Patent ID: 8369300
Filing Date: 2013-02-05
Classification: H04B,H04L

Abstract:
1. A packet data transmission method of a mobile station including a plurality of antennas, in an orthogonal frequency division multiplex access (OFDMA) system, the packet data transmission method comprising: (a) generating a first random access channel (RACH) burst for channel information estimation; (b) selecting a first antenna among the plurality of antennas and transmitting the first RACH burst to a base station through the first antenna; (c) receiving a signal including information on whether the base station allows or does not allow data transmission, in response to the first RACH burst; and (d) when the received signal includes information indicating the base station allows data transmission, transmitting user packet data through the first antenna used for transmitting the first RACH burst, wherein when the received signal includes information indicating the base station does not allow data transmission, selecting in the mobile station a second antenna that is different from the first antenna and transmitting a second RACH burst through the second antenna, wherein in (d), when the signal including information indicating the base station allows data transmission is received, transmitting the user packet data by using the sub-band which was used for transmitting the last RACH burst.