A system and method for random access channel (RACH) capture, where user equipment
(UE) transmits a series of time-spaced access preambles each having an increasing
power level to Node B and terminates access preamble transmission in response to
an acquisition indicator (AI) signal returned from Node B and transmits its RACH
message part. A collision detection preamble (CDP) is sent immediately after the
message or embedded with the message. A collision detection indicator (CDI) signal
matching the CDP is transmitted from Node B to the UE identified as having the
failed RACH message requesting retransmission of the message. Optionally, the relative
retransmission power level is also specified to the UE along with the CDI signal.
