ORTHOGONAL FREQUENCY DIVISION MULTIPLEXING ACCESS-TIME DIVISION DUPLEXING SYSTEM AND COMPENSATING METHOD OF PACKET TRANSMISSION TIME

摘要

An OFDMA-TDD(Orthogonal Frequency Division Multiplexing Access-Time Division Duplexing) system and a method for setting a packet transmission correcting time are provided to set a correction time based on the delay time of ranging packets received in a base station modem, and the symbol time and guard time of the OFDMA-TDD system and transmit the correction time to a mobile station. A method for setting a packet transmission correcting time comprises the following steps of: confirming whether ranging is requested or not by enabling a base station to receive a message from a mobile station in a standby state(S401,S402); confirming a ranging packet arrival delay time on the basis of the received message if there is the ranging request(S403); calculating a deviation time by using the guard time of a symbol previously specified and the confirmed delay time(S404); setting a correction time for correcting the point of time for the packet transmission of the mobile station on the basis of the calculated deviation time(S405,S406,S407); and returning to the standby state after transmitting a ranging response message including correction time information to the mobile station(S408).