6. Initial access mechanism

6.1 General principle

A terminal without an established radio connection must perform random access. Transmission opportunities are periodically offered to the terminal. These consist of slots on a multiple of 12 resource blocks on which any terminal can transmit a preamble. This preamble is defined in such a way as to be easily detectable by the base station.

When the base station detects a preamble, it allocates resource on the uplink channel and assigns a Temporary Cell Radio Network Temporary Identifier (TC-RNTI) to the terminal. The terminal sends a connection request message back to the network, containing an identity specific to the terminal. The network echoes this identity back. If the identities match, this assures the terminal that it is the only...