Cordless radiotelephone system having an extendable geographic coverage area and method therefor

• US 6,078,821 A
• Filed: 02/25/1998
• Issued: 06/20/2000
• Est. Priority Date: 02/25/1998
• Status: Expired due to Term

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Metroka, Michael Peter, Kalenowsky, John Alan, Kaschke, Kevin D.
• Primary Examiner(s): Eisenzopf, Reinhard J.
• Assistant Examiner(s): RAMOS FELICIANO, ELISEO
• Application Number:
  US09/030,663
• Time in Patent Office: 846 Days
• Field of Search: 455/507, 455/524, 455/560, 455/561, 455/436, 455/462, 455/465, 370/343, 370/216, 370/310, 370/318, 370/328, 370/331, 370/480
• US Class Current: 455/507
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 88/10 adapted for operation in multiple networks, e.g. multi-mode access points

Abstract

A cordless telephone system (300) comprises a portable station (305), a first base station (301) and a second base station (310). The first base station (301) communicates with the portable station (305) over a communication channel (441) when the portable station (305) is located within a first geographic coverage area (311). The second base station (310) communicates with the portable station (305) over a communication channel (441) when the portable station (305) is located within a second geographic coverage area (313). The first base station (301) includes a controller (302) adaptively configured to be a master controller (302). The second base station (310) includes a controller (308) configured to be slave controller (308) responsive to the controller (302) of the first base station (301) being adaptively configured to be the master controller (302). The master controller (302) communicates with the slave controller (308) over a communication path (315) to coordinate communications between the portable station (305) and at least one of the first base station (301) and the second base station (310) when the portable station (305) is located within the first geographic coverage area (311) and the second geographic coverage area (313), respectively. The cordless telephone system (300) advantageously provides an expandable geographic coverage area for a relatively low cost when the number of portable stations are relatively small and the communication traffic is relatively low.

Claims

1. An extendable cordless telephone system including a first base station covering a first geographic area and having a first controller, the first base station for communicating with at least one portable station when the at least one portable station is located within the first geographic area, the extendable cordless telephone system comprising:

a second base station covering a second geographic coverage area and having a second controller;

the first base station to determine whether any of the first base station and the second base station is coupled to a public switched telephone network (PSTN) and to determine whether the second base station is coupled to the cordless telephone system;

wherein when it is determined that the first base station is coupled to the PSTN and the second base station is not coupled to the cordless telephone system, the first controller is adapted to act as a master controller to coordinate communications between the at least one portable station and the first base station when the at least one portable station is within the first geographic coverage area, and

when it is determined that the first base station is coupled to the PSTN and the second base station is coupled to the cordless telephone system and the PSTN, the first controller is adapted to act as the master controller and the second controller is adapted to act as a slave controller, wherein the slave controller is adapted to communicate with the master controller over a communication path to coordinate communications between the at least one portable station and the first base station when the at least one portable station is within the first geographic area and the second base station when the at least one portable station is within the second geographic area.

2. A cordless telephone system according to claim 1 wherein the communication path is a radio frequency channel.

3. A cordless telephone system according to claim 1 wherein the communication path is a telephone wireline of the public switched telephone network.

4. A cordless telephone system according to claim 1 wherein the communication path is an alternating current power supply line.

5. A cordless telephone system according to claim 1 wherein the communication path is a dedicated, direct wireline.

6. A cordless telephone system according to claim 1 wherein the first geographic coverage area at least partially overlaps the second geographic coverage area.

7. A cordless telephone system according to claim 1 wherein the first geographic coverage area does not overlap the second geographic coverage area.

8. A cordless telephone system according to claim 1 wherein the cordless telephone system reconfigures itself responsive to an occurrence of a predetermined condition.

9. A cordless telephone system according to claim 8 wherein the occurrence of the predetermined condition further comprises an expiration of a random time.

10. A cordless telephone system according to claim 8 wherein the occurrence of the predetermined condition further comprises an expiration of a predetermined time.

11. A cordless telephone system according to claim 8 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being temporarily disconnected from a power source.

12. A cordless telephone system according to claim 8 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being disconnected from the cordless telephone system.

13. A method for extending a cordless telephone system including a first base station, having a first controller, for communicating with at least one portable station over a communication channel when the at least one portable station is located within a first geographic coverage area, the method, performed by the first base station, comprising the steps of:

a) determining whether a second base station is coupled to the cordless telephone system, wherein the second base station, having a second controller, is adapted to communicate with the at least one portable station over a communication channel when the at least one portable station is within a second geographic coverage area;

b) determining whether the second base station is coupled to a public switched telephone network;

c) determining whether the first base station is coupled to the public switched telephone network;

d) configuring the first controller of the first base station as a master controller responsive to determining that the second base station is not coupled to the cordless telephone system and responsive to determining that the first base station is coupled to a public switched telephone network, wherein the master controller of the first base station is adapted to coordinate communications between the at least one portable station and the first base station when the at least one portable station is located within the first geographic coverage area; and

e) configuring the first controller of the first base station as a slave controller responsive to determining that the second base station is coupled to the cordless telephone system and responsive to determining that the second base station is coupled to the public switched telephone network, wherein the second controller of the second base station is configured as a master controller, wherein the slave controller of the first base station is adapted to communicate with the master controller of the second base station over a communication path to coordinate communications between the portable handset and at least one of the first base station and the second base station within the first geographic coverage area and the second geographic coverage area, respectively.

14. A method according to claim 13 wherein the communication path is a radio frequency channel.

15. A method according to claim 13 wherein the communication path is a telephone line of the public switched telephone network.

