Telecommunications – Transmitter and receiver at separate stations – Single message via plural carrier wave transmission
Patent
1993-10-20
1995-06-27
Eisenzopf, Reinhard J.
Telecommunications
Transmitter and receiver at separate stations
Single message via plural carrier wave transmission
455 561, 379 59, H04B 726
Patent
active
054288223
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The invention relates to a radio system comprising at least one local exchange; a radio network comprising fixed radio stations located apart from each other and connected to the local exchange; and at least one mobile radio station capable of roaming freely within the area of the radio network and informing the radio network of its location by selecting one of the fixed radio stations in accordance with a predetermined selection procedure and sending to the base station a registration message which is forwarded to the local exchange.
BACKGROUND OF THE INVENTION
In mobile radio systems where the mobile radios are allowed to roam freely within the area of the system and have access to the system through a base station selected by them, the registrations of the mobile radios are utilized to keep a record of the coarse location of the mobile radios so that the system is capable of routing calls to the mobile radios. Registration can also be used to prevent the access of unauthorized users to the system. The mobile radio performs a registration whenever it changes the registration area by sending a registration message to a base station selected in accordance with a predetermined selection procedure. The registration message is then forwarded to the mobile radio exchange. In some mobile radio systems, such as the NMT (Nordic Mobile Telephone), the mobile radio has to wait for a registration acknowledgement from the mobile radio exchange before it is allowed to attempt to register through another base station. If the mobile radio does not receive a registration acknowledgement, it informs the user about the situation. The problem with unsuccessful registration is thus left to the user. In some other mobile radio systems, such as the Mobile Private Trunking networks complying with the specifications MPT 1327 and MPT 1434 of the British Department of Trade and Industry, attempts have been made to improve the registration procedure from the user's viewpoint so that if a registration to one mobile radio exchange is not successful, the mobile radio has a chance to try to register, very rapidly, to another mobile radio exchange. If the mobile radio attempts to register to several mobile radio exchanges within a short period of time, the mobile radio system may not be able to determine the actual order of the registration messages received by the different mobile radio exchanges, and so the location of the mobile radio is ambiguous. In this kind of system, the failure of the registration or the disordering of successive registrations may result from, e.g., the radio path delays and interferences, the delays and interferences of the internal transmission paths of the central network, and the registration frequency of the mobile radios.
SUMMARY OF THE INVENTION
The object of the present invention is to enable an unambiguous determination of the order of reception of successive registrations in a radio system where a mobile radio is allowed to attempt to register to several mobile radio exchanges.
This is achieved by a radio system of the type described in the introductory part of this specification, which according to the invention is characterized in that the mobile radio station provides the registration messages with information indicating the order of transmission of the messages, on the basis of which information the radio network determines the order of transmission of registration messages sent by the same mobile radio station through the different local exchanges, and that the radio network regards as valid the registration corresponding to the registration message sent last and rejects or cancels the registrations caused by preceding registration messages.
The basic idea of the invention is that the mobile radio station, such as a mobile radio, provides each registration message at the transmission stage with information indicating the order of transmission of the registration messages. Such information may consist, of e.g., a serial number, time or the like. The radio network itse
REFERENCES:
patent: 5247698 (1993-09-01), Sawyer
patent: 5257399 (1993-10-01), Kallin et al.
patent: 5276911 (1994-01-01), Levine et al.
Helenius Ali
Laaksonen Pirkko
Lehtonen Markku
Eisenzopf Reinhard J.
Nokia Telecommunications Oy
Pham Chi H.
LandOfFree
Radio system including mobile radio stations which provide regis does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Radio system including mobile radio stations which provide regis, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Radio system including mobile radio stations which provide regis will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-295993