Patent ID: 7508802
Filing Date: 2009-03-24
Classification: H04W

Abstract:
1. A method of controlling Wireless Local Area Network (WLAN) medium access using Pseudo-Time Division Multiplexing (PTDM) to improve Quality of Service (QoS) of a Voice over Internet Protocol system to which a WLAN, which includes a Basic Service Set (BSS) having a plurality of Mobile Terminals (MTs) and an Access Point (AP) that are connected via a Radio Frequency (RF) link, is applied, comprising: the first step of a Mobile Terminal (MT) acquiring QoS information, which relates to a voice frame to be transmitted, from an upper layer; the second step of the MT exchanging a frame for a request to transmit the voice frame during a contention free period, including the QoS information, with the AP and being allocated QoS slot (QSLOT) information by the AP in response to the request by the MT during the contention free period; the third step of dividing an RF link section between the MT and the AP by a creation period of the voice frame (QoS frame transmission interval: QTX-INT), wherein the creation period includes a DCF Inter Frame Space before entering a contention period; the fourth step of transmitting the voice frame in the divided creation period of the voice frame using the allocated QSLOT information; and after the voice frame is transmitted, each of the plurality of MTs and the AP determining a remaining time in the creation period that is assigned to the contention period after the DCF Inter Frame Space and deferring transmission of an additional voice frame when a time required for an exchange of the additional voice frame is greater than the remaining time in the creation period after the DCF Inter Frame Space.