1047-NM MASTER OSCILLATOR POWER-AMPLIFIER FREE-SPACE OPTICAL COMMUNICATIONS LASER TRANSMITTER

We report on the performance of a 1047-nm laser diode master oscillato r (MO) diode pumped Nd:YLF power amplifier (PA) laser transmitter in a 50-Mbps quaternary pulse position modulation (Q-PPM) free-space optic al direct detection communications experiment, The transmitter produce d greater I variable Neutral than 1 W of 1047-nm average optical power , At optical transmitter powers up to 0.2 W, we achieved nearly the sa me communications performance (similar to 210 photons/b at 10(-6) bit- error rate) using the 1047-nm MOPA transmitter as with the 50 mW laser diode alone, We relied on an external cavity grating feedback scheme for the 1047-nm laser diode MO to achieve this communications performa nce.