Methods and apparatus for vertical beamforming

A wireless transmit/receive unit (WTRU) for determining resources, the WTRU comprising:

• a receiver configured to receive a configuration message, wherein the configuration message is at least one of a broadcast message or a radio resource control (RRC) message, from a base station that includes correspondence information regarding a plurality of beam reference signals, wherein the correspondence information designates at least one set of Physical Random Access Channel (PRACH) resources for each of the plurality of beam reference signals;
• a processor, operatively coupled to the receiver, configured to measure the plurality of beam reference signals transmitted from the base station;
• the processor further configured to select a beam reference signal from among the plurality of measured beam references signals;
• the processor further configured to determine a set of PRACH resources designated for the selected beam reference signal based on the received correspondence information;
• and
• a transmitter, operatively coupled to the processor, the transmitter and the processor configured to transmit a PRACH signal using at least one PRACH resource of the determined set of PRACH resources.

A method for use in a wireless transmit/receive unit (WTRU) for determining resources, the method comprising:

• receiving, by the WTRU, a configuration message, wherein the configuration message is at least one of a broadcast message or a radio resource control (RRC) message, from a base station that includes correspondence information regarding a plurality of beam reference signals, wherein the correspondence information provides at least one set of Physical Random Access Channel (PRACH) preambles, wherein the set of PRACH preambles includes one or more PRACH preambles, for each of the plurality of beam reference signals;
• measuring, by the WTRU, the plurality of beam reference signals, transmitted from the base station;
• selecting, by the WTRU, a beam reference signal from among the plurality of measured beam references signals;
• determining, by the WTRU, a set of PRACH preambles designated for the selected beam reference signal based on the received correspondence information;
• and
• transmitting, by the WTRU, a PRACH preamble of the determined set of PRACH preambles.