Cellular telephone network routing method and apparatus for internationally roaming mobile stations

摘要

The registration notification signal sent to the home cellular system when an internationally roaming cellular mobile station registers in a foreign cellular system includes an identification of the currently serving switching node. Upon subsequent receipt of an incoming call dialed to the roaming mobile station home directory number, the home cellular system signals the serving cellular system and a temporary local directory number is assigned and returned to the home cellular system. The switching node identification is then processed to identify the proper international dialing digits for calling the country where the serving switching node is located. The returned temporary local directory number is then appended to the identified international dialing digits to form an international telephone number which is used by the home cellular system to route the received call to the currently serving cellular system for delivery to the called internationally roaming mobile station.