MATLAB simulation of a distributed feedback (DFB) laser with chirp effects
Espe, Burt Lann
Borchardt, Randy L.
Powers, John P.
MetadataShow full item record
A model of a distributed feedback (DFB) laser was implemented in MATLAB and SIMULINK. Using the laser rate equation, the model was simulated to obtain general characteristics of the chirp of the lasers frequency. The simulations were controlled by using different drive current waveforms, based on various bit patterns, data rates, and drive current values (threshold current and the extinction ratio). Once created, the laser drive current was passed to the SIMULINK DFB laser model. The output of a simulation provided frequency chirp, laser power emitted, photon density, and carrier density data. Two sets of simulations were conducted. The first set of simulations focused on the data rates and bit patterns. From these simulations it was determined that the transition from a ZERO bit to a ONE bit caused the greatest frequency excursions. Also, as the data rate increases the maximum frequency excursion increases. Finally, the first set of simulations revealed that the predictability of the chirp decreases as the data rate increases and as the complexity of the bit pattern increases. The second set of simulations examnined the effect of the extinction ratio on frequency chirp. By plotting the maximum frequency excursion against its respective extinction ratio, it was determined that in some cases the maximum frequency excursions in a system could be minimized.
Showing items related by title, author, creator and subject.
Zhou, Hong (2011);We study the maximum temperature rise induced by a rotating or dithering Gaussian laser beam on a semi-infinite body. An analytical solution is obtained by solving the transient three-dimensional heat equation in a ...
Experimental investigation of damping characteristics of bolted structural connections for plates and shells. Iverson, Jonathan C. (1987);Reducing the contact force in bolted structural connections can reduce system vibration amplitudes by enhancing joint damping capacity. A test model consisting of two concentric circular cylindrical shells and four ...
Wilson, O. B. (Oscar Bryan); Wolf, Stephen N.; Ingenito, Frank (Monterey, California. Naval Postgraduate School, 1982-12); NPS-61-83-006Horizontal directionality of ambient noise was measured at ranges up to 15 km from the south-eastern shore of Monterey Bay, California. Water depths at the sites ranged from 8 to 175 m. A steerable cardioid receiving pattern ...