US Patent 8964659 Random access channel resource allocation

The present invention provides a method of configuring random access resources for random access transmission, the method comprising: determining a number n of preamble signatures that can be used for random access transmission; grouping the n preamble signatures into K groups j (j=1, 2K) wherein K corresponds to a number of downlink component carriers and K is greater than or equal to 2; assigning each group j to a respective downlink component carrier; assigning configuration data to each group j; and transmitting the group j configuration data on the corresponding downlink component carrier.