Personal communication system and technique with zone report feature

• US 6,148,210 A
• Filed: 11/22/1999
• Issued: 11/14/2000
• Est. Priority Date: 03/12/1997
• Status: Expired due to Fees

• Current Assignee: DENSO Corporation
• Original Assignee: DENSO Corporation
• Inventors: Elwin, Randolph G., Elmassian, Greg
• Primary Examiner(s): Bost, Dwayne D.
• Assistant Examiner(s): Gelin, Jean A.
• Application Number:
  US09/444,393
• Time in Patent Office: 358 Days
• Field of Search: 455/453, 455/404, 455/405, 455/422, 455/432, 455/434, 455/439, 455/513, 455/515, 455/524, 455/525, 455/31.2, 455/32.1, 455/446, 455/518, 455/519, 455/450, 455/452 , 455/447, 455/522, 370/322, 370/335, 370/320, 370/330
• US Class Current: 455/453
• CPC Class Codes: H04W 68/00 User notification, e.g. alerting and paging, for incoming communication, change of service or the like

Abstract

In a distributed communication system such as a personal handyphone system, when a new call must be connected through a cell station, the controller associated with the cell station checks to see if the cell station is fully loaded. If so, the controller issues a zone report request to portable telephones currently having calls connected through that cell station, and the telephones check to see if they can reconnect to a different cell station. The phones then issue a zone report to the controller indicating whether or not they are reconnectable, and one or more of the phones are directed to reconnect based on information contained in the zone reports. Consequently, a space on the target cell station is freed so that the new call can be connected. This technique is useful for incoming calls from a wireline network, outgoing calls from a portable telephone, and handoffs of a roaming portable telephone, and can also be used in an overall cell station loading management scheme.

Claims

1. A distributed communication system paging method, comprising:

receiving a call connection request;

determining whether a cell station through which said call connection request is to be routed is fully loaded;

when said cell station is determined to be fully loaded, reconnecting a reconnectable portable unit having a call connected through said cell station to a different cell station; and

connecting a call through said cell station responsive to said call connection request;

said reconnecting step comprising sending a connectivity poll command to portable units having calls connected through said cell station, and receiving a zone report from each of said portable units in response thereto, said reconnectable portable unit being one of said portable units having calls connected through said cell station, and being chosen to be reconnected based on its zone report.

2. The method of claim 1, wherein said call connection request is an incoming call request from a wireline network.

3. The method of claim 1, wherein said call connection request is an outgoing call request from a portable unit registered with said cell station.

4. The method of claim 1, wherein said call connection request is a hand-off of a roaming portable unit.

5. The method of claim 1, wherein said determining step comprises the steps of:

issuing a loading poll command to said cell station; and

determining whether a response from said cell station indicates that said cell station is fully loaded.

6. The method of claim 1, wherein said zone report received from each of said portable units during said reconnecting step indicates other cell stations with which each of said portable units is capable of establishing an alternate communication link.

7. The method of claim 1, wherein said reconnecting step further comprises the steps of:

receiving a response from said reconnectable portable unit which indicates that said reconnectable portable unit can connect to a different cell station; and

sending said reconnectable portable unit a reconnect command to cause said reconnectable portable unit to reconnect to said different cell station.

18. The method of claim 1, further comprising the step of selecting said reconnectable portable unit based on call durations associated with each of said portable units having calls connected through said cell station.

21. The method of claim 1, further comprising automatically dropping a call connected through the fully loaded cell station when the call includes a priority indicator.

22. The method of claim 21, wherein the automatic dropping of a call connected through the fully loaded cell station is based on a predetermined call parameter.

8. A personal communication system network controller comprising:

call connection request receiving means for receiving a call connection request;

cell station loading monitoring means for determining loading of a cell station through which a call corresponding to said call connection request is to be connected;

portable unit connectivity monitoring means for determining connectivity of portable units having calls connected through said cell station; and

reconnection means for directing reconnection of a reconnectable portable unit determined by said portable unit connectivity monitoring means to be reconnectable to a different cell station;

wherein said reconnection means comprises connectivity poll command sending means for sending a connectivity poll command to portable units having calls connected through said cell station, and receiving a zone report from each of said portable units, said reconnectable portable unit being one of said portable units having calls connected through said cell station, and being chosen based on its zone report.

9. The system network controller of claim 8, wherein said cell station loading monitoring means comprises:

loading poll command issuing means for issuing a loading poll command to said cell station; and

response determination means for determining whether a response from said cell station indicates that said cell station is fully loaded.

10. The system network controller of claim 8, wherein said zone report received from each of said portable units indicates other cell stations with which each of said portable units is capable of establishing an alternate communication link.

