Radio tele-communication system using TDMA scheme to reduce signal interference

Claim 2

A radio tele-communication system comprising: a plurality of base stations; a plurality of mobile stations connected to said base stations through radio channels; at least one radio frequency being shared by said plurality of base and mobile stations; a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots; time intervals for detecting timing shifts being set between the plurality of time slots; and each of said base stations and said mobile stations including; timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 3

A system according to claim 1, wherein each of the time intervals for detecting timing shifts is time-divisionally divided into a plurality of sub-intervals, said timing shift detecting means detects a communication timing shift amount during a signal reception state in each of the plurality of sub-intervals, and said timing correcting means corrects the communication timing of the corresponding time slot on the basis of the communication timing shift amount detected by said timing shift detecting means.

Claim 4

A radio tele-communication system comprising: a plurality of base stations; a plurality of mobile stations connected to said base stations through radio channels; at least one radio frequency being shared by said plurality of base and mobile stations; a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots; time intervals for detecting timing shifts being set between the plurality of time slots, wherein a specific code is inserted in each of said time intervals; and each of said base stations and said mobile stations including; timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts, said timing shift detecting means monitoring whether the specific code is detected upon reception of a time slot currently used for communication, and recognizing a communication timing shift of the time slot when the specific code is detected; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 5

A radio tele-communication system comprising: a plurality of base stations; a plurality of mobile stations connected to said base stations through radio channels; at least one radio frequency being shared by said plurality of base and mobile stations; a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots; time intervals for detecting timing shifts being set between the plurality of time slots, wherein a specific code is inserted in each of said time intervals; and each of said base stations and said mobile stations including; timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts, said timing shift detecting means monitoring whether the specific code is detected upon reception of a time slot currently used for communication, and recognizing a communication timing shift of the time slot when the specific code is detected; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 6

A radio tele-communication system comprising: a plurality of base stations; a plurality of mobile stations connected to said base stations through radio channels; at least one radio frequency being shared by said plurality of base and mobile stations; a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots; time intervals for detecting timing shifts being set between the plurality of time slots; and each of said base stations and said mobile stations including; timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.

Claim 7

A radio tele-communication system comprising: a plurality of base stations; a plurality of mobile stations connected to said base stations through radio channels; at least one radio frequency being shared by said plurality of base and mobile stations; a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots; time intervals for detecting timing shifts being set between the plurality of time slots; and each of said base stations and said mobile stations including; timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.

Claim 8

A system according to claim 4, wherein each of the time intervals for detecting timing shifts is time-divisionally divided into a plurality of sub-intervals, said timing shift detecting means detects a communication timing shift amount during a signal reception state in each of the plurality of sub-intervals, and said determining means checks, on the basis of the communication timing shift amount detected by said timing shift detecting means, whether the communication timing of the corresponding time slot can be corrected.

Claim 9

A mobile station apparatus used in a radio tele-communication system comprising a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 10

A mobile station apparatus used in a radio tele-communication system comprising a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 11

An apparatus according to claim 6, wherein each of the time intervals for detecting timing shifts is time-divisionally divided into a plurality of sub-intervals, said timing shift detecting means detects a communication timing shift amount during a signal reception state in each of the plurality of sub-intervals, and said timing correcting means corrects the communication timing of the corresponding time slot on the basis of the communication timing shift amount detected by said timing shift detecting means.

Claim 12

A mobile station apparatus used in a radio tele-communication system comprising a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication from a reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.

Claim 13

A mobile station apparatus used in a radio tele-communication system comprising a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication from a reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.

Claim 14

A base station apparatus used in a radio tele-communication system including a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 15

A base station apparatus used in a radio tele-communication system including a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication during a signal reception state in the time intervals for detecting timing shifts; and timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, on the basis of the communication timing shift detection result obtained by said timing shift detecting means.

Claim 16

An apparatus according to claim 9, wherein each of the time intervals for detecting timing shifts is time-divisionally divided into a plurality of sub-intervals, said timing shift detecting means detects a communication timing shift amount during a reception state in each of the plurality of sub-intervals, and said timing correcting means corrects the communication timing of the corresponding time slot on the basis of the communication timing shift amount detected by said timing shift detecting means.

Claim 17

A base station apparatus used in a radio telecommunication system including a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication from a reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.

Claim 18

A base station apparatus used in a radio telecommunication system including a plurality of base stations and a plurality of mobile stations connected to said base stations through radio channels, at least one radio frequency being shared by said plurality of base and mobile stations, a signal transmitted at the radio frequency having a time frame constituted by a plurality of time-divisionally multiplexed time slots, and time intervals for detecting timing shifts being set between the plurality of time slots, the apparatus comprising: timing shift detecting means for detecting a communication timing shift in a time slot currently used for communication from a reception state in one of the time intervals for detecting timing shifts; determining means for checking, on the basis of the communication timing shift detection result obtained by said timing shift detecting means, whether a communication timing of the corresponding time slot can be corrected; timing correcting means for correcting the communication timing of the corresponding time slot in cooperation with a station, with which communication is performed, if said determining means determines that the communication timing can be corrected; and channel changing means for changing the time slot in cooperation with the station with which communication is performed, if said determining means determines that the communication timing cannot be corrected.