OFDMA contention-based random access channel design for mobile wireless systems

摘要

Short spreading is used within a random access channel in an OFDM based network to spread data for transmission through the channel. The resource allocation of the random access channel is divided into a number of resource blocks in frequency, time, or both frequency and time. Each resource block has a dimension that is only a portion of the overall size of the resource allocation. During contention, a randomly selected short spreading code may be used to provide data spreading within a randomly selected resource block.