Transmitter outage reporting

Abstract

If a cellular base station detects that it is about to shut down, either because no mobile terminals are within range, or because of a loss of power, for example because a user has deliberately switched it off, it first broadcasts a report that is about to shut down. This broadcast signal is picked up by the neighboring cells and used to update their neighbor lists, thus avoiding a false alarm which would otherwise be generated by the neighbors and transmitted to a centralized Operation Administration and Maintenance system when the shut-down cell fails to be detected on the next sampling cycle. The neighbors can then retain the shut-down base station in the neighbor list. The cause of the shut-down may be identified in the shut-down report, and a self-organizing frequency reuse plan adjusted if the base station is shut down altogether (for example because of a loss of power) but remain unchanged if the base station is continuing to operate in receive-only mode because no mobile terminals are within its range. The base station has a standby battery which allows a 'graceful' shutdown even if the main power supply is cut off.