Wireless mobile telephone system with zone selection control

• US 5,539,923 A
• Filed: 03/22/1994
• Issued: 07/23/1996
• Est. Priority Date: 03/26/1993
• Status: Expired due to Term

• Current Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Original Assignee: Mitsubishi Denki Kabushiki Kaisha (Mitsubishi Electric Corporation)
• Inventors: Matsumoto, Shinji
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): TO, DORIS HA
• Application Number:
  US08/215,784
• Time in Patent Office: 854 Days
• Field of Search: 455/33.1, 455/33.3, 455/33.4, 455/34.2, 455/34.1, 455/54.1, 455/54.2, 455/56.1, 455/67.1, 455/33.2, 379/58, 379/59, 379/60
• US Class Current: 455/443
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 72/27 between access points

Abstract

A mobile telephone apparatus operates as follow: when an origination signal is transmitted from the mobile station, the base station of a wireless zone where the mobile station is not present communicates a connection possible signal to the base station in the zone where the mobile station is present, and the base station having a larger number of idle channels than that of the other base station is selected on priority basis independent on the signal intensity. Therefore, when the origination signal from the mobile station is received by a plurality of base stations, the base station having the receiving level larger than the required minimum receiving level and having the maximum number of idle channels is selected, and it is possible to reduce the origination loss rate relative to the conventional system.

Claims

1. A wireless mobile telephone system, comprising:

a plurality of base stations disposed so that each base station has its own wireless zone overlapping with the wireless zone of other base station to some extent;

a mobile station moving over the wireless zones produced by said base stations and performing a telephonic communication with any of said plurality of base stations;

said each of the base stations including;

a means for transmitting, when it is a non existing-in-zone base station in the zone of which the mobile station is not present and receives an origination signal from the mobile station at the start of telephonic communication, a connection possible signal to the existing-in-zone base station in the zone of which the mobile station is present;

a means for selecting, when it is an existing-in-zone base station and it receives the origination signal from the mobile station, a base station which has a receiving level larger than the required minimum receiving level and the maximum number of possessing idle channels among all the other base stations which have transmitted the connection possible signal and a self terminal of the existing-in-zone base station, as a base station to be connected with the mobile station; and

and wherein said non existing-in-zone base station communicates, when it receives said origination signal from said mobile station and has an idle channel, that a connection with that mobile station is possible as well as idle channel Nos., the number of idle channels, and the receiving level to the existing-in-zone base station.

2. A wireless mobile telephone system, comprising:

a plurality of base stations disposed so that each base station has its own wireless zone overlapping with the wireless zone of other base station to some extent;

a mobile station moving over the wireless zones produced by said base stations and performing a telephonic communication with any of said plurality of base stations;

said each of the base stations including;

a means for transmitting, when it is a non existing-in-zone base station in the zone of which the mobile station is not present and receives an origination signal from the mobile station at the start of telephonic communication, a connection possible signal to the existing-in-zone base station in the zone of which the mobile station is present; and

a means for selecting, when it is an existing-in-zone base station and it receives the origination signal from the mobile station, a base station which has a receiving level larger than the required minimum receiving level and the maximum number of possessing idle channels among all the other base stations which have transmitted the connection possible signal and the self terminal which is the existing-in-zone base station, as a base station to be connected with the mobile station;

said base station performing waiting receiving of an up control channel of any of peripheral base stations by changing a frequency of an idle channel during waiting receiving the self station control channel;

said base station performing waiting, for a prescribed time, presence of a connection possible signal from any of said peripheral base stations when it receives a connection request signal from the mobile station through the self station control channel in said waiting receiving state;

said base station selecting, when it receives a connection possible signal from other base station and a prescribed time passes over, the base station which has a receiving level above the required minimum receiving level and has the maximum number of idle channels among the base stations the connection possible signal from which the base station received and the self base station, as a base station to be connected with the mobile station;

said base station acts, after the selection, as follows;

when the selected base station is the self station, it transmits a channel releasing instruction to all the base stations which have transmitted connection possible signals and transmitting a channel designating signal designating a voice channel of the self terminal to the mobile station to establish a communication path;

when the selected base station is other base station it transmits channel releasing instructions to the non-selected base stations among the base stations which have transmitted the connection possible signals and a connection instruction to the selected terminal, transmits a channel designating signal designating a voice channel of the selected terminal to the mobile station, and returns to the waiting receiving state;

said base station, when it receives the connection possible signal from the mobile station through the other terminal control channel during the above-described waiting receiving state, transmits a connection possible signal to the existing-in-zone terminal and waits an instruction from the existing-in-zone base station when it has an idle channel, and returns again to the waiting receiving state when it has no idle channel;

said base station, when it receives a connection instruction from the existing-in-base terminal during waiting an instruction from the existing-in-zone base station, establishes a communication path; and

said base station, when it receives a channel releasing instruction during waiting an instruction from the existing-in-zone base terminal, returns to the waiting state.

