Patent ID: 6915127

Claim:
A radio base station of a mobile communication system that accommodates a plurality of mobile stations through radio lines and that control call connections, said radio base station comprising: a line control means for controlling connections with radio base station controllers that control a plurality of radio base stations through wired lines and that mediate communication with partner mobile stations of said mobile stations; radio transceiving means for communicating with each of said mobile stations by radio frequency signals; a plurality of radio communication modems that are each assigned to a call connection of each of said mobile stations for performing mutual conversion between signals of radio sections for said radio transceiving means and signals of wired sections for said line control means; fault detection comparison data storage means for storing fault detection comparison data for comparison with the content of frames that are received for each of said radio communication modems to detect faults; total received frame counting means for counting the total number of frames that are received for each of said radio communication modems; fault detection frame counting means for counting the number of frames in which a fault is detected of frames that are received for each of said radio communication modems based on said fault detection comparison data; modem fault detection threshold value storage means for storing a modem fault detection threshold value, which is the maximum value of the ratio of said number of frames in which a fault is detected to said total received frames for determining a fault of a relevant radio communication modem for each of said radio communication modems; and a central control means for monitoring each of said radio communication modems, and when a call connection is terminated, calculating the ratio of said number of frames in which a fault is detected to said total received frames of the relevant radio communication modem, comparing this calculated ratio with said modem fault detection threshold value, and when this calculated ratio exceeds said modem fault detection threshold value, determining that a fault has occurred and causing the execution of an automatic recovery process of the relevant radio communication modem.