TTI bundling is included for Msg3 transmissions in LTE communications. A reserved group of preambles or reserved set of random access preamble transmission opportunities are used to indicate user equipment (UE) need of uplink (UL) transmission of a TTI-bundled Msg3. The UE transmits the same redundancy version for transmissions within a TTI bundle as the eNB expects even if any of the transmissions are dropped due to collisions with an Msg3 transmission. In addition, co-existence of TTI bundling and UL semi-persistent scheduling (SPS) for TDD DL/UL configurations is provided using SPS intervals which are multiples of various fixed time periods.