3. A wireless mobile telephone system, comprising:

a plurality of base stations disposed so that each base station has its own wireless zone overlapping with the wireless zone of other base station to some extent;

a mobile station moving over the wireless zones produced by said base stations and performing a telephonic communication with any of said plurality of base stations;

said each of the base stations including;

a means for transmitting, when it is a non existing-in-zone base station in the zone of which the mobile station is not present and receives an origination signal from the mobile station at the start of telephonic communication, a connection possible signal to the existing-in-zone base station in the zone of which the mobile station is present;

a means for selecting, when it is an existing-in-zone base station and it receives the origination signal from the mobile station, a base station which has a receiving level larger than the required minimum receiving level and the maximum number of possessing idle channels among all the other base stations which have transmitted the connection possible signal and a self terminal of the existing-in-zone base station, as a base station to be connected with the mobile station;

and wherein said existing-in-zone base station includes means for transmitting, when the number of idle channels of the self station becomes below a prescribed value during continuing a communication with the mobile station, a retransmitting request signal requesting all other base stations which receive the origination signal from the mobile station above a prescribed level to retransmit a connection possible signal.

4. A wireless mobile telephone system, comprising:

a plurality of base stations disposed so that each base station has its own wireless zone overlapping with the wireless zone of other base station to some extent;

a mobile station moving over the wireless zones produced by said base stations and performing a telephonic communication with any of said plurality of base stations;

said each of the base stations including;

a means for transmitting, when it is a non existing-in-zone base station in the zone of which the mobile station is not present and receives a signal from the mobile station during when an existing-in-zone terminal in the zone of which the mobile station is present continues a telephonic communication with the mobile station, and when the receiving level is above the required minimum receiving level and the number of idle channels is larger than a prescribed value for the self non existing-in-zone terminal, a connection possible signal to the existing-in-zone base station;

a means for comparing, when it is the existing-in-zone base station and it receives the connection possible signal, the numbers of idle channels of the self station and the non existing-in-zone base station, and selecting the base station having a larger number of idle channels to continue the communication; and

wherein said each of the base stations which is not the existing-in-zone base station observes the receiving level of the communication channel by an up communication channel of any of peripheral base stations and the non existing-in-zone base station during its observing state, communicates that a connection is possible as well as the idle channel Nos., the number of idle channels, and the receiving level to the existing-in-zone base station when it has an idle channel in this observing state.

5. The wireless mobile system of claim 4 wherein said existing-in-zone base station compares the numbers of idle channels and receiving levels of the self station and the non-existing base station and selects the base station having the receiving level above the required minimum receiving level and the maximum number of idle channels among them, and the selected base station transmits a connection possible signal to the non-selected base station and transmits a connection instruction to the mobile station to establish a voice channel.

6. The wireless mobile telephone system of claim 5 wherein:

the base station of other wireless zone observes the receiving level of an up communication channel of any of peripheral base stations by changing a frequency of one of idle channels and a usage channel of the self station for an instance during observing the communication channel of the other terminal;

the base station of other wireless zone communicates, when it detects that the receiving level exceeds the required minimum receiving level and it has an idle channel, a connection is possible as well as the idle channel Nos., the number of idle channels, and the receiving level to the existing-in-zone base station and enters a state of waiting a response from the existing-in-zone base station;

the base station of other wireless zone, when it receives a connection instruction from the existing-in-zone base station, establishes a communication path and enters an observing state observing voice channels of the self station;

said base station of other wireless zone, when it receives a channel releasing instruction from the existing-in-zone base station, returns to the observing state of observing the voice channel of the other base station;

said existing-in-zone base station, when it receives a connection possible signal from the other base station during observing the voice channel of the self station, performs a sequence of channel switching when the number of idle channels of the other base station is larger than that of the self station, and

when the number of idle channels is smaller than that of the self station, transmits a channel releasing instruction to the other terminal and returns to the state of observing the voice channel of the self station.

7. A wireless mobile telephone system, comprising:

a plurality of base stations disposed so that each base station has its own wireless zone overlapping with the wireless zone of other base station to some extent;

a mobile station moving over the wireless zones produced by said base stations and performing a telephonic communication with any of said plurality of base stations;

said each of the base stations including;

a means for transmitting, when it is a non existing-in-zone base station in the zone of which the mobile station is not present and receives a signal from the mobile station during when an existing-in-zone terminal in the zone of which the mobile station is present continues a telephonic communication with the mobile station, and when the receiving level is above the required minimum receiving level and the number of idle channels is larger than a prescribed value for the self non existing-in-zone terminal, a connection possible signal to the existing-in-zone base station;

a means for comparing, when it is the existing-in-zone base station and it receives the connection possible signal, the numbers of idle channels of the self station and the non existing-in-zone base station, and selecting the base station having a larger number of idle channels to continue the communication; and

wherein said base station includes means for transmitting, when the number of idle channels of the self station becomes below a prescribed value during continuing a communication with the mobile station, a retransmitting request signal requesting all other base stations which receive the signal from the mobile station above a prescribed level to retransmit a connection possible signal.