Towards the end of September the US Maritime Administration (MARAD) issued an advisory notice (No 2020-016) concerning GPS interference.
Multiple instances of significant GPS interference have been reported worldwide in the maritime domain. This interference is resulting in lost or inaccurate GPS signals affecting bridge navigation, GPS-based timing, and communications equipment. Satellite communications equipment may also be impacted.
Over the last year, areas from which multiple instances have been reported include the eastern and central Mediterranean Sea, the Persian Gulf, and multiple Chinese ports. The US Transportation Command “Message for Industry” at https://go.usa.gov/xdSpq provides additional GPS interference information.