User-invoked re-routing of an incoming call via a stronger serving system

In a wireless communication device (WCD) registered with a first wireless serving system and being served by the first wireless serving system via a first air interface between the first wireless serving system and the WCD, a method comprising:

• detecting an incoming call being set up to the WCD via the first wireless serving system;
• detecting a threshold low signal strength being received into the WCD from the first wireless serving system and a threshold high signal strength being received into the WCD from a second wireless serving system;
• responsive to detecting the incoming call being set up to the WCD via the first wireless serving system and detecting the threshold low signal strength being received into the WCD from the first wireless serving system and a threshold high signal strength being received into the WCD from a second wireless serving system, (i) notifying a user of the WCD of the incoming call and (ii) prompting the user to request the incoming call to be re-routed to the WCD via the second wireless serving system instead of via the first wireless serving system;
• receiving from the user, in response to the prompting, a request to re-route the incoming call to the WCD via the second wireless serving system;
• and
• responsive to the user's request, invoking a process to re-route the incoming call to the WCD via the second wireless serving system instead of via the first wireless serving system,
• wherein invoking the process to re-route the incoming call to the WCD via the second wireless serving system instead of via the first wireless serving system comprises (a) during set up of the incoming call to the WCD via the first wireless serving system, (i) sending from the WCD to the first wireless serving system a Flash With Information message directing the incoming call to be forwarded to a mediation server, and (ii) registering with the second wireless serving system, wherein the mediation server then sets up the incoming call to the WCD, and the call connects to the WCD via the second wireless serving system since the WCD is registered with the second wireless serving system.

A system for forced handoff of a call that is being set up to a wireless communication device (WCD) via a first wireless serving system with which the WCD is currently registered, the system comprising:

• trigger logic in the WCD;
• re-routing logic in the WCD;
• and
• a mediation server,
• wherein the trigger logic is operable by the WCD (i) to detect, during set up of the incoming call, that threshold stronger signal strength is available from a second wireless serving system than the WCD is receiving from the first wireless serving system, (ii) to responsively offer a user of the WCD an option to have the incoming call re-routed to the WCD via the second wireless serving system instead of via the first wireless serving system, and (iii) to respond to user acceptance of the offer by invoking the re-routing logic,
• wherein the re-routing logic is operable by the WCD (i) to signal to the first wireless serving system to forward the incoming call to the mediation server, (ii) to register with the second wireless serving system, so as to facilitate receiving the incoming call from the mediation server via the second wireless serving system, and
• wherein the mediation server operates to set up the incoming call to the WCD, whereby the incoming call then extends from the mediation server to the WCD via the second wireless serving system.