11. The system network controller of claim 8, wherein said reconnection means further comprises:

connectivity response receiving means for receiving a response from said reconnectable portable unit which indicates that said reconnectable portable unit can connect to a different cell station; and

reconnect command sending means for sending said reconnectable portable unit a reconnect command to cause said reconnectable portable unit to reconnect to said different cell station.

19. The controller of claim 8, wherein said reconnection means directs reconnection of said reconnectable portable unit based on a length of time the reconnectable portable unit has been connected to said cell station.

12. A cell station for a cellular telephone system, said station comprising:

call connection means for establishing a telephone call between a PCS unit and a PCS network controller;

call connection request receiving means for receiving a call connection request from said PCS unit; and

call connection request sending means for notifying said PCS network controller of receipt of said call connection request;

loading poll command receiving means for receiving a loading poll command signal from said PCS network controller; and

loading poll transmitting means for transmitting a loading response signal to said PCS network controller based on zone reports received from connected PCS units.

13. A personal communication system comprising:

a network controller;

a plurality of cell stations connected to said network controller; and

a plurality of portable phones each connectable to one of said cell stations;

wherein said network controller is for monitoring connection states between said cell stations and said portable phones to control the connection states thereof and for intermediating incoming calls, outgoing calls, and roaming connection requests through the cell stations and said portable phones, said network controller providing, through a given cell station, a reconnect message to each portable phone connected to said given cell station when said given cell station is fully loaded and connection is requested thereto by a portable phone presently unconnected thereto, by polling said each portable phone for reconnection determination purposes, and;

said plurality of cell stations are each for connecting to the portable phones via wireless links, transmitting connection requests from the portable phones to the network controller, and reconnecting the portable phones responsive to reception of a reconnect message from said network controller; and

said plurality of portable phones are each for providing a connection request to cell stations to which said phone is communicable other than a cell station to which said phone is presently connected, and for reconnecting to one of said cell stations which is connectable to reduce the full loading of the cell station to which said phone is presently connected when said portable phone generates a report indicative of its reconnectability to at least one of said cell stations, and as a result receives said reconnect message.

14. The system of claim 13, wherein each of said plurality of cell stations is connected to said network controller via a wired ISDN line.

15. The system of claim 13, wherein:

each of said cell stations is connectable to a limited number of portable phones;

each of said portable phones is further for requesting connection to a fully loaded cell station when said phone cannot connect to any other cell station; and

said network controller includes means for reconnecting a portable phone connected to said fully loaded cell station to another cell station so that said portable phone which cannot connect to any other cell station can connect to said fully loaded cell station.

16. The system of claim 15, wherein said portable phone which cannot connect to any other cell station is a roaming portable phone to be connected to the full loaded cell station.

17. The system of claim 13, wherein said network controller includes means for providing a reconnect message to portable phones connected to a fully loaded cell station responsive to an incoming call from said external network for a portable phone connectable to said fully loaded cell.

20. The system of claim 13, wherein said plurality of portable phones are further for reconnecting to one of said cell stations based on a call duration associated with each of said plurality of portable phones.

23. A method of managing cell station loading in a distributed communication system, comprising:

checking loading of at least one cell station within a communication zone;

determining whether the at least one cell station is fully loaded;

when the at least one cell station is determined to be fully loaded, sending a connectivity poll command to all portable units having calls connected through the cell station;

receiving a zone information report from each of the portable units in response thereto; and

reconnecting a reconnectable portable unit having a call connected through the cell station to a different cell station, the reconnectable portable unit being chosen based on its zone information report.

24. The method of claim 23, wherein the checking loading of at least one cell station within a communication zone is performed periodically to dynamically manage loading of all cell stations within the communication zone to maintain the cell stations at a less than fully loaded status.

25. The method of claim 23, further comprising identifying a location of all portable units within the communication zone through respective zone reports from each of the portable units.

26. A personal communications system portable unit cell station query method, comprising:

receiving a zone report request;

tuning to a system broadcast channel;

synchronizing with a start of a broadcast frame of a cell station;

determining parameters of the broadcast frame;

repeating the synchronizing and determining for subsequent broadcasting cell stations; and

generating a zone report when all cell stations broadcasting on the system broadcast zone have broadcast frame information.

27. The method of claim 26, wherein the determining parameters of the broadcast frame comprises determining a broadcast level of the cell station, and receiving cell station identifying information from the cell station.

28. The method of claim 26, wherein the repeating of the synchronizing and determining for subsequent broadcasting cell stations is performed only for a predetermined number of cell stations.