LOS

LOS can be expanded in two ways:

• loss of signal

  A field in a SONET frame that indicates the loss of line signaling.

• line of sight

  The propagation characteristic of high-frequency radio is called line-of-sight. Any obstruction between a transmitting antenna and a receiving antenna will block a signal. The ability to visually see a transmitting antenna roughly corresponds to the ability to receive a radio signal from it.