Patent ID: 8165097
Filing Date: 2012-04-24
Classification: H04B,H04L,H04W

Abstract:
1. A transmission method performed by a mobile station of obtaining random access diversity, the method comprising: (a) processing the signal of a random access channel (RACH) burst according to a beam forming pattern set from among a plurality of beam forming patterns, and then, transmitting the RACH burst to a base station with a first transmission power through multiple transmission antennas; (b) if a non-acknowledgement (NACK) response to the RACH burst from the base station is received, newly setting a beam forming pattern which is different from the set beam forming pattern, to a new RACH burst, and then, returning to the step (a); and (c) if an acknowledgement (ACK) response to the RACH burst is received from the base station, transmitting user packet data in response to the received ACK response using the same beam forming pattern set used to transmit the RACH burst, wherein the user packet data transmitted in response to the received ACK response is transmitted with a transmission power determined based on at least one of a structure of a preamble of the RACH burst, a modulation scheme, a coding scheme, and a size of preamble of the packet data, and wherein the transmission power is determined in the mobile station according to the first transmission power, first and second estimated signal-to-noise ratio values respectively required for the RACH burst and the user packet data to be received successfully, and a marginal power accounting for any changes in channel characteristics.