Patent ID: 8538322
Filing Date: 2013-09-17
Classification: H04B,H04W

Abstract:
1. A method for operating a hub in a satellite based wireless telecommunications system comprising the steps of: a) processing a set of data messages transmitted by a set of terminals by way of the satellite; b) calculating a maximum persistence that is transmitted to at least a subset of said set of terminals comprising measuring a number of message transmission attempts received during a time window for an admission group and decreasing said maximum persistence if a load ratio is greater than a high load limit and increasing the maximum persistence if the load ratio is less than a low load; c) calculating a power step value that is transmitted to a terminal from said set of terminals, comprising measuring a last message received from each terminal and a number of concurrently transmitting terminals; d) selecting a persistence for each terminal wherein the selected persistence is less that the maximum persistence; and e) performing admission and transmit power control by causing adjusting of a transmit power for each terminal based on the calculated power step value and each terminal to transmit at the selected persistence and adjusted transmit power in accordance with a predetermined procedure.