Group call management through receive/transmit synchronization

• US 7,366,532 B2
• Filed: 10/09/2003
• Issued: 04/29/2008
• Est. Priority Date: 10/09/2003
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: Miller, Jianping W., Liu, Bin, Khawand, Charbel
• Primary Examiner(s): Trinh; Tan
• Application Number:
  US10/682,772
• Publication Number:
  US 20050079883A1
• Time in Patent Office: 1,664 Days
• Field of Search: 455/502, 455/416, 455/415, 455/13.2, 455/518, 455/519, 455/446, 455/500, 455/434, 455/71, 455/88, 370/310, 370/337, 370/343
• US Class Current: 455/502
• CPC Class Codes: H04B 7/269 Master/slave synchronisation
• CPC Class Codes: H04W 56/002 Mutual synchronization
• CPC Class Codes: H04W 56/0035 detecting errors in frequency or phase
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

A method of communicating with a transceiver (120). In one arrangement, the method of communicating with the transceiver can be performed in a systemless group environment. Synchronization information (150) can be received from a mobile transceiver (110) and used to synchronize to the mobile transceiver. The synchronization information can include a timing offset and a frequency offset. Synchronization can be maintained until a predetermined condition is met, for example, a predetermined amount of group inactivity.

Claims

1. A method of communicating with a transceiver comprising the steps of:

in a systemless group environment, receiving synchronization information from a mobile transceiver that is part of a group;

synchronizing to the mobile transceiver using the synchronization information; and

maintaining synchronization with the mobile transceiver until no group activity has been detected for a predetermined time period following the termination of a transmission within the group such that if another device in the group begins transmitting before the predetermined time period expires, the group maintains the established synchronization until another period of group inactivity is detected that exceeds the predetermined amount of time.

2. The method according to claim 1, wherein said receiving synchronization information step comprises receiving a timing offset and a frequency offset.

3. The method according to claim 1, further comprising the step of transmitting a transmission request comprising a preamble, the transmission request being transmitted in a time slot synchronized with the mobile transceiver.

4. The method according to claim 3, wherein the transmission request further comprises synchronization information.

5. The method according to claim 3, further comprising the step of randomly selecting the synchronized time slot.

6. A method of communicating with a transceiver comprising the steps of:

in a systemless group environment, transmitting synchronization information to a plurality of transceivers, the synchronization information establishing group synchronization with the plurality of transceivers to form a group; and

maintaining synchronization with the plurality of transceivers until no group activity has been detected for a predetermined time period following the termination of a transmission within the group such that if one of the transceivers in the group begins another transmission before the predetermined time period expires, the group maintains the established synchronization until another period of group inactivity is detected that exceeds the predetermined amount of time.

7. The method according to claim 6, wherein said transmitting synchronization information step comprises transmitting a timing offset and a frequency offset.

8. The method according to claim 6, further comprising the step of:

receiving a transmission request the transmission request comprising a preamble and the transmission request being received in a synchronous time slot.

9. The method according to claim 8, wherein the transmission request further comprises synchronization information.

10. The method according to claim 6, wherein said step of transmitting synchronization information to a plurality of transceivers further comprises transmitting synchronization to a new transceiver that is part of the group.

11. A machine-readable storage, having stored thereon a computer program having a plurality of code sections executable by a machine for causing the machine to perform the steps of:

in a systemless group environment, receiving synchronization information from a mobile transceiver that is part of a group;

synchronizing to the mobile transceiver using the synchronization information; and

maintaining synchronization with the mobile transceiver until no group activity has been detected for a predetermined time period following the termination of a transmission within the group such that if another device in the group begins transmitting before the predetermined time period expires, the group maintains the established synchronization until another period of group inactivity is detected that exceeds the predetermined amount of time.

12. The machine readable storage of claim 11, further comprising the step of transmitting a transmission request comprising a preamble, the transmission request being transmitted in a time slot synchronized with the mobile transceiver.

13. A machine-readable storage, having stored thereon a computer program having a plurality of code sections executable by a machine for causing the machine to perform the steps of:

in a systemless group environment, transmitting synchronization information to a plurality of transceivers, the synchronization information establishing group synchronization with the plurality of transceivers to form a group; and

maintaining synchronization with the plurality of transceivers until no group activity has been detected for a predetermined time period following the termination of a transmission within the group such that if one of the transceivers in the group begins another transmission before the predetermined time period expires, the group maintains the established synchronization until another period of group inactivity is detected that exceeds the predetermined amount of time.