a method and apparatus is described for a free space optical communication link that transmits and receives an optical signal using phase incoherent light . in one embodiment , the phase incoherent light source may be a superluminescent light emitting diode . use of phase incoherent light reduces signal scintillation by significantly reducing speckle in the transmitted signal . the result is an optical link that does not need an adaptive optical control loop to correct for speckle and that may modularly replace conventional laser - based phase - coherent free space optical links typically used in free space optical link systems . use of the described apparatus and methods results in reduced system size , reduced system weight , reduced system complexity , reduced power consumption , a lower initial system cost , a reduced failure rate , a decreased bit error rate , lower lifecycle maintenance costs , greater reliability , greater link availability , increased link throughput and improved network performance .