Mobile radio communication system permitting a mobile station to specify a base station used by the same

• US 5,745,855 A
• Filed: 08/28/1995
• Issued: 04/28/1998
• Est. Priority Date: 08/26/1994
• Status: Expired due to Fees

• Current Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Futamura, Yoshisumi
• Primary Examiner(s): Pham, Chi H.
• Application Number:
  US08/519,728
• Time in Patent Office: 974 Days
• Field of Search: 455/53.1, 455/54.1, 455/52.1, 455/33.1-34.1, 455/67.1, 455/507, 455/517, 455/524, 455/525, 340/825.08, 340/825.54, 340/505, 342/50, 342/51
• US Class Current: 455/517
• CPC Class Codes: G05D 1/0022 characterised by the communication link data switching networks in general H04L12/00
• CPC Class Codes: G05D 1/0282 generated in a local control room

Abstract

Through a technique such as a carrier sense system or the like, a mobile station (14) identifies a base station (12) (requested base station) by which the mobile station is to be controlled. In response to polling from a key station (10), the base station informs the key station (10) of the requested base station. When the key station (10) performs the polling to know that a receiving base station which obtained the response is different from the requested base station, the next polling will be made through both the base stations (12). If the key station receives the response from the requested base station, the key station switches the base station controlled by itself from one to another.

Claims

1. A mobile radio communication system configured to perform a polling operation, comprising:

a key station that communicates with a plurality of mobile stations through a plurality of base stations, wherein one of said mobile stations sends to the key station identification information of a base station to be used next in said polling operation,

the key station then switching a polling path so as to include said base station to be used next when communicating with said mobile station as identified by said identification information,

said mobile station switching the polling path such that a polling response will be returned therefrom to the key station through said base station to be used next,

said mobile station being configured to send to said key station in the polling response said identification information of the base station to be used next, and

said key station determining the polling path in accordance with the identification information and adding said base station to be used next to said polling path if said base station to be used next is not in currently in said polling path.

2. A mobile radio communication system according to claim 1 wherein the key station compares the base station to be used next indicated by the identification information from said mobile station and a base station which received the polling response from said mobile station, and said key station will carry out the polling to said mobile station through both base stations until the base station to be used next matches a base station which received the polling response of said mobile station.

3. A mobile radio communication system according to claim 1 wherein the key station sends the identification information of a base station switched on the basis of the identification information of the base station to be used next to said mobile station which sent said identification information, thereby indicating which base station should be used by said mobile station.

4. A mobile radio communication system according to claim 1, comprising a previously stored table containing the correspondent relationship between a position of a mobile station and a base station which should be used, and when the mobile station sends information of the position, the key station refers to the table and determines which base station should be used by said mobile station.

5. A mobile radio communication system according to claim 1 wherein the communication is carried out while switching between a carrier sense system in which a base station to be used next is identified by a mobile station on the basis of the state of carrier reception from a plurality of the base stations, the identity of the identified base station being then informed to the key station, and an area assignment system in which a mobile station sends information of its position and the key station determines a base station to be used next in accordance with the sent position of said mobile station.

6. A mobile radio communication system according to claim 5 wherein at a preselected location, a mobile station senses its own position from a position sensing marker on a path of mobile station travel, and said mobile station sends its position when said position sensing is carried out, while it sends the state of the carrier reception when said position sensing could not be carried out.

7. A mobile radio communication system according to claim 1 wherein the key station includes a base station registry table representing the correspondent relationship between a mobile station and a receiving base station and wherein when the key station receives the polling response from a mobile station, the receiving base station is renewed to the base station which received the communication from the mobile station.

8. A mobile radio communication system according to claim 7 wherein said base station registry table also describes the correspondent relationship between a mobile station and a requested base station to be used next by said mobile station and wherein when the identification information of a base station to be used next is sent from a mobile station to the key station, the base station registry table registers a base station specified by said identification information as the requested base station.

9. A mobile radio communication system according to claim 8 wherein the key station compares the receiving and requested base stations in the base station registry table and wherein if these base stations match each other, the key station uses said base station to carry out the polling to said mobile station and if not, the key station uses both the base stations to carry out the polling to said mobile station.

10. A mobile radio communication system according to claim 9 wherein during the setup of said system, the same base station is registered for all the mobile stations in said base station registry table as a receiving base station.

11. A mobile radio communication system according to claim 10 wherein during the setup of said system, a base station different from the receiving base station is registered for all the requested base stations in said base station registry table.

12. A mobile radio communication system according to claim 11 wherein said base station registry table can register a plurality of requested base stations for one mobile station and wherein all the receiving and requested base stations for one mobile station are set to be different from one another.

13. A mobile radio communication system according to claim 9 wherein said base station registry table can register a plurality of requested base stations for one mobile station and wherein when it becomes impossible for a mobile station to communicate, said base station registry table sets all the receiving and requested base stations for said mobile station to be different from one another.

14. A mobile radio communication system according to claim 1 wherein the signal from the key station is received by a plurality of mobile stations through a plurality of base stations.

15. A mobile radio communication system according to claim 14 wherein said plurality of base stations send the same signal designating a mobile station toward a plurality of the mobile stations and wherein only the designated mobile station returns the polling response to said base stations.

16. A mobile radio communication system according to claim 1 wherein all the base stations have the same signal frequency and in which one communication is carried out between one base station and one mobile station.

17. A mobile radio communication system according to claim 16 wherein the key station includes a table of mobile stations to communicate with all the base stations and wherein the key station performs the sequential communication with all the mobile stations through the base stations according to said table.

18. A mobile radio communication system according to claim 17 wherein a base station having no mobile station to communicate therewith sends a signal that does not specify any mobile station to be designated in the communication.

19. A mobile radio communication system according to claim 18 wherein each of said mobile stations has a carrier sense function of sensing and comparing the levels of received signals from said plurality of base stations and wherein said mobile station can specify a base station having the highest level of received signal as a base station to communicate with itself.