Beam training and initial access

1. An apparatus comprising:

a non-transitory memory including instructions stored thereon for beam link pairing the apparatus to a gNB in a new radio; and

a processor, operably coupled to the non-transitory memory, capable of executing the instructions of:

detecting synchronization signal (SS) blocks;

receiving physical random access channel (PRACH) resource information in master information block (MIB) on physical broadcast channel (PBCH) or system information block (SIB) on secondary PBCH (SPBCH), the PBCH indicating a location of the SPBCH, the SPBCH carrying system information indicating the PRACH resource information, the PRACH resource information being exclusively mapped for a group of the SS blocks, the SS blocks including a primary or secondary synchronous sequence and the PBCH;

transmitting PRACH preambles through a set of uplink transmission beams in a subframe including the group of SS blocks, the PRACH preambles being obtained from the PRACH resource information;

determining the apparatus is in a radio resource control (RRC) connected state;

participating, while in the RRC connected state, in beam training with the gNB via configured channel state information reference signals (CSI-RS); and

then participating in beam refinement with the gNB.

2. The apparatus of claim 1 , wherein the apparatus is further configured to:

monitor a physical downlink control channel (PDCCH) for a random access response (RAR) including a random access radio network temporary identifier (RA-RNTI); and

determine the RA-RNTI corresponds to the transmitted PRACH preambles.

3. The apparatus of claim 1 , wherein the PRACH preambles are obtained based on beam ID associated with the group of SS blocks.

4. The apparatus of claim 1 , wherein the SS blocks and the set of uplink transmission beams are separated by a gap.

5. The apparatus of claim 1 , wherein a set of PRACH resources mapped to the SS blocks correspond to a beam in a downlink for initial access.

6. The apparatus of claim 5 , wherein the PRACH resources are semi-statically configured by the gNB.

7. The apparatus of claim 1 , wherein the PRACH preambles include a preamble part and a message part.

8. The apparatus of claim 7 , wherein a beam ID is signaled in the message part.

9. The apparatus of claim 1 , wherein the PRACH preambles are swept through a set of potential uplink transmission beams.

10. The apparatus of claim 1 , wherein a random access resource (RAR) includes an uplink transmission beam ID feedback of the apparatus.

11. The apparatus of claim 1 , wherein the processor is further capable of:

receiving a multiple set of channel reference information reference signal (CSI-RS) configurations for the beam link pairing; and

transmitting a single beam report feedback according to the multiple set of CSI-RS configurations.

12. The apparatus of claim 1 , wherein the apparatus is a smartphone, wearable device, tablet or laptop.

13. An apparatus comprising:

a non-transitory memory including instructions stored thereon for beam link pairing the apparatus to a UE in a new radio; and

a processor, operably coupled to the non-transitory memory, capable of executing the instructions of:

transmitting physical random access channel (PRACH) resource information in master information block (MIB) on physical broadcast channel (PBCH) or system information block (SIB) on secondary PBCH (SPBCH), the PBCH indicating a location of the SPBCH, the SPBCH carrying system information indicating the PRACH resource information, the PRACH resource information being exclusively mapped for a group of synchronous signal (SS) blocks, the SS blocks including a primary or secondary synchronous sequence and the PBCH;

receiving PRACH preambles through a set of uplink transmission beams in a subframe including the group of SS blocks, the PRACH preambles being obtained from the PRACH resource information;

determining the UE is in a radio resource control (RRC) connected state;

participating in beam training with the UE being in the RRC connected state via configured channel state information reference signals (CSI-RS); and

then participating in beam refinement with the UE being in the RRC connected state.

14. A wireless communication method for beam link pairing with a UE, the wireless communication method comprising:

transmitting physical random access channel (PRACH) resource information in master information block (MIB) on physical broadcast channel (PBCH) or system information block (SIB) on secondary PBCH (SPBCH), the PBCH indicating a location of the SPBCH, the SPBCH carrying system information indicating the PRACH resource information, the PRACH resource information being exclusively mapped for a group of synchronous signal (SS) blocks, the SS blocks including a primary or secondary synchronous sequence and the PBCH;

receiving PRACH preambles through a set of uplink transmission beams in a subframe including the group of SS blocks, the PRACH preambles being obtained from the PRACH resource information;

determining the UE is in a radio resource control (RRC) connected state;

participating in beam training with the UE being in the RRC connected state via configured channel state information reference signals (CSI-RS); and

then participating in beam refinement with the UE being in the RRC connected state.