Keep alive timeslots in a heterogeneous MAC protocol to track handsets in a wireless network

• US 8,274,955 B2
• Filed: 05/07/2009
• Issued: 09/25/2012
• Est. Priority Date: 06/16/2008
• Status: Active Grant

• Current Assignee: Vislink Technologies, Inc.
• Original Assignee: xG Technology, Inc.
• Inventors: Gandham, Shashidhar R., Chang, Shih-Chun
• Primary Examiner(s): LI, GUANG W
• Application Number:
  US12/387,811
• Publication Number:
  US 20090310575A1
• Time in Patent Office: 1,237 Days
• Field of Search: 370/337
• US Class Current: 370/337
• CPC Class Codes: H04W 60/02 by periodical registration
• CPC Class Codes: H04W 76/25 Maintenance of established connections
• CPC Class Codes: H04W 80/02 Data link layer protocols

Abstract

This disclosure describes a new keep alive timeslots based method to track registered handsets for a MAC protocol that combines contention-free and contention-based MAC protocols into a heterogeneous MAC protocol used for forwarding VoIP traffic in VoIP systems on wireless networks using multiple base stations thus allowing for transmission of high bit-rate data to multiple users over wired and wireless means.

Claims

1. A method of scheduling of keep alive messages using keep alive timeslots in a medium access control protocol having hyperframes made up of superframes containing headers and time slots dedicated to keep alive messages used for forwarding Internet Protocol packets and keep alive messages on a communications channel between a base station and nodes in voice over the Internet protocol systems on a wired or wireless network comprising:

first a base station storing and assigning a different keep alive time slot to each node in wired or wireless communication with said base station up to a maximum number of keep alive time slots wherein said maximum number of said keep alive timeslots is less than a set maximum number of superframes within a hyperframe, which set maximum number of superframes is based on the maximum number of nodes capable of being serviced by said base station'"'"'s communications channel;

then said base station transmitting and said node receiving said assigned keep alive timeslot during an identified hyperframe number and an identified superframe number, and then said node computing a computed timeslot number based on said assigned keep alive timeslot, said identified hyperframe number, and said identified superframe number;

said node then incrementing said computed timeslot number by one for each subsequent superframe and then sending a first keep alive message during a superframe when said computed timeslot number equals said assigned keep alive timeslot;

then said node sending additional keep alive messages only during superframes that come after the number of superframes received by said node after said node'"'"'s last sent keep alive message equals the maximum number of keep alive timeslots; and

,

then some of said keep alive timeslots being used for other messages when not sending keep alive messages.

2. The method of scheduling of keep alive messages using keep alive timeslots of claim 1 wherein a control element contained in said header is used to dynamically adjust said keep alive timeslots.

3. The method of scheduling of keep alive messages using keep alive timeslots of claim 1 wherein a skipping announcement contained in said header is used to skip said keep alive timeslots that are no longer being used.