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Group TDMA frame allocation method and apparatus


A Group TDMA multiple destination, multiple node wireless network includes a first destination having a first group of nodes (Group 1) in communication range and a second destination having a second group of nodes (Group 2) in communication range. A third group of nodes (Group 3) are within communication range of both first and second destinations. Each group of nodes is assigned a periodically recurring set of time slots for transmitting to a designated destination. A network processor is programmed for (a) dividing the frame into a number of fixed-length time slots; (b) assigning a fraction 1-x of the time slots to the first and second groups of nodes; (c) assigning a fraction x of the time slots to the third group; (d) subdividing the third group into a fourth group of nodes and a fifth group of nodes; (e) assigning a fraction y of the fraction x time slots to the fourth group for transmission to the first destination and a fraction 1-y of the fraction x time slots to the fifth group for transmission to the second destination; (f) applying a multiple-access protocol to each group in its assigned set of time slots; and (g) optimizing the values of x and y in order to realize the maximum possible value of stable throughput rate .lamda.*. Group TDMA provides increased throughput capacity as it provides a balance between scheduled access and pure random access. Nodes may be grouped according to geographical location as well as arbitrary criteria, such as priority or node mission.


Gam Nguyen
Jeffrey Wieselthier

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