Patent ID: 8693448

Claim:
A method of random access, the method comprising: transmitting, by a higher layer, an indicator to a lower layer, indicating to the lower layer to transmit a random access preamble, wherein the indicator includes a cause value indicating a cause of transmission of the random access preamble; and transmitting, by the lower layer, the random access preamble, wherein: when the cause value indicates re-transmission due to a received random access response not corresponding to a previously transmitted random access preamble, the random access preamble is transmitted no later than in a subframe (n+5), wherein the subframe n is the subframe in which the random access response is received; or when the cause value indicates re-transmission due to no random access response being received in response to a previously transmitted random access preamble, the random access preamble is transmitted no later than in a subframe (n+4), wherein the subframe n is the last subframe of the random access response window.