Patent ID: 7289804
Filing Date: 2007-10-30
Classification: H04W,Y02D

Abstract:
1. A method for establishing by a subscriber station a sleep interval of a sleep mode in a communication system, the method comprising the steps of: a first step of repeating an operation for maintaining the sleep mode during a sleep interval corresponding to a window value and then shifting into an awake mode so as to receive a traffic indication message from a base station, while changing a present sleep interval to have a value larger than that of a previous sleep interval within a range from a minimum window value to a maximum window value so long as a positive traffic indication message is not received; a second step of exponentially increasing the minimum window value if the positive traffic indication message is not received until the window value becomes the maximum window value in the first step; a third step of returning to the first step if the increasing minimum window value belongs to a range of the maximum window value in the second step; a fourth step of, if the increasing minimum window value is greater than the maximum window value in the second step, repeating an operation for maintaining the sleep mode during a sleep interval corresponding to a present minimum window value and then shifting into the awake mode so as to receive the traffic indication message from the base station, so long as the positive traffic indication message is not received; and a fifth step of receiving data from the base station if the positive traffic indication message is received in the first step or the fourth step.