Wireless system enabling mobile-to-mobile communication

• US 6,415,146 B1
• Filed: 05/25/1999
• Issued: 07/02/2002
• Est. Priority Date: 05/25/1999
• Status: Expired due to Term

• Current Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Original Assignee: Lucent Technologies, Inc. (Nokia Corporation)
• Inventors: Capece, Christopher J.
• Primary Examiner(s): Bost, Dwayne
• Assistant Examiner(s): Trinh, Sonny
• Application Number:
  US09/317,971
• Time in Patent Office: 1,134 Days
• Field of Search: 455/426, 455/524, 455/420, 455/68, 455/20, 455/88, 455/418, 455/419, 455/515, 455/422, 455/456, 455/450, 455/525, 455/517, 370/337, 370/330, 370/344, 370/347
• US Class Current: 455/517
• CPC Class Codes: H04W 36/08 Reselecting an access point
• CPC Class Codes: H04W 4/24 Accounting or billing
• CPC Class Codes: H04W 76/10 Connection setup
• CPC Class Codes: H04W 88/02 Terminal devices
• CPC Class Codes: H04W 88/08 Access point devices
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

A wireless communications system and method, as well as a dual personality mobile, enable direct communication between subscribers of a wireless communications network. During a call between mobiles, which are suitably situated for direct communication, one mobile assumes a base station personality to establish a mobile-to-mobile traffic link. During a base station emulating mode, the mobile receives/transmits traffic signals at frequencies in the base station receive/transmit band. At least one of the. mobiles monitors the quality of the mobile-to-mobile traffic link, and reports such quality measurements back to a serving base station. When the quality measurements received by the serving base station indicate that the mobile-to-mobile traffic link has deteriorated below an acceptable threshold, the base station emulating mobile is instructed to hand off traffic transmission to the serving base station and resume normal operation. During mobile-to-mobile communication, the base station emulating mobile continues to receive/transmit control information from/to the serving base station. Therefore, the serving base station maintains control over the call, and preserves billing information.

Claims

1. A communication method comprising:

determining whether a first mobile phone and a second mobile phone of a wireless communications network, which each communicate with a base station during normal operation by transmitting at a frequency in a first frequency band and receiving at a frequency in a second frequency band that is separate from said first frequency band, are suitably situated for direct communication, the first mobile phone and the second mobile phone being suitably situated for direct communication when located in adjacent cells and in close enough proximity to achieve acceptable communication quality; and

instructing the first mobile phone to assume a base station personality when said determining step indicates that the first mobile phone and the second mobile phone are suitably situated for direct communication.

2. The method of claim 1, wherein said determining step includes:

instructing one or both of the first mobile phone and the second mobile phone to monitor control information transmitted by the other mobile phone; and

judging whether the quality of the monitored control information indicates that an acceptable mobile-to-mobile traffic link between the first mobile and the second mobile can be established.

3. The method of claim 1, further comprising:

monitoring the quality of a mobile-to-mobile traffic link after the first mobile phone has assumed the base station personality; and

instructing the first mobile to assume a normal mobile phone personality when said monitoring step indicates that the quality of the mobile-to-mobile traffic link has deteriorated below a threshold.

4. The method of claim 1, wherein:

the first mobile phone transmits/receives traffic signals at a base station transmit/receive frequency after assuming the base station personality; and

the first mobile phone transmits/receives controls signals at a mobile transmit/receive frequency after assuming the base station personality.

5. A communication system comprising:

determining means for determining whether a first mobile phone and a second mobile phone of a wireless communications network, which each communicate with a base station during normal operation by transmitting at a frequency in a first frequency band and receiving at a frequency in a second frequency band that is separate from said first frequency band, are suitably situated for direct communication, the first mobile phone and the second mobile phone being suitably situated for direct communication when located in adjacent cells and in close enough proximity to achieve acceptable communication quality; and

instructing means for instructing the first mobile phone to assume a base station personality when said determining means indicates that the first mobile phone and the second mobile phone are suitably situated for direct communication.

6. The system of claim 5, wherein said determining means includes:

means for instructing one or both of the first mobile phone and the second mobile phone to monitor control information transmitted by the other mobile phone; and

means for judging whether the quality of the monitored control information indicates that an acceptable mobile-to-mobile traffic link between the first mobile and the second mobile can be established.

7. The system of claim 5, further comprising:

monitoring means for monitoring the quality of a mobile-to-mobile traffic link after the first mobile phone has assumed the base station personality; and

means for instructing the first mobile to assume a normal mobile phone personality when said monitoring means indicates that the quality of the mobile-to-mobile traffic link has deteriorated below a threshold.

8. The system of claim 5, wherein:

the first mobile phone transmits/receives traffic signals at a base station transmit/receive frequency after assuming the base station personality; and

the first mobile phone transmits/receives controls signals at a mobile transmit/receive frequency after assuming the base station personality.

9. A mobile phone of a wireless communications network:

a dual-personality receiver. for receiving at a frequency in a first frequency band during a normal operating mode, and for receiving at a frequency in a second frequency band, which is different than said first frequency band, during a base station emulating mode; and

a dual-personality transmitter for transmitting at a frequency in the second frequency band during the normal operating mode, and for transmitting at a frequency in the first frequency band during the base station emulating mode, said mobile phone operating in said base station emulating mode to directly communicate with another mobile phone that is located in an adjacent cell of said wireless communications network and is in close enough proximity to achieve acceptable communication quality.

10. The mobile phone of claim 9, wherein

said dual personality receiver receives traffic signals from a second mobile phone at a frequency in the second frequency band during the base station emulating mode, and receives control signals from a base station at a frequency in the first frequency band during the base station emulating mode; and

said dual personality transmitter transmits traffic signals at a frequency in the first frequency band during the base station emulating mode, and transmits control signals to a base station at a frequency in the second frequency band during the base station emulating mode.

11. The mobile phone of claim 9, wherein said dual personality transmitter includes:

a transmit personality controller for controlling a generated carrier signal frequency based on whether said mobile phone is in the base station emulating mode or the normal operating mode.

12. The mobile phone of claim 9, wherein said dual personality receiver includes:

a receive personality controller for controlling a generated local oscillating signal frequency based on whether said mobile phone is in the base station emulating mode or the normal operating mode.

13. The mobile phone of claim 9, wherein said mobile phone initiates and terminates the base station emulating mode in accordance with control information received from a serving base station.

14. The mobile phone of claim 13, wherein

said mobile phone makes mobile-to-mobile traffic link quality measurements during the base station emulating mode, and reports the link quality measurements to the serving base station.

15. The mobile phone of claim 14, wherein said mobile phone hands off traffic transmission to the serving base station when instructed by the serving base station.

16. The mobile phone of claim 15, wherein the serving base station instructs said mobile to hand traffic transmission to the serving base station when the reported traffic link quality measurements drop below a threshold.