Optoelectronics 1: Devices for Optical Communications
Optical Transmitters (Based on Optisystem software)
Objective:
To familiarize with Optisystem package, a comprehensive software design suite that enables
users to plan, test, and simulate optical links in the transmission layer of modern optical
networks.
To study the design and main characteristics of optical transmitters for optical communication
systems using Optisystem software.
Equipment:
•
PC with Optisystem package;
•
Optisystem tutorials and documentation.
Method:
1.
Complete exercises of Lesson 1 (Optisystem Tutorials Volume 1)
2.
Using the corresponding expression in the tutorial section “LED modulation response”
and the default values of the carrier lifetime and the RC constant (1 ns and 1 ns) for an LED,
calculate the 3-dB modulation optical bandwidth for the LED.
Using the “LED modulation response” sample project file:
i)
ii)
Calculate and compare the eye diagrams for the following bit rates: 50, 100, 150,
200, 250, 300 Mb/s. Save the results as bmp files, comment on the performance of
the LED with an increase in the bit rates.
Carry out similar analysis for a fixed bit rate (300 Mb/s), and reducing both the
carrier lifetime and the RC constant to 0.1 ns. Comment on the result.
3.
Using the corresponding expression in the tutorial section “Semiconductor laser
modulation response” and the default parameters of the laser rate equation model
(Ith = 33.45 mA, sp = 1 ns, ph = 3ps, modulation peak current I = 40 mA and IB = 40 mA),
calculate the corresponding resonance frequency.
Using the “Semiconductor laser modulation response” sample project file, investigate the
influence of the modulation frequency and bias current on the modulation response of the
semiconductor laser:
i)
ii)
Calculate and compare the eye diagrams for the bit rates of 1.3 Gb/s and 10Gb/s.
Save the results as bmp files, comment on the performance of the semiconductor
laser.
Carry out similar analysis for a fixed bit rate (1.3 Gb/s), reducing the bias current
to 20 mA. Comment on the result.
4.
Study the tutorial section “LED spectral distribution”, investigate the influence of the
OSA resolution on analysis of the spectral distribution of an LED. Illustrate your findings with
corresponding bmp images from the OSA visualizer.
5.
Using tutorial section ”Semiconductor laser L-I curve” and the corresponding sample
project file, plot the L-I curve for the semiconductor laser with default parameters.
6.
Complete the exercise series from the tutorial section “Vertical-Cavity Surface-Emitting
Laser - VCSEL Validation”. Document and comment on your results.