PURPOSE: To ensure changeover of a packet channel against interference by inhibiting tentatively access of all terminal stations under a control station so as to detect the presence of interference in a state without occurrence of collision thereby accurately separating causes to signal error into collision and interference.
CONSTITUTION: In the mobile radio packet communication system dividing a packet signal into plural slots for communication, an inhibit signal 4-5 is sent just after collision takes place in a head packet to inhibit access of all terminal stations. When an interference save 4-7 is in existence, a signal is observed by a discrimination slot 4-8 independently of the inhibit signal 4-5 and an error 4-9 is generated in other slots than a head slot of the packet signal sent in a form of consecutive slots. Thus, the presence of inter-channel interference is correctly discriminated even in the mobile communication system conducting packet multiplexing with random access by discriminating collision and interference depending whether or not control from a control station is available.
ICHIKAWA TAKEO
IIZUKA MASATAKA
KUNO YUTAKA
