Wireless private branch exchange (WPBX) and communicating between mobile units and base stations

In a wireless communication system comprising a Base Station connected with a mobile unit, a method of synchronizing at least one neighboring Base Station to the Base Station connected with the mobile unit comprising:

• from the Base Station connected with the mobile unit, sending call parameters and rough synchronization information to the at least one neighboring Base Station;
• and
• at the at least one neighboring Base Station, monitoring transmissions of at least one of:
• the Base Station connected with the mobile unit;
• the mobile unit;
• and
• a beacon signal from a beacon transmitter which is within range of the at least one neighboring Base Station and the Base Station connected with the mobile unit.

In a wireless communication system comprising a Base Station connected with a mobile unit, a method of detecting the presence of a specific mobile unit in a coverage area of at least one neighboring Base Station, comprising:

• the Base Station connected with the mobile unit provides, to the at least one neighboring Base Station, information about the connection with the mobile unit, including rough TOD and a device address for the mobile unit;
• at the at least one neighboring Base Station, receiving information and generating a list of frequencies in which the mobile unit is likely to transmit;
• and
• at the at least one neighboring Base Station, checking for a signal transmitted by the mobile unit.

In a wireless communication system comprising at least two Base Stations, at least one Switch in communication with the Base Stations, and at least one mobile unit, a method of handing off the mobile unit from a Base Station communicating with the mobile unit and a neighboring Base Station, comprising:

• smoothing a plurality of signals received from a handset by a plurality of Base Stations;
• comparing the signals with one another;
• and
• selecting a Base Station for handoff based on signal quality.

In a wireless communication system comprising at least two Base Stations and at least one Switch in communication with the Base Stations, a method of performing handoff of a session from a Base Station connected with a mobile unit to a neighboring Base Station, wherein an instance of a low-level communications protocol is running at the Base Station connected with the mobile unit, comprising:

• at the Switch, determining when to perform handoff to a selected one of the neighboring Base Stations;
• at the selected one of the neighboring Base Stations, creating a copy of the low-level communications protocol, including at least a synchronized time of day (TOD) parameter;
• from the Switch, sending a command to stop communication with the mobile unit at a specified TOD to the Base Station connected with the mobile unit and sending a command to start communication with the mobile unit at the specified TOD to the selected one of the neighboring Base Stations;
• and
• updating session status tables in the Switch and in the Base Stations.

In a wireless communication system comprising a Base Station connected with a mobile unit, a method of detecting and synchronizing with the mobile unit prior to receiving a handoff of a session with the mobile unit, comprising:

• from the Base Station connected with the mobile unit, sending rough synchronization information to at least one neighboring Base Station;
• at the neighboring Base Station, performing a wide-range search for “target” signals having the correct timing for a mobile unit, based on the rough synchronization information provided by the Base Station which is connected with the mobile unit;
• narrowing the search for an actual signal from the mobile unit;
• acquiring the target signal;
• and
• synchronizing the neighboring Base Station to the Base Station connected with the mobile unit.