 10 MHz

microwave (incl satellite): 100 GHz => BW ~ 10 GHz

THz source:

fiber: 100-1000 THz => BW ~50 THzfiber：Minimal loss, Maximal bandwidth

Dr. Charles Kun Kao

Charles Gao’s Nobel Prize1966年，高锟在英国电气工程

师学会的学报（PIEE）上发表了一

篇 题 为 Dielectric-fibre surface waveguides for optical frequencies的论文，论文通过理论分析得出，只

要纯度足够高，光纤就可以用来长

距离传输信号。他计算出如何使光

在光导纤维中进行远距离传输，这

项成果最终促使光纤通信系统问世

，而正是光纤通信为当今互联网的

发展铺平了道路。随着第一个光纤

系统于1981年成功问世，高锟“光纤之父”美誉传遍世界。

Most of Major Advances in

Fiber Comm. Systems, Modern Optics, Lasers and Photonics Technologies within the last 40+ years

(out of ~ 5000 years of human history)

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Development of Digital Telecommunications

Bit Rate

Tb/sTb/s

Gb/sGb/s

Mb/sMb/s

Kb/sKb/s

18501850 19001900 2000200019501950 Year

Telegraph

Radio

Submarine Cable

Fiber OpticsFiber Optics

Advanced Fiber OpticsAdvanced Fiber Optics

Optical Fiber Communications 1970-2004, 30+ yearsCharles K. Kao, 1966

1960/70

1960

Laser

1970

Low-Loss Optical Fiber

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The Nobel Prize in Physics 1964

"for fundamental work in the field of quantum electronics, which has led to the construction of oscillators and amplifiers based on the maser-laser principle”

Laser Pioneers• Laser:

Light amplification by stimulated emission of radiationFirst demonstration of stimulated emission of electromagnetic waves by Charles Hard Townes, et al. in 1954. (maser: microwave amplification by stimulated emission of radiation); predicted theoretically in 1958 “Laser”(light amplification by stimulated emission of radiation) .

Charles Hard Townes(in Bell Lab during 1933-47, later to Columbia Univ)

Nicolay Gennadiyevich Basov

Aleksandr Mikhailovich Prokhorov

Experimental demonstration of first laser: Theodore H. Maiman (Hughes Res. Lab), 1960

(“LASER” was first used in Gordon Gould's famous notebook together with the FP cavity in 1957, 3 months before Townes)

Q2: draw a fig to show the principle of a laser

Bell Labs, MHNew Jersey, USA1971

Solid state (semiconductor) laser and current injection pumping

Semiconductor Diode Laser, turned out to be the most useful laser in photonic information systems (Optical Fiber Communication Systems, CDs, DVDs, Laser Printers,, Optical Sensors, etc.).

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Integrated DFB Laser / EA Modulator

DFB LaserSection

EA ModulatorSection

n-InP Substrate

InGaAsPGrating

Fe:InPBlocking

p-InGaAs/InP Cap

Selective-AreaMOCVD Grown MQW-SCH

HR

(Bell Labs 1980’s)

Moore’s Law for photonic lightwave circuits

Ultra-compact, high integration density, large-scale monolithic integration