Fabrication and performance analysis of cost-effective fiber grating lasers for WDM-PON systems

Fiber-Bragg-grating external cavity laser(FGL) modules were fabricated and experimentally analyzed. Proposed as a cost-effective solution for optical sources in the WDM-PON access network, FGL modules were packaged to TO-CAN type. We obtained a low threshold current of 13 mA, and an optical output power of 3.6 mW with a bias current of 60 mA at 25 degrees C. The lasing wavelength dependencies on current and temperature were as small as 5.2 pm/mA and 30 pm/degrees C, respectively. These change rates of the wavelength with the temperature and current are smaller than those of the DF Blaser. Single-mode oscillations with the side-mode suppression ratio(SMSR) over 30 dB are maintained above the threshold current level. The FGL modules can be directly modulated at 155 Mbps, PRBS(2(23)-1) NRZ signal. Through the BER plots, we did not see the significant degradations before and after the transmission over 20km of the SMF at 155 Mb/s.