Specification :

I. Introduction
ZY11804I Optical Fiber Communication Principle Experiment System is the newly designed multi-functional, cost-effective kit aimed to meet the theory teaching requirement of " Optical Fiber Communication Principle" . It closely keeps to " Optical Fiber Communications Principle" course syllabus, with rich experiment contents, which fully meet the experiment teaching needs of fiber-optic communication course, as well as the course design, graduation design, and secondary development by using large-scale FPGA. The experiment kit is suitable for various types of optical fiber communications professional specialist college students, undergraduates, graduate students and teachers.
u It adopts entire board design, and each experiment module is independent respectively, special optic devices are protected by glass over, SMT, and module components are full symmetrical.
u It is composed of optical transmitter and receiver module 1550nm, 1310nm and 850nm, analog signal source, digital signal source, serial communication module, telephone module, digital terminal, the main loop and back up loop and other components, and the back-up loop can also be used for secondary development module to connect with other modules seamlessly. Experiment project consists of seven components: fiber and cable, communication light devices ( active and passive devices) , digital fiber optic communication system ( light transmitter, light receiver) , analog fiber optic communication system, optical fiber communication new technology, optical fiber communication network.
u Based on SDH design and combined with SDH technology, it develops basic communication frame structure, to achieve multi-point cross-service signal ( such as digital signal, telephone voice signal) transmission, and also develops 2M frame structure which is appropriate to teaching by refer to SDH and E1 signal frame structure, thus let students to understand the basic optical communication technology.
u It also provides 5B6B, 5B1P, 5B1C, CMI and descrambling codes line code pattern, thus students can further understand the line pattern role in the process of optical transmission.
u It has multicomputer network communication function, and several devices can compose ring network via fiber optic connection to complete digital and voice signals multi-point transmission. Voice signal uses no.1 signaling for relay, which is consistent with commercial equipment, and it can also use dual-fiber communication mode to achieve self-healing ring protection.
u It adopts large scale FPGA as experiment platform, and also be equipped with secondary development board to achieve lots of secondary development experiments.

II. Performance Parameters
Æ AC-DC power supply
Input: AC: 220V ± 10% 50 ± 5Hz
Output: DC: + 5 V/ 3A, -24 V/ 1A, -48 V/ 0.5A, + 3.3 V/ 0.8A, + 1.5 V/ 0.8A
Æ Analog signal source
Output waveform: triangle wave, sine wave
Sine wave: frequency: 1KHz., 1k ~ 8kHz continuously adjustable;
Frequency output error: d ± 1% ;
Amplitude: 0V ~ 5V continuously adjustable.
Triangle wave: frequency: 1KHz., 1k ~ 8kHz continuously adjustable;
Frequency output error: d ± 1% ;
Amplitude: 5V
Æ Digital signal source
Output waveform: 64Kbps 8-bit digital signal, 3-way, the data can be set by yourself
Signal amplitude: 5V
Æ Communication rate
Digital baseband signal: 2048KHz
Æ Light transmitting and receiving module
l 1310 nm light transmitting module: work rate d 155Mbps, center wavelength 1310 ± 20nm, spectrum width d 5 nm, operating current d 35mA, output power 400¼ W ( typical value) , fiber properties: single-mode FC-type interface.
l 1310 nm light receiving module: high responsivity InGaAs planar PIN detector, working wavelength 1100-1650nm, input optical power d 3dBm, 3dB bandwidth of 2GHz, responsivity 0.85A / W ( typical value) , fiber properties: single-mode FC-type interface.
l 1550 nm light transmitting module: work rated2.5Gbps, center wavelength 1550 ± 20nm.spectrum widthd5 nm.operating currentd35mA.output powerd500¼ W.optical interface: FC type.
l 1550 nm light receiving module: high responsivity InGaAs planar PIN detector, working wavelength 1100-1650nm.input optical powerd3dBm.3dB bandwidth 2GHz.responsivity 0.85A/ W typical value , optical interface: FC type.
l 850 nm light transmitting module: work rated155Mbps.center wavelength 850 ± 50nm.spectrum widthd30 nm.operating currentd70mA.output powerd250mW.optical interface: multi-mode ST type.
l 850 nm light receiving module: working wavelength 800-950nm.responsivity 0.8A/ W  typical value , optical interface: multi-mode ST type.
Æ Phone unit
Two telephone interface units can complete the voice signal encoding and decoding, achieving call feature.
Æ CPU host controller module
It mainly includes core control chip EP1C12, upload and download of all business information, conversion of all kinds of optical fiber communication code pattern and voice business 1 # signal control.
Æ External features:
Size: 510mm × 345mm × 125mm
Weight: no more than 5Kg
Æ Working conditions:
Temperature: -10  ~ + 40 
Relative humidity: d 85% ( 25  )

III. Experiment Contents
1 Optical fiber communication system electrical interface
l User’ s telephone interface
l PCM encoding and decoding
l Pseudo-SDH frame structure and transmission
l TDM demultiplexing
l Optical line interface pattern HDB3 encoding and decoding
l Computer data transmission system
2 Light source and light modulation and demodulation
l Digital modulation principle
l Semiconductor laser P-I characteristic test
l LED P-I characteristic curve
l Automatic optical power control
l Light device lifetime detection and no light warning
l Light transmitter characteristic test
l Photoelectric detector characteristic test
l Light receiver principle
l Digital light receiver characteristic test
3 Analog signal optical fiber transmission
l Analog signal optical fiber transmission
l Analog baseband signal transmission distortion and compensation
l Image optical fiber transmission system
4 Digital signal optical fiber transmission
l Bit synchronization signal extraction and code rate change
l Optical fiber communication system circuit scrambling code and descrambling code
l Optical fiber communication system circuit code pattern CMI coding and decoding
l Optical fiber communication system circuit code pattern 5B6B coding and decoding
l Optical fiber communication system circuit code pattern 5BIP coding and decoding
l Optical fiber communication system circuit code pattern 5BIC coding and decoding
l Telephone fiber optic transmission system
l Digital signal optical fiber transmission
5 Optical fiber communication network and new technology
l WDM technology
l Optical fiber communication network system
l Voice + image + data fiber optic transmission system
6 Optical fiber communication system measurement technology
l Multimode fiber loss test
l Single-mode fiber bending loss test
l Optical fiber flexible connector loss test
l Splitter loss and splitting ratio test
l WDM insertion loss and optical crosstalk test
l System eye pattern, vibration test
l Circuit code pattern error monitoring and error diffusion measurement
l Bit error rate test
7 Secondary development
l M sequence program design
l Optical fiber communication system circuit interface code pattern HDB3 code coding and decoding program design
l Scrambling and de-scrambling code program design
l CMI code coding anf decoding program design
l 5B6B code coding anf decoding program design
l 5B1P code coding anf decoding program design
l 5B1C code coding anf decoding program design
l Optical fiber communication self-healing network set up and simulation