Methods and apparatus for vertical beamforming

Abstract

A method and apparatus for determining a vertical beam for reception are disclosed herein. A method in a wireless transmit/receive unit (WTRU) includes receiving a broadcast message from an evolved Node B (eNB) that includes information associated with a plurality of vertical beams, wherein the information includes at least one set of Physical Random Access Control Channel (PRACH) resources associated with each of the plurality of vertical beams, measuring reference signals transmitted on each of the plurality of vertical beams to select a reception vertical beam, transmitting a PRACH preamble in a set of resources associated with the selected reception vertical beam, and receiving communications from the eNB using the selected reception vertical beam.

1 . A method for determining a vertical beam for reception in a wireless transmit/receive unit (WTRU), the method comprising:
 receiving a broadcast message from an evolved Node B (eNB) that includes information associated with a plurality of vertical beams, wherein the information includes at least one set of Physical Random Access Control Channel (PRACH) resources associated with each of the plurality of vertical beams;   measuring reference signals transmitted on each of the plurality of vertical beams to select a reception vertical beam;   transmitting a PRACH preamble in a set of resources associated with the selected reception vertical beam; and   receiving communications from the eNB using the selected reception vertical beam.   
     
     
         2 . The method of  claim 1 , wherein the information associated with the plurality of vertical beams includes a plurality of measurement configurations. 
     
     
         3 . The method of  claim 1 , wherein the PRACH preamble is transmitted on an allocated frequency associated with the set of resources. 
     
     
         4 . The method of  claim 1 , wherein the WTRU selects a reception vertical beam based on a determination that the measured reference signal is better on at least one vertical beam. 
     
     
         5 . The method of  claim 1 , wherein the WTRU selects a reception vertical beam based on predetermined criteria. 
     
     
         6 . The method of  claim 1 , wherein the at least one set of PRACH resources is portioned based on the number of the plurality of vertical beams. 
     
     
         7 . A wireless transmit/receive unit (WTRU) for determining a vertical beam for reception comprising:
 a receiver configured to receive a broadcast message from an evolved Node B (eNB) that includes information associated with a plurality of vertical beams, wherein the information includes at least one set of Physical Random Access Control Channel (PRACH) resource associated with each of the plurality of vertical beams;   a processor configured to measure reference signals transmitted on each of the plurality of vertical beams to select a reception vertical beam;   a transmitter configured to transmit a PRACH preamble in a set of resources associated with the selected reception vertical beam; and   the receiver is further configured to receive communications from the eNB using the selected reception vertical beam.   
     
     
         8 . The WTRU of  claim 7 , wherein the information associated with the plurality of vertical beams includes a plurality of measurement configurations. 
     
     
         9 . The WTRU of  claim 7 , wherein the PRACH preamble is transmitted on an allocated frequency associated with the set of resources. 
     
     
         10 . The WTRU of  claim 7 , wherein the WTRU selects a reception vertical beam based on a determination that the measured reference signal is better on at least one vertical beam. 
     
     
         11 . The WTRU of  claim 7 , wherein the WTRU selects a reception vertical beam based on predetermined criteria. 
     
     
         12 . The WTRU of  claim 7 , wherein the at least one set of PRACH resources is portioned based on the number of the plurality of vertical beams. 
     
     
         13 . A method for determining a vertical beam for reception in an evolved Node B (eNB), the method comprising:
 transmitting a broadcast message to a wireless transmit/receive unit (WTRU) that includes information associated with a plurality of vertical beams, wherein the information includes at least one set of Physical Random Access Control Channel (PRACH) resources associated with each of the plurality of vertical beams;   receiving a PRACH preamble in a set of resources associated with a selected reception vertical beam, wherein the selected reception vertical beam is determined by the WTRU based on measured reference signals transmitted on each of the plurality of vertical beams; and   transmitting communications to the WTRU using the selected reception vertical beam.   
     
     
         14 . The method of  claim 13 , wherein the information associated with the plurality of vertical beams includes a plurality of measurement configurations. 
     
     
         15 . The method of  claim 13 , wherein the PRACH preamble is transmitted on an allocated frequency associated with the set of resources. 
     
     
         16 . The method of  claim 13 , wherein the selection of a reception vertical beam is based on a determination that the measured reference signal is better on at least one vertical beam. 
     
     
         17 . The method of  claim 13 , wherein the selecting of a reception vertical beam is based on predetermined criteria. 
     
     
         18 . The method of  claim 13 , wherein the at least one set of PRACH resources is portioned based on the number of the plurality of vertical beams. 
     
     
         19 . A method for determining a vertical beam for transmission in an evolved Node B (eNB), the method comprising:
 transmitting a broadcast message to a wireless transmit/receive unit (WTRU) that includes two or more Channel State Information-Reference Signal (CSI-RS) configurations;   receiving a first measurement report from the WTRU including a received signal-to-interference plus noise ratio (SINR) for a cell-specific CSI-RS in an uplink subframe;   receiving a second measurement report from the WTRU including SINR for each antenna port in the cell-specific CSI-RS associated with a vertical beam; and   transmitting communications to the WTRU using vertical beam.