Multiwavelength self-seeded Fabry-Perot laser with subharmonic pulse-gating for two-dimensional fiber optic-CDMA

A new scheme using self-seeding in a gain-switched Fabry-Perot (F-P) laser with subharmonic pulse gating in an external cavity consisting of a string of fiber Bragg gratings (FBG) for incoherent two-dimensional fiber-optic code division multiple access applications is proposed and demonstrated experimentally. Three-wavelength optical pulses are generated sequentially with pulsewidths of 78 ps at a repetition rate of 250 MHz, and side-mode suppression ratio better than 20 dB. The FBG position deviation has been confirmed not to affect the laser operation if the resulting pulse position deviation is within the gating pulsewidth. The generated optical pulses are much more stable and intense than those obtained directly from the gain-switched F-P laser.