Patent ID: 7203481

Claim:
A radio communication system, comprising: a plurality of first communication units; a second communication unit; and a portable terminal establishing radio communication with each of said first communication units; wherein said first communication unit includes storage means for storing identification information for identifying the unit itself and authentication information corresponding to said identification information, and transmission means connected to said storage means, for transmitting said identification information to said portable terminal; said portable terminal includes first reception means for receiving said identification information from said first communication unit, and first transmission means for transmitting said identification information to said second communication unit; said second communication unit includes reception means for receiving said identification information from said portable terminal, first registration means for registering the identification information and the authentication information corresponding to each of said first communication units, search means connected to said reception means and said first registration means, for searching the registered authentication information based on the identification information received from said portable terminal, and transmission means connected to said search means, for transmitting searched authentication information to said portable terminal; said portable terminal further includes second reception means for receiving said searched authentication information from said second communication unit, and second transmission means for transmitting information requesting connection of said portable terminal with said first communication unit to said first communication unit; and said first communication unit further includes reception means for receiving information requesting connection from said portable terminal, and determination means connected to said reception means and said storage means, for determining whether or not connection of said portable terminal to said first communication unit is permitted based on said searched authentication information and said stored authentication information.