INITIAL ACCESS IN HIGH FREQUENCY WIRELESS SYSTEMS
Methods, devices and systems are provided for performing a random access (RA) procedure. A wireless transmit/receive unit (WTRU) may be configured to receive RA resource sets, where each of the RA resource sets is associated with a node-B directional beam, select an RA resource set from among the RA resource sets, and initiate an RA procedure based on the selected RA resource set. The RA procedure may include selecting multiple preambles which include a preamble for each resource of a plurality of resources corresponding to the selected RA resource set. The WTRU may be configured to sequentially transmit the selected multiple preambles in sequential RA transmissions, and may be configured to receive, from a node-B, in response to the RA transmissions, at least one RA response (RAR), where each of the received at least one RAR corresponds to one of the transmitted multiple preambles.
1 . A wireless transmit/receive unit (WTRU) comprising:
a receiver configured to receive a plurality of random access (RA) resource sets, wherein each of the plurality of RA resource sets is associated with a node-B directional beam of a plurality of node-B directional beams, and each of the plurality of RA resource sets includes a plurality of resources;
at least one processor configured to select an RA resource set from among the plurality of RA resource sets;
the at least one processor configured to initiate an RA procedure based on the selected RA resource set, wherein the RA procedure includes determining the plurality of resources corresponding to the selected RA resource set, and selecting multiple preambles which include a preamble for each resource of the plurality of resources corresponding to the selected RA resource set; and
a transmitter configured to sequentially transmit the selected multiple preambles to a node-B in sequential RA transmissions using the plurality of resources corresponding to the selected RA resource set,
wherein the receiver and the processor are further configured to monitor for a plurality of random access responses (RARs) corresponding to the sequential RA transmissions such that monitoring for a first RAR at least partially overlaps with monitoring for a second RAR, and receive, from the node-B, in response to the sequential RA transmissions, at least one RAR, wherein each of the received at least one RAR corresponds to one of the transmitted multiple preambles.
2 . (canceled)
3 . The WTRU of claim 1 , wherein each of the received plurality of RA resource sets includes at least one preamble and resource information corresponding to at least one directional WTRU uplink (UL) transmit beam, and the RA procedure includes selecting a preamble and a directional WTRU UL transmit beam for each of the plurality of resources corresponding to the selected RA resource set.
4 . The WTRU of claim 1 , wherein the plurality of RA resource sets are associated with one node-B directional beam of the plurality of node-B directional beams.
5 . The WTRU of claim 1 , wherein each of the plurality of RA resource sets is associated with a different node-B directional beam of the plurality of node-B directional beams.
6 . The WTRU of claim 1 , wherein the transmitter is configured to sequentially transmit the selected multiple preambles to the node-B in the sequential RA transmissions using at least one directional transmit beam linked to the selected RA resource set.
7 . The WTRU of claim 1 , wherein the at least one processor is configured to select an uplink beam based on the received at least one RAR.
8 . The WTRU of claim 1 , wherein the receiver is configured to receive, from the node-B, in response to the sequential RA transmissions, the plurality of RARs,
the processor is configured to select a RAR from the plurality of RARs based on a rule, and
the at least one processor is configured to select an uplink beam based on the selected RAR.
9 . The WTRU of claim 1 , wherein each of the plurality of RA resource sets is associated with a node-B downlink (DL) transmit beam mapped to at least one node-B uplink (UL) receive beam.
10 . (canceled)
11 . The WTRU of claim 1 , wherein the plurality of node-B directional beams are node-B downlink (DL) transmit beams, and the receiver is configured to receive information representative of the plurality of node-B DL transmit beams, and the processor is configured to select the RA resource set based on the information representative of the plurality of node-B DL transmit beams.
12 . (canceled)
13 . The WTRU of claim 1 , wherein each of the received plurality of RA resource sets includes RAR window information,
the RA procedure includes determining a RAR window for each resource of the plurality of resources corresponding to the selected RA resource set, and
the receiver and the processor are further configured to monitor for the plurality of RARs based on the determined RAR window for each resource of the plurality of resources corresponding to the selected RA resource set.
14 . (canceled)
15 . A method for use by a wireless transmit/receive unit (WTRU), the method comprising:
receiving, by the WTRU, a plurality of random access (RA) resource sets, wherein each of the plurality of RA resource sets is associated with a node-B directional beam of a plurality of node-B directional beams, and each of the plurality of RA resource sets includes a plurality of resources;
selecting, by the WTRU, an RA resource set from among the plurality of RA resource sets;
initiating, by the WTRU, an RA procedure based on the selected RA resource set, wherein the RA procedure includes determining the plurality of resources corresponding to the selected RA resource set, and selecting multiple preambles which include a preamble for each resource of the plurality of resources corresponding to the selected RA resource set;
transmitting, by the WTRU, the selected multiple preambles to a node-B in sequential RA transmissions using the plurality of resources corresponding to the selected RA resource set;
monitoring for a plurality of random access responses (RARs) corresponding to the sequential RA transmissions such that monitoring for a first RAR at least partially overlaps with monitoring for a second RAR; and
receiving, by the WTRU, from the node-B in response to the sequential RA transmissions, at least one RAR, wherein each of the received at least one RAR corresponds to one of the transmitted multiple preambles.
16 . (canceled)
17 . The method of claim 15 , wherein each of the received plurality of RA resource sets includes at least one preamble and resource information corresponding to at least one directional WTRU uplink (UL) transmit beam, and the RA procedure includes selecting a preamble and a directional WTRU UL transmit beam for each of the plurality of resources corresponding to the selected RA resource set.
18 . The method of claim 15 , wherein the plurality of RA resource sets are associated with one node-B directional beam of the plurality of node-B directional beams.
19 . The method of claim 15 , wherein each of the plurality of RA resource sets is associated with a different node-B directional beam of the plurality of node-B directional beams.
20 . The method of claim 15 , wherein transmitting the selected multiple preambles further includes sequentially transmitting the selected multiple preambles to the node-B in the sequential RA transmissions using at least one directional transmit beam linked to the selected RA resource set.
21 . The method of claim 15 , further comprising:
selecting an uplink beam based on the received at least one RAR.
22 . The method of claim 15 , further comprising:
receiving, by the WTRU from the node-B in response to the sequential RA transmissions, the plurality of RARs;
selecting, by the WTRU, a RAR from the plurality of RARs based on a rule; and
selecting, by the WTRU, an uplink beam based on the selected RAR.
23 . The method of claim 15 , wherein each of the plurality of RA resource sets is associated with a node-B downlink (DL) transmit beam mapped to at least one node-B uplink (UL) receive beam.
24 . (canceled)
25 . The method of claim 15 , wherein the plurality of node-B directional beams are node-B downlink (DL) transmit beams, the method further comprising:
receiving, by the WTRU, information representative of the plurality of node-B downlink (DL) transmit beams; and
selecting, by the WTRU, the RA resource set based on the information representative of the plurality of node-B DL transmit beams.
26 . (canceled)
27 . The method of claim 15 , wherein each of the received plurality of RA resource sets includes RAR window information,
the RA procedure includes determining a RAR window for each resource of the plurality of resources corresponding to the selected RA resource set, and
the method further comprises monitoring for the plurality of RARs based on the determined RAR window for each resource of the plurality of resources corresponding to the selected RA resource set.
28 . (canceled)
29 . (canceled)