As shown in FIG. 6, one or more processors 210a of the first communication device 200a may determine that beacon beam 24b transmitted from the second communication device 200b is not properly aligned using receiver 240a. The one or more processors 210a may determine that beacon beam 24b is absent from image frames received at receiver 240a via first optical system 250a. The absence may be detected to be an extended absence that is longer than a threshold length of time and not a brief outage due to turbulence or obstruction. In addition, the one or more processors 210a may also determine that no communications or data 23 has been received at receiver 240a via an optical beam from the second communication device 200b for a threshold length of time. Additionally or alternatively, one or more processors 210b of the second communication device 200b may similarly determine that beacon beam 24a and/or an optical beam being transmitted from the first communication device 200a is not properly aligned using receiver 240b.