16. A method according to claim 13 wherein the communication path is an alternating current power supply line.

17. A method according to claim 13 wherein the communication path is a dedicated, direct line connection.

18. A method according to claim 13 wherein the first geographic coverage area at least partially overlaps the second geographic coverage area.

19. A method according to claim 13 wherein the first geographic coverage area does not overlap the second geographic coverage area.

20. A method according to claim 13 further comprising the steps of:

detecting an occurrence of a predetermined condition responsive to the first controller of the first base station being configured as one of the master controller and the slave controller; and

repeating the steps a) through e) responsive to the occurrence of the predetermined condition.

21. A method according to claim 20 wherein the occurrence of the predetermined condition further comprises an expiration of a random time.

22. A method according to claim 20 wherein the occurrence of the predetermined condition further comprises an expiration of a predetermined time.

23. A method according to claim 20 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being temporarily disconnected from a power source.

24. A method according to claim 20 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being disconnected from the cordless telephone system.

25. A method according to claim 13 further comprising the steps of:

determining whether the first base station is within the second geographic coverage area of the second base station; and

determining whether the second base station is within the first geographic coverage area of the first base station.

26. A method according to claim 25:

wherein the step of determining whether the first base station is within the second geographic coverage area of the second base station further comprising the steps of;

transmitting a first signal by the first base station; and

receiving the first signal by the second base station; and

wherein the step of determining whether the second base station is within the first geographic coverage area of the first base station further comprising the steps of;

transmitting a second signal by the second base station responsive to receiving the first signal; and

receiving the second signal by the first base station.

27. A method according to claim 13 further comprising the steps of:

assigning a system security code to at least the first base unit responsive to the first controller of the first base station being configured as the master controller.

28. A method according to claim 13 further comprising the steps of:

exchanging data between the first base station and the second base station responsive to the first controller of the first base station being configured as the slave controller.

29. A method according to claim 13 further comprising the steps of:

repeating steps a), b) and c) responsive to determining that the second base station is not coupled to the cordless telephone system and responsive to determining that the first base station is not coupled to a public switched telephone network.

30. A method for extending a cordless telephone system including a first base station, having a first controller, for communicating with at least one portable station over a communication channel when the at least one portable station is located within a first geographic coverage area, the method, performed by the first base station, comprising the steps of:

a) determining whether a second base station is coupled to the cordless telephone system, wherein the second base station, having a second controller, is adapted to communicate with the at least one portable station over a communication channel when the at least one portable station is within a second geographic coverage area;

b) determining whether the second base station is coupled to a public switched telephone network;

c) determining whether the first base station is coupled to the public switched telephone network;

d) configuring the first controller of the first base station as a master controller responsive to determining that the second base station is not coupled to the cordless telephone system and responsive to determining that the first base station is coupled to a public switched telephone network, wherein the master controller of the first base station is adapted to coordinate communications between the at least one portable station and the first base station when the at least one portable station is located within the first geographic coverage area; and

e) configuring the first controller of the first base station as a slave controller responsive to determining that the second base station is coupled to the cordless telephone system and responsive to determining that the second base station is coupled to the public switched telephone network, wherein the second controller of the second base station is configured as a master controller, wherein the slave controller of the first base station is adapted to communicate with the master controller of the second base station over a communication path to coordinate communications between the portable handset and at least one of the first base station and the second base station within the first geographic coverage area and the second geographic coverage area, respectively;

f) repeating steps a), b) and c) responsive to determining that the second base station is not coupled to the cordless telephone system and responsive to determining that the first base station is not coupled to a public switched telephone network;

g) detecting an occurrence of a predetermined condition responsive to the first controller of the first base station being configured as one of the master controller and the slave controller; and

h) repeating the steps a) through f) responsive to the occurrence of the predetermined condition.

31. A method according to claim 30 wherein the communication path is a radio frequency channel.

32. A method according to claim 30 wherein the communication path is a telephone line of the public switched telephone network.

33. A method according to claim 30 wherein the communication path is an alternating current power supply line.

34. A method according to claim 30 wherein the communication path is a dedicated, direct line connection.

35. A method according to claim 30 wherein the first geographic coverage area at least partially overlaps the second geographic coverage area.

36. A method according to claim 30 wherein the first geographic coverage area does not overlap the second geographic coverage area.

37. A method according to claim 30 wherein the occurrence of the predetermined condition further comprises an expiration of a random time.

38. A method according to claim 30 wherein the occurrence of the predetermined condition further comprises an expiration of a predetermined time.

39. A method according to claim 30 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being temporarily disconnected from a power source.

40. A method according to claim 30 wherein the occurrence of the predetermined condition further comprises at least one of the first base station and the second base station being disconnected from the cordless telephone system.

41. A method according to claim 30 further comprising the steps of:

determining whether the first base station is within the second geographic coverage area of the second base station; and

determining whether the second base station is within the first geographic coverage area of the first base station.

42. A method according to claim 41:

wherein the step of determining whether the first base station is within the second geographic coverage area of the second base station further comprising the steps of;

transmitting a first signal by the first base station; and

receiving the first signal by the second base station; and

wherein the step of determining whether the second base station is within the first geographic coverage area of the first base station further comprising the steps of;

transmitting a second signal by the second base station responsive to receiving the first signal; and

receiving the second signal by the first base station.

43. A method according to claim 30 further comprising the steps of:

assigning a system security code to at least the first base unit responsive to the first controller of the first base station being configured as the master controller.

44. A method according to claim 30 further comprising the steps of:

exchanging data between the first base station and the second base station responsive to the first controller of the first base station being configured as the slave controller.