Patent ID: 6453172
Filing Date: 2002-09-17
Classification: H04W

Abstract:
A dual band portable phone comprising:a first mobile phone system used in a first mode; a second mobile phone system used in a second mode; a storing section having a mode area for storing a mode data indicative of a current operation mode, a first area for storing a first control channel data indicative of a first control channel used for said first mobile phone system in said first mode, and a second area for storing a second control channel data indicative of a second control channel used for said second mobile phone system in said second mode, the mode data indicating said first mode; a control section for performing a position registration of said portable phone using said second control channel data stored in said storing section to set said second mode, when a first radio communication using said first mobile phone system becomes impossible while said first radio communication is performed in said first mode, and for performing a second radio communication using said second mobile phone system, wherein said control section performs a position registration of said portable phone using said first control channel data stored in said storing section in response to a mode change request while said second radio communication is performed in said second mode, sets said first mode in response to the position registration of said portable phone using said first control channel data, and performs a radio communication using said first mobile phone system, further comprising a timer, and wherein said mode change request is issued by said timer when said portable phone in said second mode is located in a service area of said first mobile phone system.